Community Forums

Ikeshel · 06-08-2019, 09:14 PM

The plastic plug on our Class A water heater sprung a leak, fortunately the camp store had a replacement so we had water for our trip.
This is a new (to us 2008) rig. My question id - does the plug HAVE to be plastic and could I replace it with a valve that would allow me to turn a knob to drain it (periodic maintenance to flush the unit and to drain b4 winter)? Or is the plug plastic to act as a "blow out"? (Even though there is a pressure relief on the tank)
Since we are TOTALLY new, I don't want to do anything stupid and hurt my rig.
Thanks in advance

rk911 · 06-08-2019, 09:28 PM

we replaced the plastic plug with a metal plug with a petcock valve on a previous MH. two things to watch for:

- it will be convenient but it will drain SLOWLY. be sure to relieve pressure before draining the tank to speed it up.

- be sure to use a plug either made from nylon or the same metal to avoid problems. i've been told that dissimilar metals can have corrosive effects. we didn't know that at the time but never experienced issues during the 15-years we had the MH.

Old-Biscuit · 06-08-2019, 10:26 PM

Atwood water heater tanks are aluminum...drain hole threads are aluminum
Atwood uses a NYLON plug for couple reasons
*NYLON will NOT strip the aluminum threads...the NYLON will strip first
*NYLON has the proper temp/pressure rating (WH Tank 'could' reach 210*F/150psi...temp/press settings for T&P Relief Valve)

Atwood WH Tank drain hole is only 1/2"
Fittings/hose/valve will result in a smaller drain opening....limiting/restricting draining/flushing especially if scale/crud is present

Atwood NYLON drain plugs come 2 to the service package.
1 to use/1 as spare
they are 1/2" NPT (tapered threads) so install/hand tighten then just snug up
Fill WH Tank and check for leaks...slightly tighten if needed using a 6 point 7/8" socket (Atwood OEM)
Aftermarket sizes could be 15/16" hex head

How difficult is it to use them and remove as necessary?

elite wa · 06-08-2019, 10:40 PM

When our nylon plug stripped out replaced it with a plug with the valve. It’s doesn’t drain fast but to be honest when we park it at the house when we are done I just open the valve and walk away, doesn’t drain any slower then the fresh water tank. The valve I have allows you to keep the base in so you aren’t stripping the water heater threads and the valve is a whole separate piece that you can take out and replace.

speed racer · 06-09-2019, 07:07 AM

Nylon is the recommended material for the plug in the aluminum tank. Don.t make unneeded trouble for yourself. I have a tap to clean up the treads on tanks for people who have done what you want to do. The tank gets build up in the bottom and you have to take the plug out to flush it and with brass or steel plugs with drain cocks this is when the trouble begins.

Gary RVRoamer · 06-09-2019, 10:02 AM

Use a 6-point socket wrench rather than 12-point or pliers and the nylon plugs won't get torn up.

1982 · 06-09-2019, 06:27 PM

Quote:

Originally Posted by elite wa

When our nylon plug stripped out replaced it with a plug with the valve. It’s doesn’t drain fast but to be honest when we park it at the house when we are done I just open the valve and walk away, doesn’t drain any slower then the fresh water tank. The valve I have allows you to keep the base in so you aren’t stripping the water heater threads and the valve is a whole separate piece that you can take out and replace.

I travel in hard-water country. When I tried a valve for a year, I found the flushing action was not enough to get rid of the deposits in the tank bottom. Because this can shorten the tank life, I just went back to the nylon plug and got a socket to fit it for my ratchet.

garry1p · 06-09-2019, 08:37 PM

I think its best to use nylon I tried brass with petcock and different metals caused problems.

elite wa · 06-09-2019, 11:45 PM

Quote:

Originally Posted by 1982

I travel in hard-water country. When I tried a valve for a year, I found the flushing action was not enough to get rid of the deposits in the tank bottom. Because this can shorten the tank life, I just went back to the nylon plug and got a socket to fit it for my ratchet.

We have hard water as well, I just use it mainly for the in between trips to drain the tank. When it comes to winterizing it I take the center plug out.