Where is HW tank one way check valve?

beardedone

Beardedone
I am embarking on a plumbing upgrade and installing residential style manifolds and straightening out the plumbing overall. What I need to know is where the one way valve out of the hot water tank is. Is it inside the tank. I wanted to disconnect the poly pipe at the tank itself and run a line from there to my manifold. Don't want to screw something up. thanks.
 

JohnDar

Prolifically Gabby Member
It should be the white or black plastic fitting coming out of the hot water outlet port on the tank. They've been known to fail or break, so several folks have replaced them with brass ones. I have one in my "kit" for that contingency (or when I get off my duff to replace it).
 

SouthernNights

Past South Carolina Chapter Leader
Gerry,
It is on the outlet side of the tank as John pointed out. That is the TOP line on the back of the tank.

There is a good chance it could snap off when you try to remove it. Pipe dope on plastic works very well. If it does you can carefully take a pick and break off the threads inside the port.
 

boatto5er

Founding VA Chap Ldr (Ret)
Gerry,
It is on the outlet side of the tank as John pointed out. That is the TOP line on the back of the tank.

There is a good chance it could snap off when you try to remove it. Pipe dope on plastic works very well. If it does you can carefully take a pick and break off the threads inside the port.


I seem to recall a certain "Southern Gentleman" having to do this at Cape Hatteras!
 

RollingHome

Well-known member
Gerry excuse me for butting in, guys, I checked on the search bar... no luck, what are you guys talking about ? Why do our units have a check valve on the water heater... I'm having one of those Duh, moments. Can somebody bring me up to speed ? In advance thanks. Tom
 

JohnDar

Prolifically Gabby Member
It's a back-flow preventer. I assume the purpose is to prevent water from draining back into the water heater from the hot water lines once the demand is gone, allowing the tank to refill with fresh, cold water via the bottom. That's my non-plumber's crack guess, anyways.
 

SouthernNights

Past South Carolina Chapter Leader
Gerry excuse me for butting in, guys, I checked on the search bar... no luck, what are you guys talking about ? Why do our units have a check valve on the water heater... I'm having one of those Duh, moments. Can somebody bring me up to speed ? In advance thanks. Tom


Without it you can not bypass the water heater.

When you switch the bypass valve to "bypass" you are still pressurizing the hot water lines. it does it through a "T" after the water heater. Because of that, with out the check valve you would still be letting water into the water heater, only it would enter through the "out" side. That would defeat the purpose of bypassing the water heater.
 

RollingHome

Well-known member
Thanks guys, guess I have to draw it out... I'm a visual guy and cannot visualize want's going on without drawings.... my shortcomming.... Oh well.
 

katkens

Founding Illinios Chapter Leader-retired
Thanks guys, guess I have to draw it out... I'm a visual guy and cannot visualize want's going on without drawings.... my shortcomming.... Oh well.[/QUOTE

I agree with Larry's answer above. I have an '07 Bighorn ,which doesn't have the new winterizing system located in the UDC . I have to manually turn valves behind the water heater to winterize, mine doesn't have a check valve at the water heater connection.....Kenny
 

katkens

Founding Illinios Chapter Leader-retired
Thanks for all the replies. Sometimes simple is better isn't it Ken.

I like simple and really not hard taking a few screws out to winterize. It also gives me the chance to check water connections for leaks and make sure everything is tight. I have found that due to all the vibration from traveling down the road one can find a connection that needs a little snugging up at years end. I can at least say I have never had a leak one in 4 years , well gotta go and find a piece of wood to knock on....Kenny
 

SouthernNights

Past South Carolina Chapter Leader
Maybe this will help Tom.

Look at the hose marked "Cold water" at the bottom of the picture. You will se a "t" in it. This "T" feeds the bypass valve with cold water (or campground) water.
In the normal mode, all the water does is go up to the valve and is redirected to the water heater inlet side. This is the lower hose on the back of the water heater. Even though I have replumbed my basement, this is all original from the factory.
When you place the valve in bypass mode the water is diverted through the hose marked "BYpass mode"
You can see that hose runs directly to the hot water manifold. This is the way you can supply water to the hot water faucets even in bypass mode. All it does is eliminates the water going to the heater.

As you can see, without the check valve, or as Ken uses a gate valve or ball valve, you could not eliminate water going to the water heater. Without the check valve or gate valve, water would try to enter the water heater through the outlet side canceling the "bypass mode"
The check valve position is marked on the top of the water heater.

(After you open up the picture , click on the picture to maginify it so you can see better. I am not the sharpest tool in the shed when it comes to computers, this was the best I could do.)

034..jpg
 

RollingHome

Well-known member
Thanks Larry, the pic helped a lot :) My unit is still new and I have not even had the panel off yet, it's on the to do list. The dealer had it off when it came in from HL to check for leaks etc. I peaked in but with the maze of pipes, cables and wires it was a blivit. Now I understand 'why' the check valve is there. Prior I only knew a WH by-pass to be 3 manually operated valves. Your pic also enables me to to see things that were discused on the forum, like pump location, cabled dump valves, etc. By the way, the hot link John Dar posted on the forum the other day was useful in understanding those critters, I don't know if you had time to view it or not, well worth the time. Thanks again, Tom
 
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