Cooling system idiosyncrasies 2006

c:\sporlan 2006\cooling idiosyncrasies

by

Garth Denison

Sr. Product Application EngineerSporlan Valve DivisionParker Hannifin Canada

2006 / 2007 SeminarCooling Systems

" Idiosyncrasies "

There is humor in those

Cooling Idiosyncrasies.


" Cooling Systems Idiosyncrasies "

A behavioral characteristic unique to an individual or group

The Sporlan Valve Division, Parker Hannifin assumes no obligations or liability for any advice furnished or for any results, property damage or personal injury including death that may result with respect to the use of this information. All such advice is given and accepted at users risk. This disclosure of information herein is not a license to operate under, or a recommendation to infringe any patent of Sporlan Division of Parker Hannifin or others.

® Registered trademark of Sporlan Valve Division, Parker Hannifin Corporation, Cleveland Ohio USA© Copyright 2005 by Sporlan Valve Division, Parker Hannifin Inc


Service Guide to Various

System Idiosyncrasies

Bull HeadingSplit Condensers

above 50°F

below 50°F


35 40 45 50 55 60 65 70 75 80 85 90 95 100 105 110 115 120

DRY BULB TEMPERATURE - °F

10 15 20 25

30

35

40

45

50

55

55

60

60

EN

THA

LPY

-BTU

PER

PO

UN

D O

F D

RY

AIR

ENTHALPY - BTU PER POUND OF DRY AIR

15

20

25

30

35

40

45

50

ENTHALPY - B

TU PER P

OUND OF D

RY AIR

SATURATION TE

MPERATURE - °F

.002

.004

.006

.008

.010

.012

.014

.016

.018

.020

.022

.024

.026

.028

35

3540

40 45

45 50

50 55

55 60

6065

6570

70

75

75

80

80

85 WET BULB TEMPERATURE - °F

85

90

10% RELATIVE HUMIDITY

20%

30%

40%

50%

60%

70%

80%

90%

12.5

13.0

13.5

14.0 VOLU

ME - CU

.FT. PER LB. DRY AIR

14.5

15.0

HU

MID

ITY

RAT

IO -

POU

ND

S M

OIS

TUR

E P

ER

PO

UN

D D

RY

AIR

.05

.1

.15

.2

.25

.3

.35

.4

.45

.5

.55

.6

.65

.7

.75

.8

.85

.9

.95

1

1.05

1.1

1.15

1.2

1.25

1.3

1.35

VA

POuR

PR

ES

SU

RE

-IN

CH

ES

OF

ME

RC

UR

Y

010

2025

30

35

40

45

50

55

60

65

70

75

80

85

DEW

PO

INT

TEM

PER

ATU

RE

-°F

1.000.95

0.90

0.85

0.80

0.75

0.70

0.65

0.60

0.55

0.50

0.45

0.40

0.350.300.250.200.15SENSIBLE HEAT RATIO = Qs / Qt

SE

NS

IBLE

HE

AT R

ATIO

= Q

s / Q

t

R-410A

CT 162 °F, CP 715 psia

Note importance ofsub-cooling

Bull Heading

above 50°F

Split

Con

dens

ers

below 50°FAB

POE

MO


For 2006


Refrigerant Science of Yester Year

Temp / Press psigName Formula Flammable 0°F and 85°F

F-12 CCl2F2 No 9.2 91.7

Sulphur Dioxide SO2 No 8.9” 50.6

Ammonia NH3 Yes (16 to 25) 15.7 151.7

Butane C4H10 Yes (1.6 to 6.5) 15.0” 26.2

Iso Butane C4H10 Yes (1.8 to 8.5) 6.3” 43.9

Carbon Dioxide CO2 No 293.9 1012.3

Methyl Chloride CH3Cl Yes (8.1 to 17.2) 4.1 79.4

Ethyl Chloride C2H5Cl Yes (3.7 to 12) 21.6” 11.9

Methylene Chloride CH2Cl2 Yes (8.1 to 17.2) 27.9” 9.9”

Dichlorotetrafluoroethane C2Cl2F4 No 17.8” 21.0

Source: Frigidaire engineering manual Nov. 15, 1938


Global Warming … Kyoto


" Typical Receiver Types "


Receivers

For receivers having an internal diameter of 6 inches (150 mm) or smaller: ARI 495, UL listed, steel, brazed, 400 psig (2760 kPa) pressure rating, with pipe threaded female access fittings for inlet, outlet, and pressure relief valve.

Receivers larger than 6 inches (150 mm) diameter: ARI 495, welded steel,tested and stamped according to ASME Boiler and Pressure Vessel Code:Section VIII; 400 psig (2760 kPa) pressure rating, with pipe threaded femaleaccess fittings for inlet, outlet, pressure relief valves, and a liquid level indicator.

Typical receiver accessories ..

Relief device (valve or fusible plug)

Dual relief valve saddle assemblyLiquid level indicator / alarmSight glassReceiver heaterInsulated receiverAccess / Isolation valves


Typical Receiver Types

From condenser To evaporator

Receiver

indicates vapour

indicates liquid

Minimum refrigerant charge is 15% of receiverscapacity to ensure a liquid seal at the dip tube.

Liquid Line

Surge Receiver

No minimum receiver refrigerant charge needed

Receiver styles:vertical

horizontal

Vent line


System with Receiver

The circled area represents a typical receiver installed in the liquid condensate line.

Receiver may or may not effect the quantity of sub-cooling depending onrefrigerant’s speed, receivers ambient and system’s refrigerative effect.


System with Surge Receiver

The circled area represents a typical surge receiver installed in the liquid line.

A surge receiver will not effect the quantity of sub-cooling. Refrigerantnot required to accommodate the load will back into the surge receiver.


Receiver Components & Accessories

Level indicators / Alarm actuators

Typical relief valve

Dual relief valve assembly

Pressure transducer,gauge and relief valve

Straight-thrurelief valve

Poly Tetra FluoroEthylene (Teflon)

&Fusible plugs


R.V.Setting

Tolerance

+ 10 % R.V. Full Open

Maximum system operating pressure

Relief Valve (R.V.) Setting

- 10 % Potential R.V. “Seep” Point

Relief Valve Parameters

Relief valve parameters as a percent of R.V. set pressure.

PSI

440

400

360

320

Suction header

High PressureReceiver

Reliefvalves

Added protection is a High / Low By-pass valve if system pressure nears thepotential relief valve “Seep” Point.

Source: Henry Technologies

A typical installation with a pressure vessel havinga maximum working pressure of 400 PSI might be:

Relief Valves 400 PSI: Set at the design working pressure of the vessel OR25 % higher than the maximum working pressure of the system.

High / Low: Set at approximately 80 – 85% of relief valve setting. 330 PSI

Relief Valve: Table below for code parameters for a400 PSI relief valve. IN

OUT

High / LowBypass valve


Receiver Components & Accessories

Synthetic ester oil based greaseusing a lithium soap.

SKF system grease LGLT-2

Operating temperature range

-55ºC to 110ºC

-65ºF to 230ºF

Indoors Outdoors


Receiver Heaters

Various Heater TypesStrap-on heaterInsertion heaterEmersion heaterPeel & Stick foil backedMagnetic heater stripsBlanket heater


" Reversing Fuses "

For testing purposes ONLY …How can a technician change rotationon a three phase application without

moving a wire ?

Thought Provoking !!!


