RV Water Heater Drain Plug Size Guide

The water heater on your RV comes complete with a drain and a drain plug. These are two very important components because you do need to drain that RV water heater sometimes. However, those RV water heater drain plugs need to be replaced on a regular basis. 

They’re usually made of nylon, so they do wear down and require replacement to prevent leaking. That said, you do need to have the right size, which is what we’re here to look at today. Let’s talk about everything you need to know about RV water heater drain plug size. 

RV water heater drain plug sizes

RV Water Heater Drain Plug Size Explained

The simple fact here is that RV drain plugs can come in a variety of sizes, so finding the right one is crucial. If the drain plug in question is too big, it simply won’t fit, and if it’s too small, it won’t properly plug the drain of your RV’s water heater.

Now, there are a few common sizes of RV drain plugs out there. The most common size is 15/16”. However, two other common sizes included 7/8” and 13/16”. However, there are others too.

Some may also be 1/2”/ Therefore, although it is a relatively safe bet that your water heater needs a 15/16” drain plug, it won’t always be the case. It really depends on the water heater model.

Now, after draining the water heater in the RV, some people will use the same old drain plug over and over again. Well, this is not a good idea, as they do wear down over time.

Using the same plug could result in a leak, or worse. Remember that these water heater drain plugs for RVs cost $5 or $6, at the most, so buying a new one should not be an issue. 

Sizes Of Drain Plugs On Common RV Water Heaters;

Seeing as different RVs have different water heaters, let’s take a quick look at the most common RV water heater models and what drain plug sizes they use.

BrandDrain Plug Size
SuburbanDepending on the exact model, this may be a 7/8” or 15/16” drain plug.
DometicAlthough it does depend on the model, these drain plugs often come in a 1/2” size.
AtwoodDepending on the exact model, this may be a 7/8” or 15/16” drain plug.
Forest RiverDepending on the model, this may be a 1/2”, 3/4”, or 15/16” drain plug.
SuburbanThis model of RV water heater will usually always have a 15/16” drain plug.
JaycoThis model of RV water heater will usually always have a 15/16” drain plug.

How To Install/Replace Your RV Water Heater Plug

Let’s go through a quick step-by-step tutorial on how exactly to replace the RV water heater plug. As you are about to see, this is actually quite an easy process.

1. Gather Your Materials

First, you are going to need to gather your materials, which here is going to include the drain plug of choice, a ratchet wrench, a bucket, and some extension tape, up to 10 inches. The first thing that you’ll actually want to do here is to put the bucket under the water heater drain so it doesn’t spill everywhere when you open it up.

2. Remove The Old Plug

The first step in this process is to remove the old water heater drain plug. You need to use the appropriate size of wrench to unscrew it from the drain.

This is a process that you need to perform very quickly because as soon as you take that drain plug out, water is going to start rushing out of the drain. Therefore, that new plug needs to be put in place very quickly.

3. Put In The New Plug

Just take your new RV water heater drain plug and screw it into the opening of the drain with your hand. You can start this process with your hand.

You are now going to use the wrench of choice, the right one for the size of plug you have, and use it to tighten the plug. You absolutely need to use a wrench to tighten it fully so that it cannot come out due to the water pressure.

4. Use Your Extension Tape

Although these plugs are fairly secure, they may leak a little bit from time to time, which is why you are going to want to use about a 10-inch length of extension tape to seal the drain.

Just take a good length of this tape and wrap it around the plug so that there are no areas where water can leak out.

5. Refill Water Into The Heater

A good bit of water probably ran out while you were switching the plug, so you’re going to need to refill the hot water heater. Refill your hot water heater using your method of choice.


What Size Socket Is Needed For An RV Water Heater Anode Rod?

Once again, the exact size of socket wrench you are going to need for your RV water heater anode rod is going to depend on the exact model in question.

For the most part, either a 1” socket or wrench or a 1.5” socket or wrench should do the trick. That said, you do of course need to keep the exact model in mind, so always do some research first. 


You should now know everything there is to know about the size of the drain plug that you need for your RV water heater, as well as exactly how to replace that drain plug with a new one.

Madeline Cooper