WARM Program Combustion Safety Testing Field Training October 21, 2008 Holiday Inn Conference...
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Transcript of WARM Program Combustion Safety Testing Field Training October 21, 2008 Holiday Inn Conference...
WARM ProgramCombustion Safety Testing
Field TrainingOctober 21, 2008
Holiday Inn Conference Center, New Cumberland, PA
Controversial and Confusing►Action Levels vary
►Terminology varies
►What do you do with unvented appliances?
►What do you do with coal stoves?
►How do you seal test holes?
►How far should WARM go to fix problems?
WARM Procedure
►Combustion safety testing has been required as part of the WARM program for many years.
►The procedure and action levels have recently been changed slightly.
Why Focus on Combustion Safety Now?
►Due to high natural gas and oil prices, more WARM customers have switched to using electric space heaters for their primary or sole heat.
►They then qualify for air sealing and insulation if their winter seasonal use is at least 2,000 kWh.
►But they likely have a gas water heater and may still use their fossil fuel heating system….
►So… if you air seal a home with a fossil fuel system, ……..
Why Now? ContinuedSo…..
►When air sealing or insulation is installed in a home with fossil fuel heating or water heating systems, the air exchange across the thermal boundary will (should) be reduced as part of the WARM installed measures.
►Any planned reduction in air flow (CFM -50Pa) means the combustion appliances must be checked BEFORE air sealing to be sure they are operating safely…. And they need to be checked AFTER air sealing to be sure they still operate safely.
Because…►Air is needed for proper combustion.►When air flow is restricted, combustion
appliances can be starved for air.►If a combustion appliance is starved for air, it
won’t burn properly and/or it pulls its combustion air down the flue and back-drafts.
►Back-drafting (spillage) is dangerous because the flue gasses contain CO and other bad things.
►We want to be sure the appliances operate safely.
Why Now? continued
Also, if a customer’s summer seasonal use is at least 2,000 kWh, they qualify for cooling load reduction measures, including insulation and air sealing measures. These customers may have fossil fuel heating systems and/or water heaters.
More Why Now?
►Utilities and other PA programs are requiring Energy Auditors and Field Technicians to be BPI Building Analyst 1 Certified.
►Following BPI Standards for combustion testing and safety makes sense in PA right now.
Which WARM Customers Get Combustion Testing?
Typical jobs:
►Defacto electric heat jobs
►Electric heat jobs with gas water heaters
►AC jobs receiving air sealing or insulation
Combustion Testing Includes:
►CO testing: ambient air, combustion appliance zone (CAZ), flues
►Gas leak detection
►Spillage and flame roll-out evaluation
►CAZ depressurization
►Draft evaluation
►Gas range testing
Combustion Safety TestingAudit Form Page 18
Combustion Safety Tests must be
performed if:
►Conventionally vented combustion appliances exist and
►Air sealing is done – to reduce cooling load or to reduce heating load
Audit Form Page
ProcedureCOMBUSTION SAFETY
SEPTEMBER, 2008This section includes specifications relating to combustion appliance
testing, related services and measures, and instructions for action when an unsafe condition is discovered.
COMBUSTION SAFETY TESTING PROCEDURE The WARM Program Service Delivery Contractors and QA contractors
must follow the most current Building Performance Institute (BPI) Combustion Safety Test Procedure for Vented Appliances and Combustion Safety Test Action Levels which served as a basis for this detailed procedure. For the purposes of this document, BPI’s Combustion Safety Test Procedure for Vented Appliances, dated 4/07, BPI’s Technical Standards dated 2/28/05, and BPI’s Combustion Safety Test Action Levels document dated 4/07 were used. …….
Action Levels
The Big PictureWhy Perform Combustion Safety Tests?
►When inadequate oxygen is present, in addition to CO2 being formed, Carbon Monoxide (CO) can be formed. This is our main concern.
►Carbon rich fuels, like Fuel Oils, can also lead to Carbon Particles, or Smoke, being produced.
Combustion DiagramThe ideal operating range is a setting with excess air.
Incomplete Complete
Excess Fuel Excess Air
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Courtesy of Bill Spohn, Testo
Air Tight Building►Negative pressure
conditions in homes can create back-drafting of combustion appliances
►Common exhaust equipment (i.e. attic fan, bathroom exhaust, fireplace) can compete with the normal venting process of combustion appliances
Graphics © COAD 1996
Courtesy of Bill Spohn, Testo
Sometimes Things Go Backwards
►Back-Draft
►Flame Roll-Out
►Spillage
Graphic © Readers Digest
2001
Courtesy of Bill Spohn, Testo
Combustion Testing Video
►16 minute video demonstrating the combustion safety testing procedure
What is flue gas?
carbon
hydrogen sulfur
oxygen
nitrogen water
Oxygen(20.9%)water vaporNitrogen (79%)
Carbon dioxide CO2
Carbon monoxide CO
Sulfur dioxide SO2
O2 - balance
Nitrogen oxide NOx
Water vapor H2O
Smoke (oil systems)
fuel-residualashes
fuelair
How is it formed?
Courtesy of Bill Spohn, Testo
What is Carbon Monoxide ?►CO originates from incompletely (oxidized) burnt
carbon (fuel). ►It is very dangerous for human and animals,
because it prevents the absorbstion of oxygen in the blood stream.
►Reasons for the formation:- fuel rich mixture- Improper venting- too early cooling of the flame (1128 F)
CO is expressed in parts per million (ppm).
