D.6 Appliance-Specific Inspections

The following appliance-specific inspections are to be performed as part of a complete inspection. These inspections are performed either with the appliance in the off or standby mode (indicated by "OFF") or on an appliance that is operating (indicated by "ON"). The CO measurements are to be undertaken only after the appliance is determined to be properly venting. The CO detector should be capable of calculating CO emissions in ppm air free.

1. Forced Air Furnaces:
   1. OFF. Verify that an air filter is installed and that it is not excessively blocked with dust.
   2. OFF. Inspect visible portions of the furnace combustion chamber for cracks, ruptures, holes, and corrosion. A heat exchanger leakage test should be conducted.
   3. ON. Verify both the limit control and the fan control are operating properly. Limit control operation can be checked by blocking the circulating air inlet or temporarily disconnecting the electrical supply to the blower motor and determining that the limit control acts to shut off the main burner gas.
   4. ON. Verify that the blower compartment door is properly installed and can be properly re-secured if opened. Verify that the blower compartment door safety switch operates properly.
   5. ON. Check for flame disturbance before and after blower comes on which can indicate heat exchanger leaks.
   6. ON. Measure the CO in the vent after 5 minutes of main burner operation. The CO should not exceed threshold in Table D.6.
2. Boilers:
   1. OFF and ON. Inspect for evidence of water leaks around boiler and connected piping.
   2. ON. Verify that the water pumps are in operating condition. Test low water cutoffs, automatic feed controls, pressure and temperature limit controls, and relief valves in accordance with the manufacturer's recommendations to determine that they are in operating condition.
   3. ON. Measure the CO in the vent after 5 minutes of main burner operation. The CO should not exceed threshold in Table D.6.
3. Water Heaters:
   1. OFF. Verify that the pressure-temperature relief valve is in operating condition. Water in the heater should be at operating temperature.
   2. OFF. Verify that inspection covers, glass, and gaskets are intact and in place on a flammable vapor ignition resistant (FVIR) type water heater.
   3. ON. Verify that the thermostat is set in accordance with the manufacturer's operating instructions and measure the water temperature at the closest tub or sink to verify that it is no greater than l20°F.
   4. OFF. Where required by the local building code in earthquake prone locations, inspect that the water heater is secured to the wall studs in two locations (high and low) using appropriate metal strapping and bolts.
   5. ON. Measure the CO in the vent after 5 minutes of main burner operation. The CO should not exceed threshold in Table D.6.
4. Cooking Appliances
   1. OFF. Inspect oven cavity and range-top exhaust vent for blockage with aluminum foil or other materials.
   2. OFF. Inspect cook top to verify that it is free from a build-up of grease.
   3. ON. Measure the CO above each burner and at the oven exhaust vents after 5 minutes of burner operation. The CO should not exceed threshold in Table D.6.
5. Vented Room Heaters
   1. OFF. For built-in room heaters and wall furnaces, inspect that the burner compartment is free of lint and debris.
   2. OFF. Inspect that furnishings and combustible building components are not blocking the heater.
   3. ON. Measure the CO in the vent after 5 minutes of main burner operation. The CO should not exceed threshold in Table D.6.
6. Vent-Free (unvented) Heaters
   1. OFF. Verify that the heater input is a maximum of 40,000 Btu input, but not more than 10,000 Btu where installed in a bedroom, and 6,000 Btu where installed in a bathroom.
   2. OFF. Inspect the ceramic logs provided with gas log type vent free heaters that they are properly located and aligned.
   3. OFF. Inspect the heater that it is free of excess lint build-up and debris.
   4. OFF. Verify that the oxygen depletion safety shutoff system has not been altered or bypassed.
   5. ON. Verify that the main burner shuts down within 3 minutes by extinguishing the pilot light. The test is meant to simulate the operation of the oxygen depletion system (ODS).
   6. ON. Measure the CO after 5 minutes of main burner operation. The CO should not exceed threshold in Table D.6.
7. Gas Log Sets and Gas Fireplaces
   1. OFF. For gas logs installed in wood burning fireplaces equipped with a damper, verify that the fireplace damper is in a fixed open position.
   2. ON. Measure the CO in the firebox (log sets installed in wood burning fireplaces or in the vent (gas fireplace) after 5 minutes of main burner operation. The CO should not exceed threshold in TableD.6.
8. Gas Clothes Dryer
   1. OFF. Where installed in a closet, verify that a source of make-up air is provided and inspect that any make-up air openings, louvers, and ducts are free of blockage.
   2. OFF. Inspect for excess amounts of lint around the dryer and on dryer components. Inspect that there is a lint trap properly installed and it does not have holes or tears. Verify that it is in a clean condition.
   3. OFF. Inspect visible portions of the exhaust duct and connections for loose fittings and connections, blockage, and signs of corrosion. Verify that the duct termination is not blocked and that it terminates in an outdoor location. Verify that only approved metal vent ducting material is installed (plastic and vinyl materials are not approved for gas dryers).
   4. ON. Verify mechanical components including drum and blower are operating properly.
   5. ON. Operate the clothes dryer and verify that exhaust system is intact and exhaust is exiting the termination.
   6. ON. Measure the CO at the exhaust duct or termination after 5 minutes of main burner operation. The CO should not exceed threshold in Table D.6.

TABLE D.6
CO THRESHOLDS

Central Furnace (all categories)	400 ppm1 air free2, 3
Floor Furnace	400 ppm air free
Gravity Furnace	400 ppm air free
Wall Furnace (BIV)	200 ppm air free
Wall Furnace (Direct Vent)	400 ppm air free
Vented Room Heater	200 ppm air free
Vent-Free Room Heater	200 ppm air free
Water Heater	200 ppm air free
Oven/Boiler	225 ppm as measured
Top Burner	25 ppm as measured (per burner)
Clothes Dryer	400 ppm air free
Refrigerator	25 ppm as measured
Gas Log (gas fireplace)	25 ppm as measured in vent
Gas Log (installed in wood burning fireplace)	400 ppm air free in firebox

1. Parts per million
2. Air free emission levels are based on a mathematical equation (involving carbon monoxide and oxygen or carbon dioxide readings) to convert an actual diluted flue gas carbon monoxide testing sample to an undiluted air free flue gas carbon monoxide level utilized in the appliance certification standards. For natural gas or propane, using as-measured CO ppm and O₂ percentage:
   
   
   

   Where:
   COAFppm	=	Carbon monoxide, air-free ppm
   COppm	=	As-measured combustion gas carbon monoxide ppm
   O2	=	Percentage of oxygen in combustion gas, as a percentage

3. An alternate method of calculating the CO air free when access to an oxygen meter is not available:
   
   
   

   Where:
   UCO2	=	Ultimate concentration of carbon dioxide for the fuel being burned in percent for natural gas (12.2 percent) and propane(14.0 percent)
   CO2	=	Measured concentration of carbon dioxide in combustion products in percent
   CO	=	Measured concentration of carbon monoxide in combustion products in percent