Application Bulletin 140

7/28/2019 Application Bulletin 140

1/12

Revision V29902 Application Bulletin 140

Page

H20J/H21J and H70J/H71J Series

ApplicationBulletinApplicationBulletinApplicationBulletinApplicationBulletinBENCHMARKCompressorwithRefrigerantsR22andR407C

OVAL HOUSING(14,000 ~25,000 BTU/Hr.)

ROUND HOUSING(~25,000 44,000 BTU/Hr.)


2/12


Page2

ApplicationBulletinApplicationBulletinApplicationBulletinApplicationBulletin Number: 140Release EN: M02108Date: 3/12/04Revision EN: V29902Date: 1/3/12

Subject: H20J/H21J and H70J/H71J Series CompressorApplications with Refrigerant R22 and R407C

This Application Bulletin is for air-to-air air conditioning and heatpump applications only. For other applications or deviations

from this Bulletin, please call Bristols Applications EngineeringDepartment at (276) 466-4121.

The BENCHMARK R22 reciprocating compressorcan berecognized by the number 2 in the secondcharacter and with the letter J in the fourth charac-ter of the compressor model number (example: H20Jor H21J223ABCA). The BENCHMARK R407Ccompressor can berecognized by the number 7 inthe second character of the compressor model num-ber (example: H71J223ABCA). Innovative mechani-cal design and gas management make theBENCHMARK compressor very efficient. Not onlyis the sound level (dB) lower than previous productsbut the sound content (frequency) delivers excep-tional acoustical characteristics. The following guide-lines were developed for the BENCHMARKH20/21J/71J series compressors through systemtesting as well as laboratory testing with model spe-cifics highlighted where applicable.

For the purpose of explaining the features of the twoBenchmark configurations, this bulletin uses twodistinct product differentiators.

OVAL HOUSING

Smaller capacity

Internal muffler

ROUND HOUSING

Larger capacity

Requires External muffler

Note: Non-compliance with this document does notnecessarily void the compressor warranty. Its primarypurpose is to provide the system designer with guide-lines that help assure the integrity of the final product.

1.0 Crankcase Heat

The refrigerant charge limit is published on the indi-vidual compressor specification sheet. Total chargeincludes the allowance for the tube size and lengthplus the tolerance of the charging equipment.Acrankcase heater is not required on systems when thetotal system charge is below the compressor chargelimit. For applications that require a crankcase heater,insertion type PTCR (Positive Temperature Coeffi-cient Resistance) crankcase heaters are available.

Refer to the individual compressor specification sheetfor the heater part number and wattage rating. To in-crease the longevity of the compressor bearings, acrankcase heater is recommended to prevent liquidrefrigerant from migrating into the compressor. Liquidrefrigerant can dilute the oil causing excessive bear-ing wear. Refer to Application Bulletin 135, CrankcaseHeaters.

2.0 Motor Overload Protection

The BENCHMARK compressors are protected byinternal line break overload protectors that sense mo-tor winding temperature and current. These protec-tors are automatic reset devices containing a snapaction bimetal switch. They are designed to interruptmotor current under a variety of fault conditions suchas: failure to start, running overload, fan failure and

loss of charge. In three-phase compressors, thesedevices provide protection during transformer primaryand secondary single-phase conditions.


3/12


Page3

The following tests are for all systems includingthose designed with an accumulator. These testsare used to determine if the system needs design

change. Bristol testing has indicated thatadding an accumulator as the only solutionto excessive flooding, in most cases, is inade-quate. Two excessive liquid floodback tests arerequired on heat pumps: one for the heating modeand one for the cooling mode. Air conditionerswill require the cooling test. Non-reversing heatpumps will require only the heating test. The testset up is the same for heat pumps and air condi-tioners. Before starting the test, thermocouples(TCs) should be attached to the suction and dis-charge tubes approximately 6 to 8 inches (15 to20 cm) from the compressor. A TC should also be

attached to the sump of the compressor (as closeto bottom center as possible, all TCs must beinsulated). The system charge for this test shouldbe adjusted to represent the equipments worst-case flood-back field condition. This test shouldsimulate the affect of refrigerant overcharge, orother variables that could result in inadequatesuction superheat at the compressor.