Courtesy of Bill Spohn, Testo
CO Sources►Fuel burning furnaces
and hot water heaters►Fuel burning boilers►Fuel burning space
heaters►Kitchen ranges & ovens►Auto emissions
Attached garages
►Fireplaces►Tobacco smoke
Courtesy of Bill Spohn, Testo
Characteristics of CO
►Odorless►Colorless►Tasteless►Mixes well in air
Does not stratify
Follows air flow in a structure
►Poisonous
Courtesy of Bill Spohn, Testo
CO Health Effects► 35 ppm NIOSH Permissible Exposure Limit – 8 hours► 200 ppm NIOSH Ceiling– 15 minutes► 200 ppm Slight headache with 2-3 hours► 400 ppm Headache within 1-2 hours► 800 ppm Sickness & twitching of limbs within 1-
2 hours; unconsciousness in 2 hours► 1,600 ppm Headache within 20 minutes; death
within 2 hours► 3,200 ppm Death in 30 minutes► 6,400 ppm Death in 10-15 minutes► 12,800 ppm Death in 1-3 minutes
Courtesy of Bill Spohn, Testo
CO Testing Fuel Burning Appliances
►Sample from entry of home to exit of home
►Sample around all un-vented appliances
►Sample before draft diverter of atmospheric devices
►Sample where you may suspect CO
Graphics © COAD 1996
Courtesy of Bill Spohn, Testo
Types of Furnaces ►Atmospheric – Natural Draft
Buoyancy Creates NEGATIVE Pressure in Flue
►Induced Draft Fan Creates NEGATIVE Pressure in Flue
►Power Draft –Power Vent Fan Creates POSITIVE Pressure in Flue
►Condensing Sealed combustion
Calculating Combustion Efficiency
Natural GasLight OilHeavy OilPropane
Wood
Ambient Temp(combustion air)
Oxygen O2
StackTemp
fuelAir Temp
The analyzer uses the oxygen and net temperature measurements in fuel specific equations to give the efficiency, CO2 and excess air readings.
Courtesy of Bill Spohn, Testo
Combustible Gas Leak Detection
Spillage, Flame Roll-Out, Backdrafting
Testing for CO in the Appliance
►Test undiluted CO
Testing Draft
Notice the hole in the boiler flue pipe
Testing Draft►Some combustion analyzers test for pressure as well as
CO. This one records pressure (draft) in Inches of Water Column, IWC
Testing Condensing Furnaces►Test under Steady State
Operating Conditions►Sample around burner (CO)►Sample efficiency in plastic
vent pipe (MFG or authority)►Or sample in stack termination
(CO)
Follow Manufacturer’s Specs
Graphics © COAD 1996
Courtesy of Bill Spohn, Testo
Venting Types Video
►17 minute Gas Venting video
Gas Appliance Categories►Cat. I fan-assisted gas appliance: negative pressure,
a high vent temperature avoiding condensation and an integral fan drawing combustion air through chamber
►Cat. I gas appliance: negative pressure, a high vent temperature,
►Cat. II gas appliance: –negative pressure, low vent temperature causing excessive condensation
►Cat. III gas appliance: –positive vent pressure in the vent , a high vent temperature
►Cat. IV gas appliance: - positive vent pressure in the vent low vent temperature causing excessive condensation
Courtesy of Bill Spohn, Testo
Unvented Appliances – Test Air-Free or Undiluted
►Gas RangesCO Hot-Pot
www.karg.com
►Gas Ovens
►Test CO Air free, undiluted
Courtesy of Bill Spohn, Testo
Range Top CO Testing
Sealing Test Holes
►For double wall (B-vent) flue pipes, letters from vent manufacturers say to use “high temperature, non-hardening sealant to plug the hole on the inner sleeve. Do the same for the outer sleeve, but cover with a patch of aluminum tape over the sealant”.
►For single wall flue pipes, use the same, or metal plugs.
What If A Test Fails?
►If a test fails before air sealing and/or insulating: follow procedure – no air sealing until the problem is fixed
►If a test fails after air sealing and/or insulating: follow procedure – fix the problem
Bonus Video
►6 minute Efficiency Video
What Information is Important?
►Combustion Efficiency 02, Temperature, Fuel
Reduce Fuel Cost - Savings
To determine Operating Condition
Diluting effects of excess air
(NO, NO2, SO2, CO)
Weight of pollutant (lbs/Mbtu)
• Carbon Dioxide (CO2)
• O2 Reference (3%, air free)
• Emission Conversions
• Excess Air Extra Air for Combustion
Courtesy of Bill Spohn, Testo
Typical Readings
►Gas Fired Power BurnersOxygen : 3 % - 6 %
Carbon Dioxide: 8.5 % - 11 %
Stack Temp : 275 ºF to 570 ºF
Draft: -.02WC to -.04WC in the Stack
Carbon Monoxide: <100 ppm (diluted)
Always Follow Mfr‘s Specifications
Courtesy of Bill Spohn, Testo
Typical Readings► Oil Fired Power Burners
Oxygen (cast iron cone): 4% - 7 % Oyygen (flame retention): 3%-6% Carbon Dioxide 10 – 12.5% Stack Temp (60-79 AFUE): 400 ºF to 600 ºF Stack Temp (80 plus AFUE): 330 ºF to 450 ºF Stack Temp (90 plus AFUE): Less than 125ºF Draft: -.02WC Overfire Carbon Monoxide: < 50 ppm (diluted) Always Follow Mfr‘s Specifications
Courtesy of Bill Spohn, Testo