No Hot Water Pressure

[MarathonMike]

Hello,
I have owned my 32 foot 2003 5th Wheel Cardinal for 3 years and live in it 6 months at a time. I just opened it up for the season and can not get hot water pressure. I have city water access as well as a full fresh water tank. Neither source gives me hot water.

I have a Suburban hot water tank. I have flushed the hot water tank and the mineral rod is long and in good shape. I have cleaned the screen near the water pump.

My cold water flows strong with the the pump on or if using city water.
All the cold faucets and cold shower run strong. The hot water doesn’t have good pressure on any of the outlets. The hot water starts off strong for a couple seconds and then dwindles down to a trickle. This is the case wether on city water or using the pump.

There is a switch on the back of the hot water tank that I believe bypasses the hot water tank. When I flip it one way I get a strong water flow through the hot water faucet options on all the outlets, except it is cold water. So makes me think it is just a bypass.

Is there a check valve somewhere that could be stuck, and where would that be?
Is there a screen I am missing somewhere that could be clogged?

Thanks for any suggestions.

[rockfordroo]

There are a number of ways they plumb the WH bypass. See the attached and figure out which one you have.

Note that only Options 4a and 4b utilize one valve to make the swap between normal and bypass. The others all use either 2 valves or 3 valves.

Good luck.

[MarathonMike]

Originally Posted by rockfordroo

There are a number of ways they plumb the WH bypass. See the attached and figure out which one you have.

Note that only Options 4a and 4b utilize one valve to make the swap between normal and bypass. The others all use either 2 valves or 3 valves.

Good luck.

Thanks for the diagram. Looks like I have 4a like the photo in the lower right hand corner....it mentions Hot Outlet Check Valve but I can not identify that. All I see with the hot water lines is T’s where I would think the Check Valve may be.

I used my phone camera to look around the side of the heater and I don’t see anything obviously a check valve there either.

Do you have any guidance here?
I have attached a photo of my heater’s backside.

[rockfordroo]

The check valve is the brass fitting coming out where it says HOT.

I THINK your valve is in the Bypass position in the pic, but it's not always clear where the handle should be; but you should try it both ways.

If you still have a problem, it may be the check valve isn't opening, or some other issue.

(Have you verified the WH is full? Open the T&P relief valve and make sure you have water coming out. If no water comes out, turn the valve the other way and try again.)

[Villagerjjm]

I think you have a chunk of something that is blocking either the water supply to the water heater tank or the hot water line out of the tank.

[MarathonMike]

Originally Posted by rockfordroo

The check valve is the brass fitting coming out where it says HOT.

I THINK your valve is in the Bypass position in the pic, but it's not always clear where the handle should be; but you should try it both ways.

If you still have a problem, it may be the check valve isn't opening, or some other issue.

(Have you verified the WH is full? Open the T&P relief valve and make sure you have water coming out. If no water comes out, turn the valve the other way and try again.)

Awesome, thanks for identifying that for me. I’ll replace it tomorrow when I head to the big city and hopefully that will solve the problem.
I have verified the tank is full by waiting until it comes out of the overflow valve before shutting off. And I tried the valve both ways a number of times.
Thanks!

[CHICKDOE]

you say you have good water flow out of the hot water faucets when you bypass the water heater. close all the how water faucets, turn the valve on the cold water line from the bypass position to the water heater position, and open the pressure relief valve. does a good flow of water come out the pressure relief valve? if so, the valve on the cold water line is allowing cold water into the tank. if not, the valve on the cold water line may be defective or not in the proper position to allow water into the tank.

if you are getting a good flow of water into the tank but not at the hot water faucets the check valve is either stuck closed or it is clogged with the white sediment from the tank. take if off and clean or replace.