Bristol recommendations:Add 10% greater charge than design specificationsfor non-TXV metering devices and 20% greater

charge for TXV metering. The evaporator should beelevated 5 feet (1.5 m) above the condensing unitwith a 25-foot (7.6 m) line set to verify the evaporator

out tubing configuration does not allow liquid to flowout of the coil and down the suction line into the com-pressor under these flooded coil conditions (again,use of a suction sight glass is highly recommended).

If the sump T or discharge superheat values arebelow the following guidelines, the system designmust be changed.

Minimum Sump TSump temperature should be 30F (16.7K) warmerthan the saturated temperature equivalent of the suc-tion pressure.

Minimum Discharge SuperheatDischarge temperature should be 50F (27.7K)warmer than the saturated temperature equivalent ofthe discharge pressure.

3.0 High Pressure Protection

BENCHMARK compressors are equipped with aninternal pressure relief valve (IPRV) sensitive to ex-cessive discharge pressure. High pressure gas is by-passed internally if the differential open setting isreached. The valve will open between 450 and 550psig (32-39 kg/cm2) pressure differential, (Example:With a suction pressure of 84 psig (6 kg/cm 2), the in-ternal relief will open at 534 to 634 psig (38-45 kg/cm

2). The IPRV resets automatically when the fault

condition is corrected. Such fault conditions are:condenser fan failure, dirty or restricted condenser

coils, refrigerant overcharge and discharge restriction.If the IPRV is the primary system protection, the fol-lowing test must be performed: (1) Operate the sys-tem at the highest outdoor and indoor ambient thatthe system will experience, (2) Simulate a failed con-denser fan motor by disconnecting the fan motor.Heat pumps will require simulating the outdoor unitmotor failure in cooling and the indoor unit motor fail-ure in the heating mode. It is recommended that allcommercial installations incorporate low and highpressure manual reset safety switches.

4.0 Accumulators

All heat pump systems require an accumulator.Other systems should be evaluated per Applica-tion Bulletin 101, to determine if an accumulatorwill be required. Cooling-only systems with a total

charge less than the compressor charge limitationnormally will not require an accumulator. A double-sided see-through sight glass installed in the suc-tion line of a test compressor, will assist the sys-tem designer in observing liquid refrigerant flow-ing into the compressor during system testing.

Large volumes of liquid refrigerant repeatedlyreturning to the compressor during the off-cycle,defrost cycle or excessive floodback duringsteady operation can dilute the oil to the point

that the bearings are inadequately lubricated.These conditions cause excessive bearing wear.

5.0 Excessive Continuous Liquid Floodback Tests


4/12


Page4

The purpose of this test is to determine how muchliquid actually gets into the compressor during sys-tem on/off cycles. This test should simulate the af-fect of refrigerant overcharge, or other variables that

could result in inadequate suction superheat at thecompressor and cause slugging. To complete thistest, a sample compressor must be obtained with asight tube to measure the liquid level in the compres-sor or set the compressor on calibrated scales tomeasure the weight. The refrigerant charge shouldbe adjusted to represent the amount that the systemmight experience in a worst case field overchargescenario.

Bristol recommendations:10% greater charge than design specifications fornon-TXV metering devices and 20% greater charge

for TXV metering. The evaporator should beelevated 5 feet (1.5 m) above the condensing unitwith a 25-foot (7.6 m) line set. Operate the system inthe cooling mode for 1 hour before testing at each of

the ambient temperatures indicated in Table 1 below.Shut the outdoor unit off (compressor and fan). Keepevaporator blower running. System on/off time andnumber of cycles are different for each of the 3 testsshown in Table 1. Observe and record the amount ofliquid refrigerant (height or weight) at the start of eachon cycle. If the compressor slugs or makes a metallicsound on start-up, system design change is required.