Reversing Fuses

EXTREME CAUTION

Uninstalled Fuses

Blo

wn

/ Bad

Fus

e

Blo

wn

/ Bad

Fus

e

Heavy Wire

Heavy Wire

Fuse

Fuse


Reversing Fuses

EXTREME CAUTION

Installed Fuses

Blo

wn

/ Bad

Fus

eB

lown / B

ad FuseHeavy WireFuse

Fuse


" Receivers and their Affects "


Air Cooled Condenser Typical Split Condenserc/w Standard Receiver

Liquid lines

Summer

ORI / OROA

Restrictor tube tolow side may beused to controlpump out rate ofinactive condenser

To evaporator

Receiver

R-22 condenser converted to R-404A,approximately a 10% gain in capacity.

Minimum refrigerant charge is 15% of receiverscapacity to ensure a liquid seal at the dip tube.


Air Cooled Condenser

Liquid lines

Summer

ORI / OROA


8, 12 or 16D

To evaporator

Receiver

Typical Split Condenserc/w By-pass Receiver


Shown de-energized


Three Way Solenoid

From condenser

To receiver

To liquid line De-energized

Energized

1. High pressure refrigerant 2. Piston vent line3. Open to low pressure

8D, 12D, 16D


De-energized


Energized



Liquid lines

Summer

ORI / OROA


Liquid Line

Surge Receiver

No minimum receiver refrigerant charge needed

Typical Split Condenserc/w Surge Receiver


Vent to condenser inlet,check valve installed

in this line.

“weir”

receiverinlet / outlet


Why Typical Split Condenser Vertical Drop ?


Split Condenser Circuits

Liquid lines

ORIT / OROA


** Note: ARI check valve acceptable leak rate is 750 ml/minuteone US gal = 3.8 liters (1 liter = 1000 ml)

** Typical 6 ft.

Density Specific. 1 psiRef. lb/ft3 Gravity Lift in ft.

R-22 74.5 1.20 1.93R-134a 75.1 1.21 1.91R-404A 65.5 1.05 2.20R-407C 70.8 1.14 2.03R-507A 65.5 1.05 2.20

R-410A 67.7 1.09 2.12

R-12 81.8 1.31 1.76R-502 76.0 1.22 1.89R-718 62.3 1.00 2.31

Specific Gravity = Density / 62.311 psi Lift in ft. = 2.31 / SG

Densities are at 25ºC or 77ºF

23.222.926.424.426.4

25.5

21.122.127.7

Lift ininches


" Multi Receivers and their Affects "


Variances in Lift Verses Density .. @ 1 psi

one psi

Typical refrigerant1.8 feet or 21.6 inches

Refrigerants

Water H2O2.31 feet or 27.7 inches

Water

one psi

Typical lubricant2.5 feet or 30 inches

Lubricants

one psi

Refrigerant R-7173.9 feet or 47 inches

Ammonia

one psi


Series ReceiversWater cooled condensersInsufficient existing capacity

Normally 2 or 3 in series

Multi Receivers

Parallel ReceiversDifficult in controlling liquid levels

Possible liquid in one and vapour in other


When Supplemental Receiversare Needed

Auxiliary receivers may be necessary when refrigerant pumpdown capacity is less than the proper operational charge of refrigerant in the system. This condition sometimes occurs inwater cooled systems where the condenser-receivers have limited capacity and it can alsooccur in any system where large evaporators or long liquid lines are used or where the pumpdown liquid solenoid valves cannot be located close to the TEV’s. To correct this condition, an additional receiver with the necessary holding capacity should be installed in series with and close to the outlet of the main receiver on the compression unit.

The auxiliary receiver should be installed on the same level or below the main receiver on thecompression unit. Both the main and auxiliary receiver must have their own service valves,fusible plug or relief valve. The liquid line sightglass, drier and the liquid line to the evaporatorshould then be connected in the normal manner to the service valve which is installed on theoutlet fitting of the auxiliary receiver.


Supplemental Receivers

" Series " Receivers

Main

Auxiliary

Receiver

Catch-All

See-All

Solenoid

Catch-All

See-All

Solenoid


Typical Copeland " C " Line Condensing Units

Liquid InOutletValve

Cross sectional view of two refrigerant receivers in series

one psi

Typical refrigerant2.0 feet or 24 inches

Refrigerants


" Effects of Sub-cooling "

An Idea Whose Time Has Come


Sub-cooling

The reduction of the liquid refrigerant’s temperatureto a point below its saturation temperature.

Sub-cooling is always the removal of sensible heatonly from a liquid phase fluid.

Definition:

Up to 20% increase in Btu loadingDecrease in electrical usage as much as 25%Reducing pull-down time up to 50%Provide more uniform refrigerating temperaturesReduces first cost, by permitting down sizing ofcompressors in new system.

Obtainable:


Understanding Heat in the five Regionsof a Ph Diagram

Sensible heatregions

Latent heatregion

Satu

rated

liqui

d lin

e …

Bubbl

e Poin

t

Satu

rate

d va

pour

line

…D

ew P

oint

SuperheatedVapour region

SubcooledLiquid region

" Quality "(% vapour)

Liquid / Vapourmixture region

0.1 0.2 0.3

0.4 0.5 0.6

0.7

0.8

0.9

Solid region Triple point

Critical PointGaseous region


Consider the Following:

The compressor is a fixed displacement pump. It is pumping a certain number of CFM (pounds) of refrigerant through thecycle, and really doesn’t care how many Btu’s are in each oneof those pounds. So by increasing the number of Btu’s perpound, we can increase the capacity of the system while notincreasing the mass flow of refrigerant.

Increasing Sub-cooling Reduces Flash Gas,Increases Net Refrigeration Effect.


Sub-cooling can:

1. Increase capacity2. Decrease electrical usage3. Reduce equipment maintenance4. Produce better temperature control5. Reduce pull-down time after defrost6. Reduce first costs


What do the headlights on a motor car and on a bus have to do with you, the

refrigeration and air conditioningtechnician ?



MC and B tanks

40 cu ft

" B " Bus10 cu ft

" MC " Motor Car

(acetylene)

MCB

Acetylene HeadlightsHenry Ford Museum, Dearborn Michigan


" Accomplishing Sub-cooling "


Types of Sub-cooler

Ambient sub-coolingAirWaterRefrigerant

Mechanical sub-coolingIntegral part of systemSelf contained refrigeration systemUsually brazed plate heat exchangers

Both styles actually refrigerate the refrigerant.


PREFERRED

ACCEPTABLE

NEVER

Installation & Mounting ...

For Single Phase, Liquid-to-Liquid Applications


Installation & Mounting ...Effect of Inclination on Two Phase, Refrigerant Applications

55

3030

45

45 60

60

90

90

0

-3%-2%-10%

-16%

-38%

-9%

-15%

-37%

Evaporator -No measurable difference

within ± 5º of vertical.

Based on testing conducted by NIST. R-22 evaporator.


Installation & Mounting ...Effect of Inclination on Two Phase, Refrigerant Applications

55

3030

45

45 60

60

90

90

0Condenser -

No measurable difference.

Short term limited test.

Based on testing conducted by NIST. R-22 evaporator.


Typical Plate to Plate Heat Exchangers,Sub-coolers

Sub-coolers

The brazed plate heat exchanger is substantiallysmall than other technologiesthat could be used.

The EPR valve should normally be set to maintaindesired liquid temperature. This is normally 50°F

but may be as low as 40°F for some systems.

Mechanical sub-coolers leavingliquid refrigerant temperature isusually controlled by a temperaturesensor on the condensers liquidcondensate drop leg.


