wrong pressure relief valve...???

GoodoleBob · 09-02-2021, 02:38 PM

I'm disappointed in myself. A few months ago I had issues with my original Water Heater Pressure relief valve. I bought a new one. It was labeled as a numeric replacement for the one that was original to my Sunline. The RV parts guy said should be just fine.

Fast forward to today...got half way through the replacement to the point of screwing in the new one...and it is no where near the proper fit for my HW heater...was to small a thread. I can push it in all the way and wobble it...that how bad the misfit is.

So I will go back to the RV dealer with both part and see what's up. Now I want to know in case the dealer has nothing suitable. Is this type part simply part of the plumbing world such that I could buy one at Lowe's for example? Or where is another reliable place to try in case the dealer fails me again. Thank.

Bob

Tinstaafl · 09-02-2021, 04:09 PM

A box store might or might not have what you need. I'd take the original to a plumbing supply house. Those guys are much more knowledgeable about all aspects of plumbing than most RV dealer/box store staff.

**JohnB** · 09-04-2021, 06:36 PM

Hi Bob,

I know what happened.

Somewhere is about later 2005 to early 2006, the Atwood heaters changed the relief valve from a 1/2" NPT port in the tank to a 3/4 NPT port in the tank. I know many of the 2007 model year Sunlines built in 2006 had the 3/4" NPT port.

This is the last 3/4" one I put in a 2007 Sunline. Watts 3/4" Lead Free Temperature and Pressure Relief Valve, LF100XL-DP-TT-150 https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

As fyi, here is the older 1/2 NPT one. Atwood 91604 It is also a Watts brand.
https://www.amazon.com/Atwood-91604-...802037&sr=8-14

Hope this helps

John

Also the temperature sensing probe length needs to be close too. Not just the screw in port hole if you are going to the big box store to get one.

GoodoleBob · 09-06-2021, 08:07 AM

Hi John...yes that's the truth in my situation. Fortunately the same dealer did have the exact Watt's component I needed and I was able to install it just fine. Must say that brass into aluminum is a very tight fit. Yes I did wrap Teflon tape as part of the assembly. Thanks again John.

Bob