Set up the test unit to operate under a worstcase set of conditions that will produce an out-door coil frost condition. This scenario shouldtake into account high humidity, low temperatureconditions and reduced airflow across the outdoorcoil in order to evaluate the affect of blocked out-

door coils.

Bristol recommendations:The defrost control must be disconnected to prevent

unit from defrosting. Outdoor ambient should be 17FDB (-8.3C), 15F WB (-9.4C) and indoor ambient70F DB (21.1C), 60F WB (15.5C) maximum. Out-door unit fan motor should be disconnected to simu-late a blocked evaporator coil. Operate unit until pres-sures and temperatures are stabilized and verify the

Sump T and Discharge Superheat, as notedabove, exceed the minimum values.

This test should simulate the affect of reducedairflow over the indoor coil (i.e., dirty filter, ob-structed coils, faulty duct work, etc.) and the re-sulting decreased suction superheat at the com-pressor. The evaporator airflow should be re-duced to levels the system might experience in a

worst case field scenario.

Bristol recommendations:Operate the system for 1 hour; outdoor unit should bein 95F (35C) DB, 75F (23.9C) WB ambient and

indoor unit at 67F (19.4C) DB, 57F (13.9C) WBwith evaporator airflow reduced to 50% to simulatedirty return air filter. Verify the sump T and dis-charge superheat, as noted above, exceed the mini-mum values.

6.0 Excessive Liquid Floodback Cycling Test

Heating Mode Excessive Continuous Liquid Floodback Test

Cooling Mode Excessive Continuous Liquid Floodback Test

TABLE 1EXCESSIVE LIQUID FLOODBACK CYCLING TESTS

Test No. 1 No. 2 No. 3

Indoor Ambient (F) 70 (21.1C) 70 (21.1C) 70 (21.1C)

Outdoor Ambient (F) 85 (29.4C) 95 (35C) 105 (40.6 C)

System On-time (Minutes) 7 14 54

System Off-time (Minutes) 13 8 6

Number of On/Off Cycles 5 5 4


5/12


Page5

An innovative starting concept has been devel-oped by Bristol Compressors that eliminates thecompressor start components (start capacitor/relay) required for systems using non-bleed typeexpansion valves. This optional feature is avail-

able on select BENCHMARK models. They areidentified by the letter B in the seventh charac-terof the model number (H2*J**B). These Bleedcompressors are designed to internally equalizeby utilizing an external check valve in conjunctionwith a non-bleed type TXV. Bristol recommendsthe check valve to be installed on the compres-sors discharge connector tube (or as close aspossible) in order to minimize pressure equaliza-tion time across the compressor valves.

It is recommended that each OEM perform starttests at their worst case condition to assure no

issues with their placement of the check valve. Itis also important to determine if the equalizationtime is acceptable with the check valve moveddownstream of the compressor discharge connec-tor. This technique will help maintain system oper-

ating pressures during the off-cycle, thus improv-ing the SEER performance by decreasing CD. Theinternal equalization is transparent to the customerand requires no special attention.

Bleed Compressors with Oval HousingOnly an external check valve is required since thesemodels employ an internal discharge muffler.Again, the check valve may be installed at any pointin the hot gas line, preferably as close to the com-pressor discharge connector as possible. See Table 2for recommended check valves.

The BENCHMARK models do not require start com-ponents on systems where the pressure equalizescompletely in the off-cycle. For single-phase applica-tions, a low torque PTCR can be used if only a lightassist is needed, as in the case of a low voltage con-dition. If a non-bleed expansion valve is used, orother reasons exist that will not allow pressure equali-zation prior to compressor start-up, then a start ca-pacitor and potential relay are required (Exception:

see Section 8 for an option to eliminate starting com-ponents) . High torque start components are avail-able for the BENCHMARK model. The PTCR andstarting components are listed under the ElectricalAccessory Components section of the individual com-pressor specification sheet. This information can beobtained via Bristols web sitewww.bristolcompressors.com or directly from BristolCompressors.