Refrigeration Retrofitting R-22 to R-404A

Regaining the Lost Capacity

from receiver

toliquid manifold

TEV’s

tosuction manifold

EPR

solenoids

Plate to PlateHeat exchanger

Plate to PlateHeat Exchanger


Specific Heat .. the amount of heat needed to raise / lower onepound of a substance one F°. (Btu/lb. F° sensible heat)

Thermodynamic 411

R-22

R-404A

Btu/lb F°Cp 0.300

Cp 0.367

R-407C

R-410A

Btu/lb F°Cp 0.368

Cp 0.440

Refrigerant Liquids

Source DuPont AG3 and AG2


Sub-cooling Calculation Example

R-22 has a Specific heat (Cp ) of 0.300

Example:

Liquid refrigerant entering sub-cooler is 100ºF

Desired refrigerant temperature leaving sub-cooler 50ºF

Formula used is Mass x Specific heat (Cp) x Delta temperature

Refrigeration effected needed per pound of mass flow is 1 x 0.300 x 50 = 15 btu’s

A system having a mass flow rate of 13 pounds per minute needs 13 x 15 = 195 btu’s or 1 ton

Using the same conditions:360,000 btu’s (30 ton LT) rack would need approximately 105 lbs/min

Sub-cooling capacity 105 x 0.300 x 50 = 1575 btu’s or 1575 / 200 = 7.9 tons

TEV’s for Sub-cooler .... One three tons and one five ton


Plate to Plate Heat Exchanger

from receiver

toliquid manifold

TEV’s

tosuction manifold

EPR

solenoids

Mechanical Sub-cooler

The brazed plate heat exchanger is substantially smaller thanother technologies that could be used as a liquid sub-cooler.Typically the rack controller has a temperature sensorthat will sense the refrigerant drop leg (condenser return)line to the receiver. Depending on the refrigerant type andsystem design it is quite normal to supply 40 to 50 °Fsub-cooled liquid refrigerant throughout the network.

An example of a typical Sub-coolers operation is as follows:no solenoids energized = no additional sub-cooling# 1 solenoid energized = 3 additional tons# 2 solenoid energized = 5 additional tons# 1 and # 2 solenoids energized = 8 additional tons

The EPR is normally set to maintain the minimum desiredliquid refrigerant supply temperature. This is normally50°F but may be as low as 40°F for some systems. A sub-cooler EPR settings of 68 psig will have a SST of 40°F for R-22 and 29°F for R-404A.

The liquid line solenoids in front of the sub-cooler expansion valves close when the condensers drop leg temperature gets below the set point thereby shutting off the sub-cooler.

Plate to PlateHeat exchanger


How Sub Cooling Affects System Capacity

R-22

For every 10F° of sub coolingof R-22 will equal a 6% reduction in refrigerant mass flow requirements.

Example: SCT 100 FSST – 25 FSC 0FSH 25 FLOAD 5TBTU/LB 62.6

SCT 100 FSST – 25 FSC 50FSH 25 FLOAD 5TBTU/LB 77.6

Summary:

77.6 / 62.6 = 1.24Therefore 2F° SC = 1 % capacity increaseRefrigerant circulated 15.9 to 12.9 lb/minCompressor displacement from 44.1 to 35.5 cfm

R-404A / R-507

For every 10F° of sub coolingof R-404A / R-507 will equala 10% reduction in refrigerantmass flow requirements.



Example:

Summary:

58.4 / 38.6 = 1.51Therefore 1F° SC = 1 % capacity increaseRefrigerant circulated 25.9 to 17.2 lb/minCompressor displacement from 49.7 to 32.9 cfm

NOTE: the above outlined calculation were determined by the use of DuPrex computer program


What is the controlling capacityfactor of any refrigeration

system ?

The choke point …." Evaporator "



" Economizers when Multi Staging "


Open Economizer

refrigerant vapour to compressor’s inter-stage

liquid refrigerantto

Evaporator (s)liquid refrigerantfrom condenser

saturated refrigerantat inter-stage pressure

spraynozzles

open economizer

indicates vapour

indicates liquid

The " Open or Flash " economizer is simply a tank, which is vented to the compressors inter-stage.The refrigerant flashes, evaporating some of the refrigerant, cooling the remaining liquid to the saturation temperature corresponding to the inlet pressure of the compressor inter-stage. The open or flash economizer is an economical, efficient method of cooling liquid refrigerant en-route to the evaporator (s). Open economizers are generally used when high efficiency is requiredas they also reduce the BHP requirements.


2nd stage

1st stage

Open Economizer

" Open or Flash " economizer


closed economizer

refrigerant vapour to compressors inter-stage

Sub-cooled liquidrefrigerant to

evaporator (s)

liquid refrigerantfrom condenser

levelcontroller

indicates vapour

indicates liquid

liquidrefrigerant

Closed Economizer

The " Closed " economizer takes the liquid from the condenser and splits the flow into two streams.Most of the refrigerant flow goes through the tubes of a shell and tube heat exchanger; the remainingrefrigerant goes to the shell side through a control valve to be boiled off to cool the refrigerant in thetubes. The vapour generated is vented to the inlet of the compressors inter-stage.


Closed Economizer

2nd stage

1st stage

" Closed " economizer


Two Stage A/C Cooling !!

His and Hers ??


Summary

Up to 20% increase in Btu loadingDecrease in electrical usage as much as 25%Reducing pull-down time up to 50%Provide more uniform refrigerating temperaturesReduces first cost, by permitting down sizing ofcompressors in new system.

Catch-All

See-All

Solenoid

Possible reselection of TEVand distributor orifice disc needed


Affects of Sub-coolingon TEV’s Capacity

Refrigerant 100°F 60°F 50°F 40°F(0°SC) (40°SC) (50°SC) (60°SC)

R-134a 100% 1.29 1.36 1.42R-401A 100% 1.25 1.31 1.36R-409A 100% 1.23 1.28 1.34

R-404A 100% 1.43 1.54 1.64R-408A 100% 1.27 1.34 1.40R-507 100% 1.40 1.50 1.59

R-22 100% 1.23 1.29 1.34R-407C 100% 1.28 1.35 1.42


" Accumulators and their Affects "


Hold approximately 50% of systems charge in TEV systems

Hold approximately 70% of systems charge in fixed orifice systems

Standard screen in 3 inchdiameter accumulators

Standard screen in 3 through 6 inchdiameter accumulators

Metering orifice for oil return to the compressor located behind screen0.055” diameter for 3 through 5 inch diameter accumulators

0.080” diameter for 6 inch diameter accumulators

Accumulator Design


Original R-22 Screen

60 x 60 mesh of surface area

Smaller mesh can trap POE oils and

additives.

Mesh .. Number of openings per linear inch, measured from the centre of one wire to a point one inch distant.

Accumulator Screens

Mesh 0.001’s Microns

10 = 0.0580 = 150030 = 0.0194 = 50060 = 0.0097 = 250

100 = 0.0058 = 150 140 = 0.0041 = 105200 = 0.0029 = 74350 = 0.0017 = 44

Increased surface area retains more contaminants without plugging.

30 x 30 mesh screen prevents POE oils & additives from becoming trapped due to surface tension .

Enhanced HFC Screen


Odor eaters ..

Odors … Bacteria

CharcoalBaking Soda

FDS (feminine deodorant spray)

foam core insulation, not fiberglass


Personal level ..Vicks Vapor Rub … your upper lipBasil … nasal snort


Effects of Hydrostatic Pressures ?

Lets Look at it.


Temperature °F

Pres

sure

ps

ig

200

600

1000

1400

1800

2200

2600

40 60 80 100 120 140 160 180

Typical Effects of Hydrostatic Pressure

Hydrostatic PressureIncrease

R-12/R-134a is 40 psi / each F°R-22 is 60 psi / each F°

R-410A is 45 psi / each Fº

4BA / 4BWBurst Pressure

1040thru1600

R-2240°F is 70 psi

180°F is 540 psi

R-12/R-134a40°F is 37 psi

180°F is 330 psi

R-410AR-22

R-12 & R-134a

ReliefDevices390 psi

thru800 psi

R-410A40°F is 120 psi155°F is 645 psi

3200

Receiver to Solenoid ?


