Water Heater Exhaust is Spilling

Problem: The water heater is combusting properly, but some gases are not getting into the flue pipe and out of conditioned space either due to an issue related to air pressure or improperly sized or installed exhaust. This may be due to not enough makeup combustion air in the room.

Possible Solution: Install a transfer grille, if fixed hold up mirror to the exhaust air supply when the water heater is running. If it fogs up after running for 60 seconds, the problem remains. If not, the unit is no longer spilling.

Poor Draft in Flue Pipe

Problem: A poorly vented flue pipe is most likely due to a poor installation or damage over time. As a rule, the flue should always proceed upwards until out of the house, and a vented cap is to be placed at the top to prevent obstruction.

Possible Solution: Clear any obstruction in the pipe, ensure most direct vertical path to get exhaust out of house


At Worst Case Because of the Dryer

Problem: Often, a water heater is placed next to the dryer in a utility room. Dryers pull air from the room and exhaust it outside along with lint and heat. Because of the proximity, this pulls the exhaust gases from the water heater into the room, preventing proper exhaust.

Possible Solution: Install makeup air in the form of a high-low pipe to the attic or a transfer grill in the door. Makeup air must be large enough to mitigate problem, depending on how badly the CAZ fails.

At Worst Case for Another Reason

Problem: Conditions in the living space are such that one or multiple appliances that move air, such as the air handler or exhaust fans, are causing negative pressure to pull exhaust gases back into the house. This is more common with powerful range hood fans and unbalanced or duct systems with large amounts of leakage. The worst case is also achieved by closing certain interior doors, further unbalancing the system.

Possible Solution: If possible, rebalance the system and seal ducts if this is the problem area. If there is no vent in the CAZ, close it off from conditioned space by air sealing the door to the room. This can possibly be solved through the EE Upgrade process depending on conditions.

Contact: Work can proceed, but will be tested after work to make certain problem is been solved.

Water Heater Burns Dirty

Problem: If the exhaust gas is burning too dirty, in which incomplete combustion of natural gas results in carbon monoxide, rather than carbon dioxide, being produced the unit must be serviced by a plumber who is certified to operate on that particular brand. Most often the problem is fixed by cleaning the burning element. The flame from a clean water heater should be blue, not yellow.

Possible Solution: Get the appliance serviced by an appropriate contractor in the area

Contact: A&E Factory Service, 1-800-905-9505




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