Hot water not flowing at any faucet

[Skidaver]

I removed the old check valve and three pieces fell out, a white plastic poppet, an o-ring and a spring. There must have been a retainer and possibly a guide for the poppet that was no longer there. I reinstalled the empty housing and now have hot water flowing again. Access wasn't easy, so I elected to order a new valve as shown in the attached picture, versus a shutoff valve. I want to thank all of you who responded with advice, particularly Old-Biscuit and vettenuts. Your advice was spot-on.

[vettenuts]

Glad you got it fixed. Curious if you could get both hand in there or had to remove and install with only one hand?

[Skidaver]

I was able to get both hands in there. On my 2011 40QTH, the water heater is in the rear closet. There is a wood panel above it, about 2' x 2', held in place with four screws. After I removed that panel, it was easy. I just had to move a large bundle of wires out of the way. The breakers and fuses are on the front side of that same cabinet.

[NorCal Hal]

The GREAT thing about Tiffin is they are still in business, and they have VERY helpful customer service people. I don't understand why people write to a forum and wait days for other people's opinion when they can call the manufacturer and get expert's answers. (256) 356-8661