Liquid line solenoid100 feet away.

System:

R-22, with MO- 25ºF SSTElectric defrostPump out systemLP control cutout1 psig (- 40ºF)

Freezer at- 17ºF

Freezer at- 17ºF

Freezer at- 17ºF

Troubled System … 6 TEV’s ReplacedStill High Super Heat ?

“Tee”

Found a 30Fº ∆ across Tee


Blood Storage RoomProblem: loss of critical temperaturecontrol, in a continuous operation.

Picture is of Hot Gas stabilizer line atevaporator inlet, solenoid 8 ft aboveoutside box in a 74ºF ambient.

Blood Storage Roomcritical application

- 30ºC or - 22ºF


Modern ServiceTechnician

Fouling !!!!!


A 0.042" Film of Dirt on a Coil

Equals 21% Loss in

Heat Transfer Efficiency


" Servicing a Winter Charge"


SporlanBulletin90-30-1


Sporlan Bulletin 90-30-1

Refrigerants listedR-12 R-22 R-134a R-401A R-401BR-402A R-402B R-404A R-407C R-408AR-409A R-502 R-507


SporlanBulletin90-30-1


Sporlan Bulletin 90-30-1


Servicing a Winter Charge !!!

To calculate the correct additional winter operationalrefrigerant charge needed at winter design follow

the procedure as outlined in Sporlanbulletin 90-30-1 dated July 1998.

How to calculate the needed additional refrigerant if only a partial charge exists.

1. Calculate the correct added winter refrigerant charge for the winter design conditions. eg: 128 lbs @ - 20ºF. (follow procedure as outlined in Sporlan bulletin 90-30-1 dated July 1998)

2. Take and record the current outdoor ambient air temperature. eg: + 20ºF3. Add refrigerant until the sight glass just clears and record the quantity of refrigerant added. eg: 17 lbs4. Recalculate the added winter charge for the current existing ambient temperature. eg: 98 lbs @ + 20ºF.

(this unit now contains the correct operational winter charge for its current ambient air temperature)5. Additional refrigerant needed to operate at – 20ºF is 128 – 98 = 30 lbs.6. In this example the billable refrigerant charge would be 17 + 30 or 47 lbs.


Fin and Tube Heat Exchangers

Used for both evaporatorsand condensers.

TUBESPrimary Surface, usuallymade of copper (Cu).

FINSSecondary

Surface,usually madeof Aluminum

(Al)


Coefficient of Expansion

Coefficient of Expansion

Cu is 0.0000104 of an inch / per inch / per F°

or

1.04E-5 per inch / per F°

Al is 0.0000130 of an inch / per inch / per F°

or

1.30E-5 per inch / per F°

Source: American Machinists Handbook, p 33 - 29


2 Lines of Nozzles


“Aluminum will creep and move approximately 33% morethan copper. This large movement will eventually lead tofatigue failure.”

“Through repetitive thermal cycling, aluminum laminations(fins) can become loose, resulting in early failure.”

Cu vs Al

Source: elettra technology inc.

H2O (hard or soft) will evaporate AND cause residue (residual) deposits of either or both mineral and / or oxides to be left behind. This residuewill be deposited on or between the Cu and Al thereby increasing theheat exchanger’s fouling factor. This increase interferes with the heat transfer process causing a loss of efficiency and capacity.


Other Considerations

• Continues running of water .. Added costswater cost / sewer charge

• Roof will not dry off … permanent roof damage

• Loss of head pressure control as temperature changes

• Environmental aspects

• Outdoor installation, freezing prospects

• Repeated calls to start / stop adjust etc:

• Equipment life shortened, rust, motors, belts, drives


And Then There is theOther Contractor



Poor Bulb Location = Floodback

Show smashed compressor parts …………….


Built-in Redundancy !!!


10 Units in 48” wide passage !!!


Location .. Location .. Location

First Rule in Real Estate


Residential Split Systems

Traditional / StandardMethod

Typical Cool ClimateInstallation ?


Residential Split Systems

Second Alternative, Knee Braces on outside wall.Pro’s: Not effected by ground thermo shear.

Landscaping not completed .. RNC market.Con’s: Sound transmission, harmonics through wall.

Isolation pads may be needed ?

Secure top of hairpin only .. Allows opening / closing

Preferred InstallationMethod


Didn’t like the look …Must hide the Condensing unit


R-410A ? Under the Deck …unit will die of emphysema !!!

RedRock Clubhouse, prestigious golf course inSouth Carolina. Removed 4” of pine needles toget units in and then only 1” top clearance onsecond unit.


Typical Ductless Split Installation


Then There is the Contractor ABC( Always Bring Cash )


Cross supports ????

Safe

ty …

!!!!!!

Chicken crates

Entranced way


Home on pillars, note condensers discharge ducton top of unit, complete with turning vane.

Attic installation in a SouthernState. Do it yourself installationdream.


Access Ladder to Roof


Three Compressors !!!


FIDO


38HQ three piece heat pump, Low ceiling re-circulated air.Note: longer piping run but proper location of fittings for oil return.

Installation is everything ?Location Location Location

c:\sporlan 2006\cooling idiosyncrasiesGate Valves ????

The Plumber !!!


Nylon Tie Wraps !!!!


Controlling Lubricantsand Discharge Temperature


Typical Refractometer


Refractometer Readings

Approved OEM POE Lubricants:

Copeland, all reciprocating and scroll refrigerationEmkarate … RL32CF .. 1.4546

Carlyle / Carrier all O6D & O6EEmkarate … RL68H … 1.4557

Carlyle / Carrier all O5T & O6T screwsEmkarate … RL100S .. 1.4574

Mineral Oils .. 3GS: 1.4942, 4GS: 1.4973, 5GS: 1.4953

Alkylbenzene … 150: 1.4865, 200TD: 1.4859, 300: 1.4844

Source Nu-Calgon 3-240

(150 / 32) (500 / 100)(300 / 68)Viscosities SUS / ISO


Polyolester Lubricants

RL22H RL22N RL32CF RL32S RL32H RL68H RL68HP RL68S RL100S RL150S RL220H1.4519 1.4521 1.4546 1.4546 1.4530 1.4557 1.4557 1.4564 1.4574 1.4581 1.4580

Emkarate OEM approved lubricants

Bitzer Recp. X XScrew

Bock X X X Bristol XCarlyle Recp. X

Screw XCopeland XD/Bush Recp. X X

Screw X Embraco XGrasso XManeurope XMatsushita XPrestcold XRoyce X XSabroe X X X X X X X Sea Container X SRM X Tecumseh XThermoking XTrane* Screw X

Scroll XYork* Recp. X

Screw X

McQ

uay

R-1

34a

cent

rifug

als m

odel

s 05

0, 0

63,

079,

087

Car

rier R

-134

a ce

ntrif

ugal

s mod

els

19X

T, 1

9XR

, 19

XR

T, 1

9EX

Emkarate lubricantRefractive index

source: Nu-Calgon 3-68 + Carrier

Suffixes:CF = Copeland formulationH = High solubilityS = Standard solubilityN = Special for McQuayHP = Special for Carrier

by Garth Denison

* Trane and York low pressure centrifugals use OEM approved mineral lubricants.

Bitzer ScrewEmkarate RL170H

1.4576BVA Solest 170

1.4558


Cross Lubricant Contamination

POE

ABMO

AB … Alkylbenzene OilMO … Mineral OilPOE … Polyol ester Oil

< 50 %

< 5 % < 5

%

Note:

Lubricants are 100% misciblewith each other. Their degree

of miscibility with variousrefrigerants varies from

0% to 100%.