8.0 Start Component Elimination

7.0 Starting Characteristics

Recommended sources for the electrical components are:

Source for the PTCR 305 Series

Ceramite Corporation1327 6th AvenueP. O. Box 166

Grafton, WI 53024-0166Phone: (414) 377-3500Web: www.ceramite.com

Source for the GE Relays

General ElectricAppliance Control DivisionWest Wall Street

Morrison, IL 61270Phone: (815) 772-2131Web: www.ge.com

Source for the Electrica Relays

Manitowoc Relay & Protectors, Inc.1429B Wentker CourtP.O. Box 146

Two Rivers, WI 54241-0146Phone: (920) [email protected]


6/12


Page6

Round Housing

Bristol Compressors research has proven that theuse of an external discharge muffler is far superior tothe internal style. This is due to the space limitationand fixed location within the hermetic shell. The ex-

ternal muffler approach gives the system designer theopportunity to utilize the most effective muffler typeand location. The round housing BENCHMARKmodels do not employ an internal discharge mufflerand require that an external muffler be preciselyplaced in the discharge line as illustrated in Figure 1.The noted dimension A is to be used for the follow-ing tubing placements:

For 60 Hz applications, install assembly with 13inches (2 in.) or 33 cm (5cm) of tubing betweenthe discharge tube outlet and the muffler.

For 50 Hz applications, install assembly with 20inches (2 inches) or 50.8 cm (5 cm) of tubing be-tween the discharge tube outlet and the muffler.

The muffler must be UL/CSA certified for use as ahigh-side component for the intended refrigerant ap-plication.

Bleed Compressors with Round HousingThese models do not employ an internal discharge

muffler; therefore they require one of the followingoptions:

1) An external discharge muffler with integralcheck valve installed per Section 9. See Table 4 fora listing of these mufflers and check valve assemblieswhich integrate the individual components into onecompact part thus reducing the number of brazejoints. Properly installed, this method is effective forreliable starting without a start capacitor/relay at allexpected differentials. The required time for internalcompressor equalization depends on the specificpressure differential when the compressor cycles off.To assure pressure equalization, a minimum fiveminute delay is recommended to avoid short-cycling.

However, if mufflers (with integral check valve) that

have larger volumes than noted in Table 4 are em-ployed, a longer time delay may be needed to assureequalized pressure at start up. This is important sincethe muffler volume is on the compressor side of thecheck valve with this integrated design.

2) A check valve installed as close to the compres-sor discharge connector as possible, along with aseparate discharge muffler installed downstream(muffler must be installed as illustrated in Section 9).

System designers must perform system evalua-tions to assure the pressures are equalizedacross the compressor before each compressorstart-up and to set their time delay accordingly.

9.0 External Discharge Muffler Requirement

TABLE 2CHECK VALVES FOR BLEED COMPRESSORS

Bristol PartNumber

Manufacturer MaterialManufacturers

Part Number

MufflerDiameter(inch/cm)

Length (inch/cm)

Inlet/Outlet ID orOD (inch/cm)

Internal FreeVolume

(inches3/cc)

NAMueller

RefrigerationCopper A-17936 1.125 / 2.85 5.23 / 13.28

Inlet/Outlet:.50 / 1.3 ID

2.5 / 41

250554Henry

TechnologiesCopper MS-887 1.125 / 2.85 3.75 / 9.52

Inlet: .50 / 1.3 IDOutlet: .50 / 1.3 OD

1.5 / 24

NAHenry

TechnologiesCopper MS-8 1.25 / 2.85 3.75 / 9.52

Inlet/Out:.50 / 1.3 ID

1.5 / 24

Note: The above check valves may be used with products that employ an external muffler (see detailsbelow).

Note: See recommended sources on page 11 for all external components shown in Tables 2, 3 and 4.


7/12


Page7

A filter-drier in the discharge line may be sub-stituted for the external muffler, if system test-ing confirms that the filter-drier provides ac-ceptable discharge pulse and sound attenua-tion.

If components other than those recom-

mended in Tables 2, 3 and 4are utilized,Bristol advises the use of a high quality, non-positional check valve designed for near-zeroleak rates. The muffler and check valve mustbe UL/CSAcertified for use as high side com-ponents for the intended refrigerant applica-tion.

