Leaking/Cracked Hot Water Check Valve Nipple

[TheNescios]

Steve, was looking at having to do something similar but jumped on the forum and did a search figuring this topic had come up at some point - the pipe nipple extractor set below was $8.99 at Harbor Freight and was absolutely effortless on how it removed the broken nipple with zero thread damage.
Brian, agree with your thought process, but will be at least removing and inspecting the nipple when I do the anode - much prefer a planned water shutdown and replacement of parts vs an unplanned outage with repairs while my 4 yr old granddaughter was here.

[howson]

The kit at Harbor Freight referenced in this thread is here: https://www.harborfreight.com/5-piec...set-93822.html

Gonna pick me up a set next time I'm at the store. Yoda -- I know you'll be getting a set, too.

[Yoda]

The kit at Harbor Freight referenced in this thread is here: https://www.harborfreight.com/5-piec...set-93822.html

Gonna pick me up a set next time I'm at the store. Yoda -- I know you'll be getting a set, too.

Those do look interesting - But for now I will stick to my wood chisel set. I find one the just fits the inside tight and put a crescent wrench on the square shaft they have. But I will admit those look like a lost better way to go.

[Jlawles2]

We always used the larger more course ones when I was growing up. https://www.amazon.com/Neiko-01925A-...s%2C148&sr=8-5

[Yoda]

In an effort to keep this short I will post this as an alert....
This post is for my 2017 Solitude 310GK. About a week ago I noticed some carpet segments I had laid in the basement were wet. And a day and two days later they were more wet.... drenched. I pulled everything out, opened up the access panel, and immediately saw that water had been leaking for some time in this area. Edges of the floor covering had peeled up and the plywood underlay had turned black.
Fortuntely the wood was wet and had not softened, but will still need some preventive maintenance.
When I looked over at the mass of spaghetti behind Nautilus panel I wondered how I would ever tind the leaking joint. For some reason I looked up at the water tank and saw that drips of water were coming off of the hot water outlet check valve nipple, steadily dripping faster than a drop each second
I twisted the fittings a bit to see if an o-ring or something like that was not sealing properly. A couple times there was a steam of water and I could see this was pretty serious. I shut down the water, drained the system, and disconnected the tube fitting end.
When I took a wrench and tried to twist the nipple out of the hot water heater the nipple broke off, leaving the threaded in inside the hot water heater. Holy cow!!
I made calls to Suburban/Airexcel customer service and found an RV dealer close to me was an approved service center. I could take the RV to them and leave it for 5-6 weeks for repair, take the heater out and take it to them, etc. Well, am living in the RV full time right now so also tried a mobile RV repair guy I knew. In the end I found I had a qualified plumber living in the RV park I am in and he spent several hours cleaning out the plastic threads.
Since then we have been trying -- without success to this point -- completing the repair. There are several problems found in all of this, so far....
1. I had a leak fixed at a GD dealer last summer. I thought the repair was made properly. When i first saw the leaking nipple before breaking it off, someone had "smeared" plumber's putty around the base of the nipple. When I looked at the fracture surface of the part after I broke it I could see there was a crack in the nipple where the leaking had come from. There was NO WAY the plumber's putty was going to fix this.... n so it just kept leaking for the past 5 months.
2. When the nipple was originally installed there was some kind of cement used to seal the nipple in the hot water heater.
3. The Suburban service center sold me a brass replacement nipple/check valve. Great... and much better! Except....
4. The male thread on the nipple is a 1/2 NPT thread. After cleaning out the female thread on the hot water heater we discovered it is an M20 thread.
5. I spent all day today running to the GD dealer, plumbing supply stores, and Lowe's trying to find a solution. The only parts the GD dealer had was the old plastic nipple with the 1/2 threads. I can only conclude that when the RV was assembled the 1/2 thread nipple was basically jammed into the m20 thread. It CAN be done.
If that nipple had fractured completely, which over time it surely would have done, water would have blasted out of the hot water heater into the basement. It would have been a disaster. If I had any idea of what materials had been used, and how they had been used, I would have replaced the nipple/check valve LONG ago.
After the weekend I will contact Suburban CS in Tennessee for help. In the meantime I am 4 days with no running water..... RVing CAN be fun!!

I am not sure how you determined you have M20 threads on the tank - should be 1/2 npt. If they really are M20, this fitting should solve your problem https://www.threadtoolsupply.com/alu...m20-12npt.html
https://internationalconfig.com/icc6.asp?item=01614
https://www.galco.com/m20-1-2-mencom.html
Trying to help
Keith

On edit I added a few others. There are more out there too in various materuals.