Generally Accepted Lubricants

CFC’s and HCFC’s use MO or ABHFC’s and PFC’s use POE


0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 1001.440

1.445

1.450

1.455

1.460

1.465

1.470

1.475

1.480

1.485

1.490

1.495

1.500

Refractometer GraphRefractive Index vs Residual Oil Content

Residual (%, wt) of Old Oil


Note: Always take readings after " De-gassing " lubricant

1.51

1.50

1.49

1.48

1.47

1.46

1.45

1.44

1.52

1.51

1.50

1.49

1.48

1.47

1.46

1.45

1.44

1.52

RefractiveIndex

nD

Scale

Refractometer Eye Piece

nD = reactive Divergence


0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 1001.440

1.445

1.450

1.455

1.460

1.465

1.470

1.475

1.480

1.485

1.490

1.495

1.500

MO3C / 3GS – 1.49424C / 4GS – 1.49735C / 5GS – 1.4953

AB150 – 1.4856

200TD – 1.4859300 – 1.4844

POECopeland – 1.4546

Carlyle O6D/E – 1.4557Carlyle O5/6T – 1.4574



POE1.4557

MO1.4942

Sample lubricant example,a reading 1.474 would

represent 44% POElubricant.


POE

0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 1001.440

1.445

1.450

1.455

1.460

1.465

1.470

1.475

1.480

1.485

1.490

1.495

1.500

MO

AB

MO3C / 3GS – 1.49424C / 4GS – 1.49735C / 5GS – 1.4953

AB150 – 1.4856

200TD – 1.4859300 – 1.4844

POECopeland – 1.4546

Carlyle O6D/E – 1.4557Carlyle O5/6T – 1.4574 Source: Nu-Calgon # 3 – 242

Maximum cross lubricant contamination with POE’s is 5%



Acceptablerange1.4546

to1.4595


Desired refractive range is between

1.4546 to 1.4595

This will ensure less than

5% cross lubricant

Refractometer Graph

Refractometer Sources:

1. ATAGO P/N N-30002. Copeland P/N 998-RMET-00


Service Refractometer

1.4546 to 1.4595


Temperature ResponsiveExpansion Valve (TREV)

Typical U.S. Green Compressors

OEM Discharge head sensor:

Refrigeration dutyopens 325°F +/- 8closes 250°F +/- 12

Air Conditioning dutyopens 295°F +/- 5closes 235 minimum

Typical Black Compressors

eg: OEM Demand Cooling™

Injects refrigerant at 292°FShuts refrigerant off at 282°F

If compressor operates at310°F for 60 seconds thecontroller will shut the unitoff on safety.

Y 1037


Lubricant Functions

Other Functions: …1. Makes a fluid seal .. prevents blow by

2. Acts as a coolant .. compressor and hermetic motor

3. Dampens mechanical noise .. POE’s 1½ louder, dB scale

4. Provides electrical insulation .. hermetic systems (25Kv)

Purpose: … to minimize friction and prevent wear of moving parts.

Tribology: .. the study of interacting surfaces in relative motion and associatedissues, such as friction, lubrication and wear. (friction and wear)


Additional Piping Considerations

Refrigerant goes to Lubricant

Lubricant DOES NOT go to Refrigerant

Refrigerant is soluble (dissolved) in lubricant .. similar to sugar in coffee (one liquid phase) until CST (Critical Solution Temperature)

is reached then there is two liquid phases (one refrigerant + one lubricant).

Note: OEM’s of ductless splits recommend NO traps.


Lubricant movement within a typical system

Properly designed refrigeration / air conditioning system3 to 5% of compressor’s lubricant is in circulation at all times.MO / AB is approximately 30% miscible with their typical refrigerant’s, the remaining lubricant travels by peristalsis, this is caused by the refrigerant’s velocity.

POE lubricants with HCFC or HFC refrigerants are 100% misciblebetween from + 176° F (+ 80° C) through – 76° F (- 60° C), thereforethe circulating lubricant travels in suspension.

Miscibility … the ability to mixSolubility … the ability to dissolveCST … Critical Solution TemperatureLubricants are miscible with other lubricantsLubricants are miscible at different percentages in refrigerantMoisture (H2O) is soluble in POE lubricant


Variances in Lift Verses Density .. @ 1 psi

one psi

Typical refrigerant2 feet or 24 inches

Refrigerants

Water H2O2.31 feet or 27.7 inches

Water

one psi

Typical lubricant2.5 feet or 30 inches

Lubricants

one psi

Refrigerant R-7173.9 feet or 47 inches

Ammonia

one psi


“RISER”45° Street El

45° Street El

90° Short Radius El

Oil Trap Construction


The oil drains from the riser & sloped horizontal piping to fill the trap

Oil Trap During the Off Cycle


If a large surge of vapour enters the trap

The oil could be forced out of the trap as a slug

For this reason the oil holding volume of the

trap is kept to a MINIMUM

Oil Trap at Start Up


Which trap is more likely to kill a compressor with

an oil slug?

Oil Traps Compared


Usually, the amount of vapour entering the trap gradually increases

The oil is then pushed through the trap until a gap is formed here

Because the gap has a small area,

the vapour passes through at high

velocity

The high velocity vapour carries oil droplets up the riser

Oil Trap at Start Up


Downward direction of flow & Horizontal line size is increased so

pressure drop is kept in an acceptable range

Riser line size is

reduced to maintain vapour velocity and oil

return up the riser

Reduced Size Riser


smaller RISER

“A”

larger RISER

“B”

The large volume of

vapour flow is split between

risers

Each riser has enough flow & velocity to carry

oil up the pipe

Double Riserat Full Capacity


smallerRISER

“A”

largerRISER

“B”

The small volume of vapour flow is not enough to carry oil

up both risers

The oil can’t be carried up the risers and fills

the trap

This blocks vapour flow in

Riser “B”

Then all the small volume of

flow shifts to Riser “A” with

enough velocity to carry oil up

the pipe

Double Riserat Low Capacity


Lubricant Miscibility SummaryCFC’s

w / Mineral oil-76F 2 phases +164F 2 phases +176F

w / Alkylbenzene -76F 2 phases -17F 1 phase +176F

HCFC’sw / Mineral oil -58F 2 phases +149F 2 phases +162F

w / Alkylbenzene -58F 2 phases +151F 1 phase +162F

w / Polyol ester-58F 1 phase +162F

w / Mineral oil-76F 2 phases +126F 2 phases +176F

w / Alkylbenzene-76F 2 phases +135F 2 phases +176F

w / Polyol ester -76F or -60C 1 phase +176F or +80C

Source: DuPont HP P.U.S.H.

HFC’s


Influence of Mineral Lubricant Filmon Heat Transfer

Source: Technicold Services Inc, George Briley P.E.

A film of only 1.5 mils of oil drops the heat transfer coefficient14% and a film of 3 mils dropsthe heat transfer by 25%. As the surfaces continue to “foul”, thesystem efficiency decreasesaccordingly.

Note: 1.0 mil = 0.001 inchAverage copper BTU/Hr/SF/Fº is 85 to 100


Lubricant is required to lubricate the moving parts within the compressor.Unfortunately lubricant and refrigerant have an affinity to each other and lubricant is constantly being depleted from the compressor sump and circulating about the piping system. Lubricant can get logged up in parts of the piping system and note return to the compressor sump. The rate of lubricant depletion must be equaled by the rate of lubricant being returned otherwise it is only a matter of time until the compressor is destroyed from lack of lubrication. Piping systems are designed as a trade off between pressure drop (system efficiency) and velocity (lubricant return). In other words larger pipes have less pressure drop which is good for system efficiency and smaller pipes cause higher velocities which improve lubricantmovement and the return of lubricant to where it belongs. Another problem with lubricant getting out is the piping system is that it acts as an insulator reducing heat transfer in coils. Oil separators capture most of the lubricant as it leaves the compressor and return it back to the compressor sump whereit belongs. There are three types of oil separators; impingement, helical, and coallescing.