Increased internal free volume or multi-chamberstyle discharge mufflers may provide superiorresults.

IMPORTANT NOTES:1) It is preferable that the muffler be installed as

shown in Figure 1 with use of the mufflers shownin Table 3. However, if it is necessary thatbends be placed in the tube between the com-pressor and the muffler, both indoor and out-door sound evaluations must be performed toconfirm acceptance of the final configuration.

Bristol field testing indicates any bends priorto the muffler can result in increased soundand tubing vibration, primarily with coppermufflers.

2) If the Sporlan muffler Part No. M-16E32 (see Ta-ble 3) is used, the DIM A tube may be reduced toa minimum length of 9 inches. No bends wouldbe allowed in the tube between the compres-sor and the muffler.

3) The tubing design between the compressor andthe condensing unit coil is very important in regard

to both sound performance and reliability. Thelength, number of bends, geometry, and method ofattachment can have a significant impact onacoustic performance of the muffler and tube vi-bration levels. The system tubing vibrationshould be thoroughly evaluated using acceler-ometers. Discharge tube total displacement (peak-to-peak) needs to be kept below 0.011 inches (asmeasured 3.5 inches from the top of the compres-sor discharge elbow) to avoid premature tubingfailure due to excessive vibration.

4) Use of only an external discharge muffler (i.e. no

check valve) applies only to models that do nothave a B in the seventh character of the modelnumber, refer to Section 8.

Oval HousingThe oval housing models do not require an exter-nal discharge muffler for 50 or 60 Hz.

The Table 3 generic muffler recommendations arebased on Bristol sound test evaluations with vari-ous systems. The Sporlan M-16E32 yielded thebest overall field results. Operational character-istics can vary between different system types andapplications. The OEM system designer must per-form sound tests to determine the best muffler con-figuration and optimize its location in the dischargeline to satisfy their particular design requirements.All available options should be thoroughly evalu-ated and the following considered:

A heat sink is required to prevent internalcheck valve damage during brazing

Do not use ball type check valve

FIGURE 1

Discharge Muffler or

Muffler/Check Valve

DIM A


8/12


Page8

H20J/H21J Series Compressor Applications with Refrigerant R22H71J Series Compressor Applications with Refrigerant R407C

PRODUCT GUIDE FOR TABLE 3

Application Cooling Only Heat Pumps

VoltageFrequency

60 Hz 50 Hz 60 Hz 50 Hz

Muffler*Tube Length*

Dim - AMuffler*

Tube Length*Dim - A

Muffler*Tube Length*

Dim - AMuffler*

Tube Length*Dim - A

Round CompressorHousing

A 13 2 B 20 2B

C (optional)13 2

BC (optional)

20 2

Oval CompressorHousing

External MufflerNot Required




Note: Use above Product Guide Letter designation in choosing muffler in Table 3 below.

*See Section 9.0 for further details on muffler and tube length.

TABLE 3

EXTERNAL MUFFLER ONLY

ProductGuideLetter

BristolPart

NumberManufacturer Material

ManufacturerPart

Number

Muffler OD(inch/cm)

Length(inch/cm)

Inlet andOutlet ID(inch/cm)

Internal FreeVolume

(inches3/cc)

A 302140 Parker Copper 031780-00 1.6 / 4.1 4.4 / 11.1 .50 / 1.3 5.4 / 88.5

A 302164 Kraftube Steel EM-20-2.605-000 2.1 / 5.4 4.9 / 12.4 .50 / 1.3 9.9 / 162.2

B 302146 Parker Copper 058750-00 2.0 / 5.1 6.5 / 16.5 .50 / 1.3 13.3 / 218.0

B 302165 Kraftube Steel EM-20-4.725-00-0 2.1 / 5.4 7.0 / 17.8 .50 / 1.3 15.8 / 258.9

