Rheem RTGH-RH11DV with built in recirculation : what is the fitting type for the recirculation port?

Users who are viewing this thread

Mike89

New Member
Messages
16
Reaction score
0
Points
1
Location
London, On
I have had this water heater for 4 years now, no real issues (aside from water temp fluctuations when someone turn on a hot water tap when I am in the shower). I suspect this is typical for natural gas gas tankless water heaters, please comment if it is not.

My current issue is the unit came with a built-in recirculation pump, and while I had the plumber run a dedicated 1/2 inch return line, I have yet to connect it. In my last attempt I found out the return line port on the Rheem unit was NOT 3/4" NPT (in this case not 3/4" MPT). I tried attaching a 3/4" FPT to it and it leaked like a sieve, even with copious amounts of teflon tape..

It looks like 3/4" straight thread, which to me is similar to a garden hose end, and would need a rubber gasket to create the seal? Does this sound right? Can anyone recommend a fitting? Ideally I would like a 3/4" straight thread gasketted to 1/2" pex a expansion pipe adapter, but I woul'be be greedy :) Anything to get me away for this weird thread to a normal NPT thread would work.

I feel like the gasket will have a finite life in a hot water loop, but I don't see many other choices here.
 

Fitter30

Well-Known Member
Messages
4,340
Reaction score
791
Points
113
Location
Peace valley missouri
If the 3/4 screwed on to by hand its nps has the same number of threads 14 as npt and will use a gasket. A box store, Ace hardware might have the fitting plumbing supply that carries Rheem heaters. If the gasket is epdm there would be no problem with temp.
 
Last edited:

Tuttles Revenge

In the Trades
Messages
4,175
Reaction score
1,439
Points
113
Only thing I can think they would have straight threads is for a filter port. No way Rheem would make a pressure connection without tapered threads. At least on purpose.
 

Mike89

New Member
Messages
16
Reaction score
0
Points
1
Location
London, On
Here is a close up picture. Posted in case the cap type is a clue, ignore the extra thick teflon tape, will probably be fully removed if I can confirm it is a straight thread.

1703363846859.png
 
Top
Hey, wait a minute.

This is awkward, but...

It looks like you're using an ad blocker. We get it, but (1) terrylove.com can't live without ads, and (2) ad blockers can cause issues with videos and comments. If you'd like to support the site, please allow ads.

If any particular ad is your REASON for blocking ads, please let us know. We might be able to do something about it. Thanks.
I've Disabled AdBlock    No Thanks