Check valve on WH

[AFChap]

I'll try to make a long story short and get to the point -- the fancy OEM electric bypass valve on my water heater never did the job. It was replaced twice under warranty before I had the dealer replace it with a manual bypass valve. Several months later I discovered the manual valve wasn't doing the job either! I was headed for the Winnebago rally, so had the factory check the plumbing to find the problem. They stated the check valve on the water heater hot water out line was "not the kind of valve Winnebago installs" and that the fitting was holding the valve open. They replaced it and pronounced it fixed. I haven't winterized since, so assumed it was working properly. Last month I had the water heater replaced. After noting that with the new WH that the hot water did not last as long as it used to, and that it didn't get as hot as it used to, I did some checking and discovered the WH plumbing was backwards -- cold water in was plumbed to the top port and hot out to the bottom. Today I got around to swapping the connections around to get it right. In the process, I removed the line with the check valve in it, and I discovered it was disabled by the fittings too, just like the one Winnebago replaced back in 2006. When assembled and tightened down, the fitting pushed the check valve slightly open.

I finally gave up trying to make it work right. The two check valves look identical on the outside, while one has plastic guts and one has metal guts. I know some owners have totally removed or gutted check valves when they have failed, so I removed the plastic guts and put it all back together with no functional check valve -- but the check valve wasn't really functional anyway!

Now, here's my QUESTION -- what effect might that have on the hot water system other than the bypass valve not working? Can cold water back-flow into the WH and reduce the hot water supply? Am I likely to be heating the whole water supply with no check valve in place? Will it make the hot water colder? ...or the cold water hotter? ...neither to any noticeable extent?

["007"]

Your cold water pressure from incoming water line or from your water pump will keep the cold water in check so flow will be through your water heater. As cold water enters WH it will be heated to temperture set on WH.
Read this thread to understand how to set up bypass valve for winter shut down, may not be your WH but serves same purpose.

[AFChap]

007 ...can you check that link? I get
"Invalid Thread specified. If you followed a valid link, please notify the administrator"

[Harry B]

Same here as to the link not working.

["007"]

Give this thread a try now.

[AFChap]

Good link now. Interesting setup, and would be simple to do on any WH. I like the valves better than my manual bypass. (...guess I could get those valves from a Newmar dealer? ...or perhaps Lowes, etc). The valves on the cold and hot lines add a little "complication" that could confuse some folks, but they would avoid any problem with check valves, etc.

["007"]

The hot and cold water valves will allow complete draining of water heater than shut off RV anti freeze from entering WH, with the bypass valve now open for the anti to bypass the water heater and flow through to your faucet locations.