Vent for Gas Hot Water HeaterIs a water heater vent an important part of your home. Yes, for more than one reason. Your gas hot water heater needs air to operate. Once the gas is burned the fumes need somewhere to go.

Not sure if this is your problem? See the article on 'How To Troubleshoot Gas Water Heater Problems' for a complete listing of issues and the resources to solve the problems.

The first thing to check would be the 'Draft on the Water Heater Vent'. The next major concern would be 'blockages', 'Blocked Water Heater Vents' and 'Blocked Chimney Flues' cover these issues. Read below for an overview on this subject.

Poor venting can cause your water heater to burn inefficiently. It can also be dangerous, since the burner produces carbon monoxide. What are the problems? Can you fix them yourself? You can learn to solve this problem yourself.

Local building departments have differing requirements for venting a hot water heater and they should be consulted when questions arise. In general the vent pipe that comes up from the hood on the water heater should never be reduced.

water-heater-vent-pic1You should have as much vertical rise as possible before there is a turn. The vent pipe has to run up hill a minimum of a quarter of an inch per foot. The fume hood needs to be seated properly on the top of the tank. This article deals with water heater vent, repair issues.

Repairing a Water Heater Vent Using Common Sense

What Can You Save? - Checking and cleaning your vent will run you between $75 and $125. There is not much to it. A repairman should have a meter that checks the draft. Other than that it is pretty simple. Having your chimney cleaned could run another $75 to $200. Chimney cleaning is needed if there is an obstruction.

How Hard Could It Be? - Cleaning and checking a water heater vent is not that hard. These repairs will have a Difficulty Level of: Simple. These repairs require a Skill Level of: Handyman

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What Can Go Wrong? - There is a serious danger that can arise from an improperly vented water tank. Carbon monoxide can be deadly. Make sure you have a working carbon monoxide sensor in your home. Shut the hot water tank down if you suspect the vent is blocked. Clear away the obstruction first. Shutting the hot water tank down could be a big inconvenience.

Troubleshooting Gas Water Heater Vents

How can I check to see if the vent is working?

The first thing you want to know is if your vent is working or not. The article 'Checking the Draft' covered this topic, providing a simple test to see if your vent is drawing properly.

How can I tell if there is a blockage in my flue vent?

A blocked or partially block vent can cause dangerous fumes to build up inside the house. This problem needs to be corrected immediately. See the article on 'Removing Blockages From Vent Pipes' for instructions on what to do.

The vent is clear, but there is still no draft, what is the problem?


Similar to a blocked vent, a blockage in your chimney flue can be dangerous. However, clearing a blockage from the chimney is difficult and requires special tools. See the article 'Clearing a Blocked Chimney Flue' for instructions on what to do.


So what did you get into? Did you check the draft? You may have had to do some work on your fume hood. They get banged around a little over time. Did you have an obstruction? Were you able to clear it out yourself? Hopefully you have been able to solve your problem. Calling a service to clean out your chimney is an expense, but well worth it.

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