Plumbing in the Home/Hot water heater


Would you happen to know if a hot water heater can release carbon monoxide when no hot water is being used?

Leah, With natural gas and propane fired water heaters,carbon monoxide is a by-product of combustion. If the heater vent(chimney) is defective, disconnected, rotten or has holes in it, then when the burner is running it will release carbon monoxide will leak into the  house and it is odorless and deadly if prolonged exposure.
Also, if the chimney going outside  is plugged for any reason, the same thing will occur. A good way to check the chimney is to light a match and hold it close to the draft diverter and see if it pulls the flame then extinguish the flame and see if the smoke is drawn up as well. One other thing, if the draft diverter,the little bonnet that sits directly on the heater and has the silver colored pipe attached to it, has hot air coming out of it when the burner is running then you have a chimney problem. Turn it off and call a plumber or you gas supplier.Lastly, your water heater will run wether or not you are using water. It has to maintain temperature 24/7 and heat radiates out of it constantly therefore, it will run to keep up and be ready for use. At no time should carbon monoxide be present or allowed to escape the chimney/vent system.


Plumbing in the Home

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Jay Nicholas


Plumbing & Heating (warm air, hot water & steam heat)


40 years in the business, 40 years as a lic. master plumber in NY State. Retired

Graduated Magna cum laude at the School of Hard Knocks

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Commercial, residential and light industrial. You name it ...I have probably worked on it

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