OIL SEPARATORS


Impingement separators use screens in the upper half to cause fine particlesof oil to collect and form larger ones. The velocity of the discharge gas is reduced when it enters the large volume of the oil separator which helps theoil droplets to impinge on the screen. The droplets grow large enough in sizeto fall to the bottom. When sufficient oil has been collected a float operatedneedle valve opens and allows the difference in high side and low side pressureto return the oil to the crankcase. The black arrow in the graphic is above thefitting for the oil return line. Impingement separators are approximately 80% to 85% efficient and are in common use. The drawing shows a serviceabletype impingement oil separator. They are also available as a sealed unit.

Impingementtype


Helical separators (aka .. cyclone) depend on the interior shell designto force the refrigerant / oil mixture along a spiral path. That creates a centrifugal force which forces the lubricant droplets to the outsideof the spiral where they collect and drain to the float valve below.A supposed drawback to this type of unit is that centrifugal forceonly works effectively on relative large lubricant droplets. This meansthat smaller droplets remain in the refrigerant and are re-circulatedthrough the system. However manufacturers of helical separators claimthat up to 99% efficiency can be achieved.

Helical / Cyclonetype


In coalescing separators, the refrigerant/oil mixture is passed througha filter of exceptionally pure, extremely fine glass fibers, which forma capturing matrix. This matrix excites the oil molecules, causing themto collide and form larger droplets which are forced to the filter's outerdrain layer where they drain by gravity into the sump. Coalescing unitsare capable of delivering between 95% to 99%+ efficiency, dependingon the grade of filter core used and the design details. There are some coalescing oil separator manufacturers that claim their units have 99.99% efficiency.

Coalescingtype


Polly Ester

Polly’s unsavory background is that she’s nothing but acid and alcohol.Manufacturers have tried to neutralizer / stabilizer her for years. Shegoes everywhere and she’ll pick up anything and everything on her travels. She’s expensive, $ 40 to $ 50 per gallon. She sucks, veryhygroscopic as she picks up water readily. She’s a loud mouth,reciprocating compressors using Polly will be about 50% (1-1/2 times)louder on the dB scale as the same compressor using mineral oil. She’sa tramp, as Polly is polar in nature she will carry wear particulates insuspension as she flows throughout the system.

Let’s call her what she is, she’s a bitch.

Something to think about.


Grams or CC’s of H2O @ 20°C (68°F)

Pounds of Refrigerant

25 50 100 250 500 1000 2000

10 0.12 0.25 0.5 1.1 2.3 4.5 9.2

30 0.4 0.7 1.4 3.4 6.8 13.6 27.2

50 0.5 1.1 2.3 5.7 11.3 22.7 45.2

100 1.2 2.3 4.5 11.3 22.7 45.4 91

250 2.9 5.8 11.3 28.4 56.7 113.4 227

500 5.6 11.3 22.7 56.7 113.4 226.8 454

1000 11.3 22.7 45.4 113.4 226.8 453.6 907

1500 17.0 34.0 68.0 70.1 340.2 680.4 1361

2000 22.7 45.4 90.7 226.8 453.6 907.2 1814

ppm

H2O

Notes: 1 gram = 20 drops of H2O or 1 gram = 1 ccppm’s x weight x 453.59 ÷ 1,000,000 = grams or cc of H2O

POELubricant


Generally Accepted Piping Criteria

Inline flare by flare relief valves:

Under certain circumstances it may be necessary to install an inline relief differentialrelief valve. The purpose of this valve is to relief a situation where hydrostatic pressurecould develop due to liquid refrigerant being trapped leaving it no room for expansionas the temperature increases. This situation is usually caused by the systems pipinggeometry and/or installed ancillary devices.

Split system with buried piping:

In some installations it may become necessary to bury the line set. An example of thismay be under a sidewalk for safety reasons. If this situation arises use a minimum of 6 inch or larger diameter irrigation type tubing open at both ends above grade, this should provide adequate ventilation. The ends of this tubing can be covered with large mesh screening to keep small critters out but will allow adequate air circulation to preventthe condensation of refrigerant vapour in the underground section. Good installationpractice would also include the installation of a properly sized suction line accumulator.


Best Piping Practices

Liquid Line for Multi Evaporators

Split system A/C or Refrigeration

Multi-Evaporators Hot Gas

Liquid Line Stacked Evaporators

Suction Line Stacked Evaporators

How to Modify Defective Piping Installation

Split Circuited Condensers


Liquid Line Piping for Multi evaporators or cases with defrost

Refrigerant Piping Practices

Liquid Line

Liquid Line

Case coilCase coilCase coil

Case coilCase coilCase coil A

B

Denotes TEVcontinued …...


Liquid Line

Liquid Line



B

Denotes TEVcontinued …...




Liquid Line

Liquid Line



B8 inch

minimum

NO

“B” is recommended because liquid hammer will not effect the fittings also expansion and contraction will take place on liquid header not the branch fittings.

Denotes TEV

“A” is not recommended because of liquid hammer also expansion and contraction will “work” the elbow and cause a failure.




Split system, 100 ft apart, evaporator above condensing unit


Evaporator coil

Condensing unit

Evaporator coil A

B

Condensing unit

continued …...Denotes TEV


Split A/C system, 100 ft apart, evaporator above condensing unit


Evaporator coil

Condensing unit

Evaporator coil A

B

Condensing unit

90 feet

10 feet



Split A/C system, 100 ft apart, evaporator above condensing unit


Evaporator coil

Condensing unit

Evaporator coil A

B

Condensing unit

90 feet

10 feet

10 feet

90 feet

Note: 100 feet of 7/8 tubing will hold 25 pounds of liquid R-22 refrigerant.

“B” is recommended because only 10 ft of liquid refrigerant (10 % of 25 = 2.5 lbs) will drain on off cycle into condensing unit, less chance of damage on start-up.

Note: 100 feet of 7/8 tubing will hold 25 pounds of liquid R-22 refrigerant.

“A” is not recommended because 90 ft of liquid refrigerant (90 % of 25 = 22.5 lbs) will drain on off cycle into condensing unit,damage compressor on start-up.

Denotes TEV


Same Circuit Multi Evaporators with Hot Gas Defrost


Hot Gas Defrost Line

EvaporatorEvaporator

EvaporatorEvaporator A

B




Same Circuit Multi Evaporators with Hot Gas Defrost



EvaporatorEvaporator

EvaporatorEvaporator A

B


“A” is not recommended becausewhen the ‘Hot Gas” is off liquidrefrigerant can be feed from oneevaporator to the other evaporator.

“B” is recommended because thereis a check valve in the Hot Gas lineleading to the side inlet “Tee”.Thereby preventing liquid refrigerantfrom entering the other evaporatorwhen Hot Gas defrost is not in use.

Denotes TEV


Liquid Line Feed to Stacked Evaporator Coils


B

Condensing unitCondensing unitReceiver Receiver

Evaporator

Evaporator

Evaporator

Evaporator

Evaporator

Evaporator

A





A B


Evaporator

Evaporator

Evaporator

Evaporator

Evaporator

Evaporator





Evaporator

Evaporator

Evaporator

B


Evaporator

Evaporator

Evaporator

A

“A” is not recommended because of the “static head”ofliquid, only the bottom coil will receive a full column ofliquid, the middle would have liquid and some vapourand the top coil could receive little liquid and the majorityof the vapour therefore poor system performance. Vapourbubbles will rise to the top coil.