C 302169 Sporlan SteelM-164-S orM-16E32

3.0 / 7.6 6.0 / 15.0 .50 / 1.3 24 / 393.0

C 302167 Kraftube Steel EM-30-4.250-00-0 3.1 / 7.9 6.5 / 16.5 .50 / 1.3 35 / 573.5

TABLE 4

EXTERNAL MUFFLER WITH INTEGRAL CHECK VALVE(for use only with round housing compressors with bleed)

Bristol PartNumber

Manufacturer MaterialManufacturer

PartNumber

Muffler OD(inch/cm)

Length(inch/cm)

Inlet andOutlet ID(inch/cm)

Internal FreeVolume

(inches3/cc)

250577 Superior Copper 900RGN-8S 1.63 / 4.14 7.88 / 20.0 .50 / 1.3 9.7 / 159

250578 Mueller Copper A-18051 1.63 / 4.14 7.88 / 20.0 .50 / 1.3 9.6 / 157

250576Henry

TechnologiesCopper MSM-11 1.63 / 4.14 7.88 / 20.0 .50 / 1.3 9.9 / 162

Note: Direct muffler orders to manufacturers should reference the manufacturers part number.


9/12


Page9

The BENCHMARK model compressors are excel-lent choices for field replacements and efficiency up-grades. The larger capacity models are specificallydesigned with the external discharge muffler concept

to achieve exceptionally quiet operation while main-taining high efficiency. When used as a replacement

for compressor models in systems not equipped withan external discharge muffler, the proper external dis-charge muffler and mounting componentsshould besupplied with the compressor and accompanied with

detailed installation instructions.

BENCHMARK compressors are designed to operatewithin a specific range of operation or envelope. Sys-tems must be designed so that the compressor doesnot operate outside the envelope or continuously atits boundary. Reference the individual compressormodel specification sheet for the operational enve-

lope, which is available at

www.bristolcompressors.com or may be obtaineddirectly from Bristol Compressors. Any deviation fromthe published limits must be evaluated and approvedby Bristol Compressors.

13.0 Field Replacement

10.0 Operation Envelope

11.0 Power Terminal Cover

Only the Bristol Compressors approved power termi-nal cover/retainer should be used unless written

approval is provided by Bristol Compressors for analternative.

Although the BENCHMARK model compressors areinternally isolated and the vibrations transmitted to the

shell are exceptionally low, external mounting isola-tors (grommets) are required. These resilient typemounts have been specially developed to isolate thecompressor from the system chassis and increase

reliability. Refer to Application Bulletin 112 for guid-ance on selection of isolators.

Customers preferring alternative mounting isolatordesigns should thoroughly test to ensure satisfactoryperformance.

12.0 Mounting Isolators


10/12


Page10


11/12


Page11

Recommended sources for check valves, mufflers, and muffler/check combinations:

Henry Technologies701 S. Main Street

Chatham, IL 62629(217) 483-2406www.henrytech.com

Mueller Refrigeration Company, Inc.121 Rogers Street

Hartsville, TN 37074(800) [email protected]

MUFFLER ONLY

Parker Hannifin17325 Euclid AvenueCleveland, OH 44112(800) 272-7537www.parker.com

Sporlan Valve Company206 Lang DriveWashington, MO 63090-1040(636) 239-1111www.sporlan.com

Kraftube925 E. Church AvenueReedy City, MI 49677(231) 832-5562, Extension 110www.kraftube.com

MUFFLER + CHECK VALVE COMBINATION

Mueller Refrigeration Company, Inc.121 Rogers StreetHartsville, TN 37074(800) [email protected]

Superior Sherwood Valves2111 Liberty DriveNiagara Falls, NY 14304-3744(716) 505-4800www.sherwoodvalves.com

Henry Technologies701 S. Main StreetChatham, IL 62629

(217) 483-2406www.henrytech.com

CHECK VALVE ONLY


12/12


P 12

REVISIONS

M23602 11/12/04 U15902 7/30/10

V29902 1/3/12

Release EN Number M02108 Release Date 3/12/04

Application Bulletin 140

Documents

Transcript of Application Bulletin 140