You may be worried if your gas water heater is backdrafting. Backdrafting happens when some of the toxic gas is released into your home and not outside. This situation may be scary for you but you should take action immediately to keep your home and your family safe.
Common ways to test for backdrafting are to look for melted metal, corrosion or moister around the top of the water tank, excessive condensation, vent connector problems, insufficient air intake, and improper installation. Ways to stop backdrafting are to clean the air filter, reconnect the vents, and clean your chimney.
Backdrafting may be a scary situation but you can easily check for and fix backdrafting. Remember to not panic and to keep yourself safe at all times. Let’s look at the proper ways to test and fix the backdraft.
Why Does a Gas Water Heater Backdraft?
Your gas water heater is backdrafting because it is most likely an atmospheric venting gas water heater. This type of water heater is made so that the gases may be released from the chimney. These gases are also designed to rise when released. As they rise through the chimney, they exit your home which keeps you safe.
Backdrafting is occurring because it could be installed incorrectly. If there is an improper installation then the gas can’t exit. For example, if the vent pipe has an angle downward or has too many angles that don’t allow for gases to rise.
There could be a blockage in your vents. If there is a blockage then the vent will fill up with air and eventually fill into your home. It is possible that there is a build-up of dust or potentially something from the outside that got stuck in the vent.
Now we are going to look at how to test for back drafting. If you are comfortable enough, you can do all of the tests yourself. These tests are an easy and effective way to test for back drafting. Most of the tests involve looking or checking for something. You will not have to use a lot of tools when you check.
How Can You Test For Backdrafting?
The easiest ways to identify backdrafts are by looking for melted metal, corrosion, and moisture. If you have more experience, you can identify vent connector problems or improper installation.
Look For Melted Metal Around the Draft Hood
Melted metal around the draft hood means that your water heater is backdrafting. The draft hood is located on top of the water heater. It is connected to the ventilation system and the water heater. The draft hood should have openings underneath so that there is proper airflow.
If there is melted metal around the draft hood then the draft hood cannot properly ventilate out. Your draft hood can also be plastic which is easier to melt. Sometimes people think that it could have been melted from the welding process of putting the water heater together. However, this is unlikely to happen and you should call a professional to repair the draft hood.
Corrosion Around the Top of the Water Tank
Signs of backdraft due to corrosion are that you see dried-up white-ish stains. These stains will be all over the top of the water tank. You want to get a clear look at the top of the water tank. You should take a step stool or a small ladder to get your head above the water tank. Use a flashlight so that you can see it properly.
Corrosion can be caused by two things. The first is that there is a leaking shut-off valve which does not have to do with backdrafting. The second is from the water tank being old. Corrosive condensate will build up over time causing backdraft.
Moisture Around the Top of the Water Tank
When you see moisture around the top of the water tank you are first-hand witnessing the process of back-drafting. If there is moisture, there will also likely be rust or signs of corrosion. To check for moisture you should get your head above the water tank and use a flashlight to see.
To check for moisture you can also take a paper towel or rag and wipe the top. However, if you do not want to touch the water tank then the rust is enough to let you know there is a problem. You should get away from the tank, as there are toxic gases being released close to you.
Excessive Condensation on the Cold Water Pipes
Condensation on your cold water pipes can be normal. In hotter months such as summer, there may be a little condensation build-up. However, if you are noticing excessive condensation then this is a sign of backdrafting. You should be able to see the build-up or you can wipe the pipe with a paper towel.
The cold water pipes are connected to the wall and your water tank. To make it easier you should look at the part of the pipe connected to the wall. Move anything that is blocking it out of the way and check to see if there is excessive condensation. Water may be dripping off which is a sure sign of backdrafting.
Vent Connector Problems
Your vent connectors may be angled incorrectly. If there is a sharp turn just after the draft hood it is likely this is causing backdrafting. The gas needs to rise and a sideways vent will not allow for that. Sharp angles after the beginning of the vent will also cause the gases to not rise properly.
Vent connector problems are caused by the amount of space you have during the installation process. If they were installed in a tight space that required vents to be angled then this could be the root of the problem.
Insufficient Air Intake
To function properly a gas water heater needs the majority of the air in the room. The metrics for a water heater are 50 cubic feet of air per 1,000 BTUs/hr. Meaning your water heater should be taking in a good amount of air.
Air intake is needed so that the water tank can heat up. You can check if there is enough air by doing a draft test. Just cup your hands around the draft hood and you should feel warm moist air.
Look For an Improper Installation
Check for proper water heater installation for an atmospheric venting gas water heater. It should look like a water tank and the vent going straight up through the ceiling and out. Since the gas needs to rise, there should not be angles or turns in the vents.
Once you check for and determine that your water tank is backdrafting you will want to stop it. There are numerous ways that you can stop backdrafting. Some may be harder than others, but there is a solution to the issue.
How To Stop Your Gas Water Heater From Backdrafting?
The best way to stop backdrafting is by disconnecting and reconnecting your vents. If that is not possible for you start by cleaning your air filter or clean the chimney using a vacuum or call a chimney cleaning company.
Clean Your Air Filter
To clean your air filter turn off the power to the furnace. Find the filter which may be behind a panel. If it is then use a screwdriver to open the panel and access the filter. Take the filter out and rinse the filter down with a hose until the filter is clear. Let it dry in the sun until there is no water left. Then put the filter back.
Some water heaters have a filter with a cardboard frame. If you pull out the filter and see a cardboard frame then you should replace the filter. The ones with cardboard frames cannot be washed.
Reconnect Your Vents
To reconnect vents you start by turning off the gas supply and unplugging the electricity. Turn the valve that lets water into the tank perpendicular to shut it off. Empty the water tank with a pump. You then have to disconnect the vents by cutting the vent in the proper spot.
Once you have disconnected the vents you can reconnect new ones that are angled properly or that are clean. To do this you may have to use welding tools or pipe adaptors to connect them together again.
Clean Your Chimney
To clean the chimney you will need a vacuum. You want to first start by turning off the gas and electricity to the water heater. For extra safety wear a mask and goggles to protect yourself from the dust. Then open and remove the vent hood.
Once you get the vent hood open, turn on your vacuum and vacuum around the front and as far down as you can. Try to use or get a vacuum extension that allows you to reach far into the vent. This way you can get any unexpected debris
So… Should You Be Worried About Your Gas Water Heater Backdrafting?
You should be worried about your gas water heater backdrafting. You do not need to panic though. Follow this article on how to check for backdrafting. If you find any issues then take proper steps to stop them.
Take safety precautions when around exposed gas. If you do not feel comfortable being around toxic gases then call a professional for help. They will be able to assess the issue and fix the backdrafting for you. Although you may want a professional to help you, it is important to know how to check for and stop backdrafting so you can quickly take action.
Backdrafting can be alarming when you first discover it but there are easy ways to check and fix the issue at hand. If you suspect that the fix requires repairs, the best way to ensure your water heater does not backdraft again is by replacing the vents or the whole water tank.
Ruben has a diverse background in the home services industry, with experience running a construction company, a kitchen and bath showroom, and a moving and relocation company. This breadth of experience has provided him with a wealth of knowledge and expertise in various areas of home improvement in general and specifically in the heating and plumbing niche.