Note the receiver, because there is a two phase conditionin the receiver little or no sub-cooling is available.

“B” is recommended as all coils will be feed equalquality refrigerant therefore having balancedevaporators and good performance.

Denotes TEV


Suction Lines from Stacked Evaporator Coils



Denotes TEV

B

Evaporator

Evaporator

EvaporatorTEVbulb

Evaporator

Evaporator

Evaporator

ATEVbulb


Suction Lines from Stacked Evaporator Coils



Denotes TEV

The remote TEV bulbs and external equalizing line connectionsmust be located so that the conditions effecting one valve can-not influence the other valves. The double elbow configurationallows the corresponding section of the evaporator coil to drainfreely while isolating the remote bulb and equalizer line from the suction pressure and temperature of the above coil section.

Arrange the suction line so that the refrigerant vapour leavingthe top coil flows downwards, connection to the pipes leavingthe other coils. This manifold pipe should drop below the lowestcoil outlet before turning upward. This allows all of the oil todrain out of the evaporators and congregate before it must becarried up a vertical riser.

The single suction line then rises above the height of the evaporator coils, preventing refrigerant and oil inside the evaporator from free draining into the suction line, and towardsthe compressor, when the system is off.

Double elbow configuration

Must drop below lowestheader outlet

Must rise above height of evaporators

B

Evaporator

Evaporator

EvaporatorTEVbulb

Evaporator

Evaporator

Evaporator

ATEVbulb




Evaporator

Evaporator

Evaporator

Condensing unitReceiver

“A” is not recommended because of the “static head”ofliquid, only the bottom coil will receive a full column ofliquid, the middle would have liquid and some vapourand the top coil could receive little liquid and the majorityof the vapour therefore poor system performance. Vapourbubbles will rise to the top coil.

Note the receiver, because there is a two phase conditionin the receiver little or no sub-cooling is available.

Denotes TEV

" A "To the low side of system

Capped


Liquid line toremote evaporators

Receiver

Catch-All

See-All

Solenoid

Liquid Hammercan split LR 90º ells

" Stand pipe " of a minimum length (12”) will help prevent split ells caused by liquid hammer.

Problem


Owner


Roof Line

LiquidCondensate line

Receiver

Liquid Line

Suction Line

Discharge Line

Condenser

Compressor

Controlling Liquid Line Pressure

High Pressure Vapour LineORD - 4

ORI -Outdoorambient

Indoorambient

hot gas binging.ppt

Considerations: 1 pisg pressure lifts ref. 1.8 ft.Binding line equals pressure between receiverand condenser. If receiver 20 pisg higher ref.will not flow down.

ORD-4-20ORD-4-25ORD-4-30ORD-4-35

220205


ORD-4-35

ORD-4-20ORD-4-25ORD-4-30ORD-4-35

*

* is standard

ORD-4-35

DischargePressure240 psig

ReceiverPressure175 psig

" A "" B " " C "

Refrigerant Flow

Normal operation A to B is a ∆ 65 psigIf B pressure drops >5 ORD #1 opens

# 1 # 2

Series Refrigerant ORD Operation


Roof Line

LiquidCondensate line Hot Gas Binding Line

Receiver

Liquid Line

Suction Line

Discharge Line

Condenser

Compressor

Hot Gas Binding

High Pressure Vapour LineORD - 4

ORI -Outdoorambient

Indoorambient

hot gas binging.ppt

Considerations: 1 pisg pressure lifts ref. 1.8 ft.Binding line equals pressure between receiverand condenser. If receiver 20 pisg higher ref.will not flow down.

ORD-4-20ORD-4-25ORD-4-30ORD-4-35

220205

R-22

100 = 196105 = 210110 = 226115 = 242120 = 260125 = 278

226

ORI -


What Does This Tell You ?


Result …….


Refrigerant Migration Protection

A description of methods, using a Liquid Line Solenoid Valve (LLSV) installed in the liquid line just before the metering device, to prevent liquid refrigerant in the evaporator from flowing intocrankcase of the compressor during the off cycle and causing a flooded compressor start.

by Garth Denison

1. Solenoid Drop (minimum protection)

When the cooling thermostat is satisfied, the LLSV is de-energized closing off the liquid line. The compressor also cycles off. The closing of the liquid line prevents any refrigerant migration to the low side of the system. Since there maybe refrigerant remaining in the low side of the system which could migrate to the lubricant in the crankcase of the compressor, it is highly recommended that a crankcase heater be used with this system.

~

~

~

~

LLSV

CC

TC

L1 L2

Legend

CC – compressor contactorCR – control relayHP – high pressure contacts L1-L2 control powerLLSV – liquid line solenoid valveLP – low pressure contactsOL – compressor overloadsTC – thermostat cooling


2. Pump Down ControlWhen the cooling thermostat is satisfied, the LLSV is de-energized closing off the liquid line.With this control, the compressor remains operating drawing the refrigerant out of the low side of the system until the low side pressure is low enough to open the low pressure switch(LPS) stopping the compressor.

If the LLSV leaks, the low side pressure will increase to close the LPS starting the compressor.The compressor will continue to cycle as long as the LPS is closed. This repeated cycling will cause the compressor winding to overheat and lead to compressor failure.

Also, if the compressor is equipped with suction pressure unloaders, leaking through theunloader will cause the compressor to rapid cycle. Therefore it is not recommended to usea pump down control on a system with suction pressure unloaders.

~

~

~

~

CC

LLSV

TC

L1 L2

HP LP OL

Legend




3. Pump Out Control:

This system operates similar to the pump down control, only with a pump out control, a compressor lock-out relay is used to prevent the compressor from cycling on the LPS.With the lock-out relay, the compressor reverts back to the cooling thermostat control and will not restart until the thermostat senses a need for cooling.

A crankcase heater should be used in conjunction with the pump out control.

~

~

~

~CC

L1 L2

CR

TC

HP LP OL

LLSV

CR1

CR2

CC

Legend




Sound !!!!!


Harmonics … Pulsations What are They ?

Condensations and refractions are clusters of variouslengths of sound waves that catch up with each otherwithin the piping system. This causes the amplitude of the sound level to increase causing loud disturbingpulsating harmonic sounds.

Possible means of limiting or greatly reducing these harmonics.

• Add mass and additional clamping to discharge line, attach angle iron to the dischargeline with hose clamps. (eg: 10” x 1-1/2” x 1-1/2” x ¼” angle iron)

• Change discharge piping configuration, this changes length of reverberation channel.• Install sound pulsation plate between compressor and discharge service valve.

These plates are designed to create a 5 psi backpressure thereby changing the soundwave length and frequency that is being emitted from the compressor.

• Change compressor rotation as gas passages are not equal in length.• Move pressure operated unloader to other side bank.• Install large discharge muffler to smooth out pulsations.• Change the type of compressor from reciprocating to dynamic compression.• All field piping must be of “Prime” value, not divisible equally by 2, 3, 4 or 6. • A lubricant change will lower the sound level … R-22 POE to R-22 MO or AB


Discharge Pulsation PlatesCarlyle Compressors

06DA818 (6D48) is 5/16”06DA824 (6D68) is 3/8”06DA337 (6D73) is 7/16”06DA537 (6D75) is 7/16”

06E250 is 1/2” 06E275 is 5/8”06E260 is 9/16” 06E299 is 23/32”06E266 is 9/16”

All restrictor plates 1/8” thick, centre hole diameter as specified below.

1 ¾

” 2 ½

”

½” dia. (4)

⅜” dia.(2)

06D series06E series

Remember .. Two (2) service valve gaskets are required with each plate, one for each side when restrictor installed.


