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Topic: Check Valve / 'weekend plumber' (Read 330 times) previous topic - next topic
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Check Valve / 'weekend plumber'
Dear All,

Recently I had to replace something called a "check valve," which--I believe--connects the fresh water supply to the line through which the pump draws water from the supply tank and sends it along to the various fixtures. (Photo attached.) The old was spurting water out everywhere, in all kinds of directions, like in the movie Edward Scissorhands, what he does to the waterbed. Anyhow I'm very happy to report that the new one, which I ordered from the very outfit that manufactured the original (in case you're interested, Hydronamic Engineering Corporation in Brea CA) is NOT doing THAT. But it is letting fall, ever so slowly, at the rate of about one drop a minute, well, drops of water.

I plan to take it off and reinstall it (this time, I hope, properly). My question is: any tips how not to foul it up this second time? It is a Brass check valve, 1/2" MPT x 1/2" FPT, 1psi, Buna.

Sincerely,
All Thumbs

Sean
2001 26' Mid Bath
Re: Check Valve / 'weekend plumber'
Reply #1 –
Hi Sean;  That new check valve should have white Teflon tape on both the input and outlet pipe threads. I can see it on one end (left side) of the valve but not quite visible on the other (outlet) end. Is that where it is leaking?  This check valve prevents hot water from the water heater (the white insulated object this is attached to) from migrating back into the cold water supply line.  So this fitting is on the cold water line coming from the pump, before it goes to the water heater.     This picture of a similar valve from e-Trailer, shows the arrow (flow) going to the water heater.  https://www.etrailer.com/RV-Fresh-Water/JR-Products/37262195.html?feed=npn&utm_source=google&utm_medium=cpc&utm_campaign=Google%20%7C%20Shop%20-%20RV%20Fresh%20Water&adgroupid=92836574544&campaignid=925016149&creative=404001549035&device=c&devicemodel=&feeditemid=&keyword=&loc_interest_ms=&loc_physical_ms=9031352&matchtype=&network=g&placement=&position=&gclid=CjwKCAjwg-GjBhBnEiwAMUvNWzMNTRNYLNxX-ELEqwzVPf94UeqeNpCd30NG_eV5lJEyR5Da7l7WEhoCyGYQAvD_BwE     RonB
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB
Re: Check Valve / 'weekend plumber'
Reply #2 –
Yes that’s where it is leaking. I will try that! Thank you!!

(I did try it originally, but it was damn hard to get on, there’s no room for manœuvre down there for a klutz like me.

I don’t suppose there’s a substitute for Teflon tape you cd smear all over the other end?

Thanks again! (Thanks too for describing the function and location of the thing!)
Sean
2001 26' Mid Bath
Re: Check Valve / 'weekend plumber'
Reply #3 –
Yes,

T Plus 2 in. 4 oz. Teflon Pipe-Thread Putty/Sealant, available at most big box lumber yards.

Once used teflon tape should be replaced.  If you take apart both ends re-do both ends.
Theresa & Everett  GLLDCC Making wonderful friends at LD rallies.
Surfside our 2018 31IB ( our current LD)   Sandcastle  2001 26.5MB ( our first LD)
Michigan born and home based. Traveling with our spoiled dog Dax.
Re: Check Valve / 'weekend plumber'
Reply #4 –
Perfect. Will do! Thanks again!!
Sean
2001 26' Mid Bath
Re: Check Valve / 'weekend plumber'
Reply #5 –
Hi Sean.  The thread lube needs to be on the threads you can't get to. So you will need to take it apart again (sigh!)  You can use thread compound, but you already have the Teflon tape, and it isn't as messy.  The 'union' turning part is on the far left, so you'll need to replace that tape also.
    Now before you do that, loosen the far left fitting a bit; support that elbow with a wrench, and tighten the valve where it goes onto the elbow fitting.  Then re-tighten the far left ferrule nut and check for leaks again. You might get lucky.  But of course, no brass fitting is perfect, and the Teflon tape is there to fill in minor imperfections.  RonB
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB
Re: Check Valve / 'weekend plumber'
Reply #6 –
Your probably a 1/4 turn from success. Like Ron said loosen the union end some and see if you can tighten just a little more.
When I have problems, I use a generous amount of teflon tape then a light coating of teflon based pipe dope mostly for lubrication when your screwing together. If you have to completely take it apart, clean everything up and start over. Make sure you use a good backup wrench on that 90 degree fitting out of the water heater. The very worst thing that could happen is if that fitting broke off in the tank.

Jon
 
1994 MB
Re: Check Valve / 'weekend plumber'
Reply #7 –
All thumbs,
Mine is a 1988 MB. I hesitate to post as mine is the inaugural year. and things change rapidly.  and I have the old 460 Ford engine.
Access can be improved by disassembling the right twin bed.  Remove the cushions, remove the single slide bar guide(wood) by removing the screws from inside. The bar (1 x2 wood) may drop into the outside storage compartment. Mine was NOT glued to the slide. move the slide portion aside.  Remove the screws holding on the cover over the Hot Water Heater.
I was very aggravated at the check valve and what the issues it caused in filling the Hot Water Heater with air for expansion, and pump cycling.  I also have a swamp cooler. and assumed the check valve was to keep hot water out of the swamp cooler.  I removed the check valve.  I replaced it with an expansion tank and 3 feet of pex between the expansion tank and cold inlet.  The expansion tank is mounted inside the Mr. & MRS Wardrobe Drawer compartment on the rear wall closest to the Hot Water heater. I have made a post about the water pipe path previously and will add later.
Water leak in floor
Rodney
1988 Mid Bath
Re: Check Valve / 'weekend plumber'
Reply #8 –
Thanks everyone for all your input. I decided to start over (took it apart again and reattached, this time using a combo of teflon tape and pipe-thread gunk) and...it appears to have worked!

RodneyHelfrich, mine is a 2001 and all this business is behind the electrical panel and under the sink. (BTW the fix you devised for your problems--hugely impressive!!--is many miles above my pay-grade.)

Very grateful to this wonderful community---

best,
Sean
Sean
2001 26' Mid Bath