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Water heater fill issue-valve issue?

rmnpcolorado
Explorer
Explorer
Looking for ideas...after we de-winterized, it seems like our water heater will not fill without having the bypass valve open. I'm suspecting that I have a valve that is not turning (even though the knob turns), as the water heater is heating fine. Thoughts??

Stupid question: does the hot water come out the top or bottom of the heater? I would think its the bottom but my plumbing doesn't seem to concur.
2020 Ford F-150 3.5L w/Max Tow
2023 Riverside RV Intrepid 240BHi
8 REPLIES 8

rmnpcolorado
Explorer
Explorer
This was exactly what it was. I was able to remove the cold water intake valve and replace it, and now everything works as it should!
2020 Ford F-150 3.5L w/Max Tow
2023 Riverside RV Intrepid 240BHi

ADK_Camper
Explorer
Explorer
I had the same problem with my hot water heater. In my case it was the top valve (at the hot output). The solution was to cut out and replace the defective valve. You might be able to do the work yourself. Shark bite connectors are easy to work with and require no special tools. Just make sure you have clear access to do the work; some systems can have real cramped access.

Old-Biscuit
Explorer III
Explorer III
You have 3 valves/...........


Bottom...cold inlet OPEN
Middle ......Bypass (connects cold water line to hot water line) CLOSED
Top......hot outlet OPEN

Cold inlet (bottom valve) is NOT allowing water into WH tank. Need to replace that valve

You have water in WH tank because you had bypass valve OPEN and HOT outlet valve OPEN with water supply on. With a hot outlet valve there is no check valve to prevent backflow

You have water flow thru faucet hotside IF bypass valve is open because it comes from cold water system thu bypass to hot water system...but just cold water cause it bypasses WH Tank

Replace cold inlet valve

Is it time for your medication or mine?


2007 DODGE 3500 QC SRW 5.9L CTD In-Bed 'quiet gen'
2007 HitchHiker II 32.5 UKTG 2000W Xantex Inverter
US NAVY------USS Decatur DDG31

rbpru
Explorer II
Explorer II
I flush The antifreeze with the bypass open and the input and output closed. Then open the input and output valves and close the bypass. Next open the nearest hot water faucet, start the pump or turn on the city water. Let the air blast out of the hot water line until the water heater fills and water flows out of the faucet.

Turn on the remainder of the hot faucets to blow the air out. Turn on the water heater. Works for me.
Twenty six foot 2010 Dutchmen Lite pulled with a 2011 EcoBoost F-150 4x4.

Just right for Grandpa, Grandma and the dog.

westend
Explorer
Explorer
rmnpcolorado wrote:
If I want water to flow I have to have the bypass valve open. Even with the hot and cold valves open, I get no flow. Nothing from faucets, nada.

The hot top/cold bottom concurs with plumbing. So the hot would be "exhaust" if you will. Which tells me my intake valve is remaining shut when I turn the knob.

I just hate to rip it apart, be wrong and then have to put it back together. 🙂
Have you tried more than one faucet set?
You can experimentally check that the valve to the cold water input of your heater is working or not by turning off the water heating elements, turn the bypass to off, and open the water heater drain valve. The water will continue to drain with pressure behind it and the pump will run if there is flow into the tank. If the drain stops flowing, then the supply valve to the water heater or a check valve would be suspect.
'03 F-250 4x4 CC
'71 Starcraft Wanderstar -- The Cowboy/Hilton

DutchmenSport
Explorer
Explorer
Sounds like you have only 1 valve on your system. Here's a photo mine showing hot on the top and cold on the bottom.



This position the valve is in, in the photo, is ... bypass off... meaning, water is filling in the tank.

To bypass on ... the valve handle would be facing up. A check-valve in the Out-hot line keeps the water from back feeding into the tank when the system is bypass "on".

There again, don't know if your's has 1 valve, 2, or 3, but if only one, that's how it works.

rmnpcolorado
Explorer
Explorer
If I want water to flow I have to have the bypass valve open. Even with the hot and cold valves open, I get no flow. Nothing from faucets, nada.

The hot top/cold bottom concurs with plumbing. So the hot would be "exhaust" if you will. Which tells me my intake valve is remaining shut when I turn the knob.

I just hate to rip it apart, be wrong and then have to put it back together. 🙂
2020 Ford F-150 3.5L w/Max Tow
2023 Riverside RV Intrepid 240BHi

westend
Explorer
Explorer
Your water would have to flow into the heater for it to heat the water. Maybe, the hot water supply lines were vapor locked when you initially tried to fill it. Did you open a faucet valve in order to get the air out of the hot water system?

What happens to the hot water when you close the bypass valve?

Typically, most water heaters have the outgoing water on the top of the heater and the cold supply enters the bottom.
'03 F-250 4x4 CC
'71 Starcraft Wanderstar -- The Cowboy/Hilton