Mufflers & Baffle Plates

Discharge Pulsation PlatesCarlyle Compressors

Assist in pressure pulsation and sound reductions.Size mufflers per discharge line size or larger.Size baffle plates per application recommendations.

Baffle Platesaka .. pulsation plates

or muffler plates


Discharge Pulsation Plates

Copeland:Application Recommendations of Compressor Muffler Plates

Application Engineering Bulletin AE-4 - 1181


Discharge Pulsation PlatesCarlyle:

Application Recommendations With Baffle PlatesCarlyle Technical Bulletin 99T – 4


An Important IndustryDistinction

There is a common misunderstanding within the refrigeration industryaround the refrigerant Pressure Enthalpy (Ph) diagram. Some industryindividuals are under the impression that a refrigerant Pressure Enthalpy(Ph) diagram and a Mollier diagram are synonymous with each other. This is misleading and incorrect, they are NOT identical, nor are they interchangeable. The Mollier diagram is the European version of the Anglo-American Psychrometric chart. The Psychrometric chart and theMollier diagram are identical in content but not in appearance. Both thePsychrometric chart and the Mollier diagram deal with the properties andmeasurements of AIR not the properties and measurements of “Refrigerants”. Only the Pressure Enthalpy (Ph) diagram deals with theproperties and measurements of refrigerants.

Mollier diagramPh diagram

Something to think about.

An Important IndustryDistinction


Future … Crystal Ball

Around the Corner !!

R-404A

R-134a

Recovery

R-407C

R-410A

R-507A


When .. 5 ≈ 31+ ≈ 5 = 34

Years

R-11R-12R-22R-500R-502

1986

R-134aR-404AR-407CR-410AR-507

2020

R-123, R-124, R-125, R-134a, R-143a, R-218, R-400, R-401A, R-401B, R-401C,

R-402A, R-402B, R-403A, R-403B, R-404A, R-405A, R-406A, R-407A,R-407B, R-407C, R-408A, R-409A,R-410A, R-410B, R-412A, R-414A,R-414B, R-416A, R-417A, R-420AR-421A, R-422A, R-423A, R-424A.

Simplicity is Around the Corner

United Nation Environmental Program (UNEP) a.k.a. Montreal Protocol


Domestic / White goods, Vending:R-134a .. Rotary or Scroll

Auto A/C:R-134a .. Future R-744 (CO2)

Residential A/C & HP: < 5 tonR-410A .. Scroll

Commercial A/C & HP 5 thru 100 ton:R-410A .. Scroll, (Screws R-134a larger units)

Commercial Refrigeration:R-404A / R-507 Reciprocating or Screw,(Scroll under development)

Large tonnage 100 thru 10,000 ton:R-134a .. Centrifugal or Screw

Retrofit market:A/C DX applications .. R-407CA/C Flooded .. R-134aRefrigeration / Process .. R-404A / R-507

Application Future In North Americaas seen by Garth Denison

Original refrigerantsR-11R-12R-22

R-500R-502

Interim refrigerantsmorgasbord

(31+)

Future refrigerantsR-134aR-410A

R-404A / R-507R-407C

1986

2020


" What’s on the Horizon "

customer

System Engineer


CO2 Direct Expansion – MT and LT

LT 181 kWor

51.5 Ton


Graphic Representation of Compressing Details

CO2 or R-744 is a TranscriticalRefrigerant


MT CO2 Multi Compressor Set for Field Test .. Qo = 160 kW or 45.5 tons


ICE

Beautiful, Scenic, Dangerous,Hazardous, Costly

c:\sporlan 2006\cooling idiosyncrasiesBeautiful


Scenic


Dangerous


Hazardous


Frozen / Broken Waterline in Garage !!!!

Very Costly


LOOKING DEEP INTO PROBLEM AREAS


Refrigeration Ice Plants

Canary " Passing "

R-717 …. NO Contact LensesVaseline in groin and arm pits !

Safety Rope / Buddy System


When mixing a calcium chloride brine for freezing ice creamwith a desired freezing point of minus 30°F or lower is neededand no hydrometer is available use a large Irish potato, if the potato does not float in the brine mixture add more calcium chloride to the brine solution.

Calcium Chloride Brine minus 30°F


You exited FastFastBlue Dancing Flame

Methyl Chloride


SO2

Rats .. Cockroaches disappearedPlants .. Grass, Produce diedCanaries, Budges, Parrots goneLong hoses, water, open windows

SO2 no smell, carbon filters


Unique Historical ServiceTechniques

Do you remember: ………….

When hot water froze faster than cold water !!!

Temper proofing controls .. clear nail polish.

Service trucks carried sanitary napkins (Kotex)

Service trucks carried feminine deodorant spray (FDS)

Service trucks carried petroleum jelly (Vaseline)

Service trucks carried Vicks Vapor Rub or Basil


You ARE the Perfect HVAC&R System

Compressor _________________Controller ___________________Control system _____________Piping network _Refrigerant ______________Evaporator ____________Lubricant _______Condenser __________________Head pressure ________Capacity control __________Filter / Drier _________________Purge system _______________Power supply _________________Fine Tuning _______________

HeartBrain

NervesCardiovascular system

Life bloodSkin / Sweat

(LDL / HDL) CholesterolLungs

Blood pressureHeart rate

LiverKidney

DietExercise

Comparing Systems

" Education is Just the Beginning "Modern ServiceTechnician


Diagnostic Means

Manifold gauges _______________Periodic check __________________Thermometer ___________________________Fluid ailments (refrigerant, lubricant, H2O) _______Touch, Sound, Sight, Smell _____________________Maintenance ________________________Superheat / Sub-cooling _________________________Sight glass _____________________________Know how / Experience, Intuitiveness _____Preventative Care _________________________

Manometer / StethoscopeNon-destructive testing

TemperatureLaboratory analysis

SensesRoutine physicals

PulseMRI / X-Ray

Diagnostic skillsMedication


You ARE the Perfect HVAC&R System

" Education is Just the Beginning "


Cold W.A.R. IntroducedJune 2003

W hether it’sA ir ConditioningR efrigeration


Sporlan Division of Parker Hannifin has introduced a new service oriented no charge information support program titled“Cold W.A.R.” This monthly e-mail based only information network program is designed to provide you, the service technician, with a collection of associated technical informationtopic papers in a simple comprehensive format. Don’t miss thisopportunity to increase your existing knowledge base. Sign uptoday and start receiving your personal direct e-mail copy.


Second Tuesday each month

[email protected]

NEW


CONCLUSIONHaving been through this presentation,

it would be quite natural for you toconclude that it is virtually

impossible to design aperfect refrigeration

system.

This is probably true.


“Refrigerant molecules are square, through constant and continuoususe the corners are rounded off, that’s why you need to add

additional refrigerant !!"

This reaction is similar to a box of cereal, it started off fullbut through constant moving and shaking

it settles and now looks only half full.

Why do I need to continuously add morerefrigerant every year?


Customer


Why do Women Live Longer

then Men ?


Visit us at www.sporlan.com

The Sporlan Valve Division, Parker Hannifin assumes no obligations or liability for any advice furnished or for any results, property damage or personal injury including death that may result with respect to the use of this information. All such advice is given and accepted at users risk. This disclosure of information herein is not a license to operate under, or a recommendation to infringe any patent of Sporlan Division of Parker Hannifin or others.

Dated May 2006Supersedes

® Registered trademark of Sporlan Valve Division, Parker Hannifin Corporation, Cleveland Ohio USA© Copyright 2005 by Sporlan Valve Division, Parker Hannifin Inc

Cooling system idiosyncrasies 2006

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