Rheem is known as a reliable and good-quality brand, providing durable and well-made water heaters at reasonable prices. However, even the best water heaters can have issues, including drain valve ones. Drain valve problems are serious because if they go unsolved, they may cause floods in your basement and do severe damage.
The drain valve of your Rheem water heater might leak because it’s not secured correctly or has deteriorated parts. Additionally, it might be a built-up sediment issue. To fix this problem, you may try securing or replacing the valve, replacing the parts, or even replacing the whole unit.
Stick around if you want to know the step-by-step of each of these solutions. I will also explain in detail why all of these issues can be possible causes for your Rheem water heater drain pipe to leak.

1. The Valve Isn’t Tightened Properly
Sometimes the cause of a leaking drain valve is simply because it has not been tightened properly. While installing the water heater, someone might have forgotten to secure the drain valve well, or someone might have loosened it up by accident.
If the drain valve is not secured correctly, there will be enough space for the water to leak. It might not be noticeable at first because the leak may be slow, but soon enough, you will be able to notice water pooling at the bottom of the heater. The sooner you find the leak, the better.
How To Fix
When the drain valve is not tight enough, the obvious solution would be to tighten the valve. It sounds simple enough, but there are a few steps that you need to follow in order to do it safely and correctly.
- Shut down the water heater and run some water in the sink to make sure the water isn’t too hot.
- Get a bucket or any type of container under the drain valve.
- Open the valve using a screwdriver; if there is any built-up sediment, make sure to remove it.
- Allow water to run out.
- Tighten the valve well using a wrench; don’t apply too much pressure, or you’ll break the valve, causing even more leaking.
- Check to see if the leaking stopped.
2. The Washer Is Damaged
Drain valves have washers in them, which are made of rubber or plastic. Their purpose is to stop the water from leaking out, but sometimes they break or loosen up, especially after a few years of use. As a result, the water starts leaking out.
How To Fix
You can replace a damaged washer with a new one pretty easily. Make sure to buy a new washer like the Baoao Rubber Washer from Amazon.com for replacement.
- Turn off the water heater.
- Remove the handle and the packing nut.
- Get rid of the old washer and put the new one on.
- Put the packing nut and the handle back.
- Test your heater to see if the leak is gone.
3. The Valve Has Deteriorated
Like anything else, valves tend to deteriorate with time. If the valve is made of plastic, it’s especially at risk of deteriorating quickly. The plastic becomes easily breakable after some time passes, which can cause it to be damaged when the valve is used.

The damage that occurs as a result of deterioration can cause leaks. The broken valve provides new ways for the water to leak out. It can help to check the drain valve once in a while, especially if it’s been some time since you bought it. If you can catch it in time, you might be able to fix the situation without any leaks.
How To Fix
If your valve is broken, you have two options: you can temporarily fix it by capping it, or you can replace it as a long-term solution. Both options are relatively easy to do.
To cap a broken valve, you only need a couple of steps and don’t even need to drain the tank. First, you need to get a cap from the nearest hardware store or online, like the American Valve Drain Cap (available on Amazon.com). Remember that it should be the same kind and size as what you would use for your garden hose.
All you need to do is place the cap on the spout and tighten it using a wrench, but you need to be careful not to tighten it excessively because it may cause the drain valve to leak even more. For a longer-lasting solution, get a metal cap.
For a real long-term solution, you should replace the whole drain valve. This is a bit more complicated, but it ensures that your Rheem water heater drain valve will not leak anymore.
You can replace your valve in a few steps:
- Turn off the water heater.
- Connect a hose to the drain valve and open the valve, directing the water to your tub or outside.
- Once you empty the tank, disconnect the hose and close the valve.
- Put towels or other water-absorbing material under the heater and remove the broken valve using a wrench.
- Install the new drain valve using a wrench.
Here’s a video that shows you the whole process in detail:
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4. There Is Sediment Buildup
If you’ve been using your Rheem water heater for a long time, there’s a chance that there are built-up materials inside the tank and, consequently, even inside the drain valve. The sediments can weaken the drain valve and cause it to break, which, in turn, causes water to leak out.
How To Fix
If you believe that this is what is wrong with your Rheem water heater drain valve, you have two options. You can replace your valve, following the steps I showed you above, or you can replace the entire water heater. The latter sounds drastic, but it’s probably the best solution. If there’s sediment around your valve, it comes from the tank itself, which is most likely damaged from the sediment as well.
If you don’t want to replace your water heater, you may try to just replace the valve. However, it’s a temporary solution, and there are chances of water leaking from elsewhere in the heater since the sediment damages the whole tank. If you want to prevent sediment from collecting in your water heater, clean it often.

Summary
There are several reasons your Rheem water heater drain valve might leak. The valve itself might not be secure, or it might be damaged. A part of the valve, like the washer, might be loose or broken. Moreover, there might be built-up sediment in the valve, causing damage from the inside.
The best solution in most of these cases is to replace the valve with a new one, preferably a high-quality, non-plastic drain valve. However, sometimes you might just need to tighten the valve or replace just the damaged part.