RV Hot Water Tank Plug Size (Dometic, Atwood)

Even small parts need to have the correct replacement size or you can end up in ‘hot water’. This fact goes for water heater drain plugs as the fit has to be exact or they will not stop any water from leaking out. The problem is the different brands may make different sizes.

The difference between brands may be minuscule but the difference is very important. Suburban drain plug size is 15/16ths of an inch while the other brands may only be 3/4 inch for thread size. Make sure to have the brand name and model number with you when you search for a drain plug.

To learn more about this important small part, just continue reading our article. It explores the issue so you can find the right size for your RV or travel trailer without too much hassle.

What Size Socket For an RV Hot Water Heater?


The standard size everyone has been mentioning is a 1 1/16 inch socket. This is the socket size which should not be confused with the thread size. There will be a little difference between the two.

Also, you will need to have a 6 point or 6 sided socket and not the standard 12 point model. The latter design is often credited with rounding the head of the plug making it impossible to remove later on.

You can use a crescent or adjustable wrench instead of a socket if there is room. These two socket alternatives may be old school but they are very effective in removing bolts, plugs, and other similar pieces of hardware.

The only drawback to those two tools is that they need enough space to move, whereas with a socket you can always add an extension to get to the needed room. Either way, the drain plug should come off fairly easily since they are made from nylon now and should not get stuck due to rust or corrosion.

Drain Plug on Dometic Water Heater


These are plastic or nylon these days. What that construction material is telling you is that you have to be careful when tightening or loosening the plugs. They can ruin fairly easily if too much pressure is applied.

If you could find one with metal threads that would be better as the metal would last a lot longer as well. The thread size for the Dometic option is 1/2” making it a lot smaller than the Suburban model.

The cost of this plug will depend on where you buy it. One outlet has two for $10.51 and another outlet has it on sale for $5.65 for two down from a regular price of $8.01. It may be better to shop for a generic plug instead of paying those high prices for a small plastic part.

Since these are made from plastic, you should not use a 12-point socket on them. Stick with a 6-point model or go with the crescent or adjustable wrench alternatives. You do not want to ruin the plugs before they get to do their job.

Also, do not forget to add Teflon tape to the threads. You want to make sure the water does not find its way out of your water tank, even slowly.

What Size is The Drain Plug on an Atwood RV Water Heater?


This is probably going to be the same size as a Dometic drain plug as Dometic owns Atwood and runs the company. The thread size is going to be 3/4 the same as Dometic and that will require a socket size of 7/8”.

If you need a socket size of 1 1/16” then your water heater is probably a Suburban and not an Atwood. Camco makes drain plugs for RV water heaters. They make them to fit both Atwood (Dometic) and SUburban so you can get the 7/8 or the 15/16” size from that company.

Not sure if that option is cheaper or not but you can always look for a metal drain plug in the same size at your local plumbing supply outlets. The key to this replacement task will be the anode rod.

It is said that you should replace it long before it gets to 0 diameter. Some people replace it every year. The anode rod protects the metal inside your water heater so you need to make sure it is in top condition.

Where To Find a Drain Plug

This is not going to be that time-consuming or difficult. Amazon has a fairly good selection of drain plugs that should work for your model of the RV water heater. If Amazon doesn’t have the one you want, then all the big box outlets should.

They should have the room to carry a few different brands in stock. The big issue will be the price and normally, you just can’t buy 1 in a pack. If you do not like shopping in the big box stores, there are plenty of places like camping world, RV parts nation and so on that will have these parts on their shelves.

When all else fails, you should be able to find some top-quality parts at hardware and plumbing stores across the nation. Those last outlets may have the drain plugs made out of metal. Which is always better than plastic any day of the week.

Some Final Words

Replacing a drain plug is a DIY project that anyone can do. It only takes a few minutes to remove, check out and replace. The key will be to have your brand and model number on hand when you search for a new replacement plug.

Those pieces of information will make it easy for you to find the right part at the right price. Just make sure to pick up a couple of extra when they are on sale to save big the next time you need to replace the plug.

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