Check Valve At Hot Water Heater Outlet? I would like HL Braintrust opinions please.

TandT

Founding Utah Chapter Leaders-Retired
Question for my Heartland family,

Recently we have had poor hot water pressure.

Today, I removed the top (outlet) hose at the water heater. There is a small white piece floating in the 1/2" fitting on the water heater. It's not held in place in a housing, just floating in the 1/2" nipple.
It resembles a miniature automotive engine valve, with a small O ring.

I'm assuming this is a check valve, or part of one, to prevent hot side water from being drawn back into the tank when the cold is turned on.
I don't know if this is the way it should look, or has something fallen apart? It seems like it should be held in some way, instead of just floating in there.

Without this plastic piece (valve?) , the pressure seems better.

Is there any serious down side resulting from leaving this piece out, other than maybe getting some warm water back through the cold side?

Thanks in advance, Trace
 
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brianharrison

Well-known member
View attachment brass check valve.bmp

There is a checkvalve on the outlet of the hot water heater to assist in the winterization process. Some have replaced them with brass fittings, where they were plastic.

Without it in place, the winterization process is impossible without having the hot water heater full of plumbing antifreeze.

Backflow into the water heater could occur, probably in scenarios like shutting shower head off at spray nozzle (both taps open) and someone uses another cold water tap......

EDIT: - Link to RV Doctor discussion on hot water check valve

Hope this helps
Brian
 
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TandT

Founding Utah Chapter Leaders-Retired
View attachment 20160

There is a checkvalve on the outlet of the hot water heater to assist in the winterization process. Some have replaced them with brass fittings, where they were plastic.

Without it in place, the winterization process is impossible without having the hot water heater full of plumbing antifreeze.

Backflow into the water heater could occur, probably in scenarios like shutting shower head off at spray nozzle (both taps open) and someone uses another cold water tap......

EDIT: - Link to RV Doctor discussion on hot water check valve

Hope this helps
Brian

Brian, Thanks for the info and the link.

I don't think there was a spring with the piece I found. Otherwise the valve appears to be the same as the one in your picture.
I think I will definitely replace the plastic fitting with brass asap.

The RV Doctor speaks to the hot water heater inlet, but not the outlet.

If winterizing is the only real issue, I think I will just save all the parts.
We fulltime so I don't think I will need to do that in the forseeable future. Trace
 

danemayer

Well-known member
Trace, two of the hazards of the plastic check valve are 1) leaks ranging from annoying to damaging and 2) they can deteriorate and become difficult to remove. If it's still in good condition, I'd recommend you get the brass one and some teflon tape and replace it while it's still a 10 minute job. When you order the valve, take a close look at the gender on each end. Some of the check valves have the wrong gender on one end and you have to also order a close nipple to make it work.
 

Rickhansen

Well-known member
If you replace with a common fitting, I recommend a "swing-check" type valve. It will offer less resistance to flow than the spring loaded type. That, and a close nipple will set you back about $8 at home depot. I originally was going to replace mine with a ball valve, but the swing-check valve was cheaper than a ball valve.
 

brianharrison

Well-known member
The RV Doctor speaks to the hot water heater inlet, but not the outlet.

If winterizing is the only real issue, I think I will just save all the parts.

I like the RV Doctor in how he answers his questions clearly, for the general lay person however some of this answers are slightly off base, in my opinion. I have seen check valves on the outlet AND inlet of hot water heaters; outlet for winterization and backflow prevention, and inlet for secondary backflow prevention and to protect sediments from backflowing from the Hot water heater (scale from hot water heating (think tea kettle scale), and anode rod droppings......). Most installs do not use both these days, and typically only outlet.

Your spring is probably in your hot water heater. No big deal, and you will probably find it if you flush out your hot water heater every once and a while (recommended).

Hope this helps.
 

JJOren

Well-known member
We had the same check valve on the water heater in the Landmark. It was plastic, it has already failed and leaked. It was replaced with Brass and a galvanized nipple. Definitely a better arrangement!!!!
 

TandT

Founding Utah Chapter Leaders-Retired
Thanks, guys. I am going to pull that outlet nipple out tomorrow and head to Ace hardware for a brass fitting. (My inlet valve is brass)

I also like the swing type check valve idea. It sounds less restrictive.

I should have said this flow problem got worse after I changed my anode rod and all that scale got loose in the tank.
I tried to flush it, but the pressure still became worse.

I'm going to check my cold into the tank fitting as well. It may have gotten scale in it. Trace
 

DougAndJudy

Well-known member
Be aware that the plastic check valve may not come out cleanly. Sometimes it breaks when you try to remove it, leaving the plastic threads stuck in the water heater. When this happened to me, I bought a 1/2" npt thread tap to clean the plastic out of the water heater.
 

gasman

Camp Socializer
When that plastic thread broke off on mine, I heated it up with a heat gun and used a sprinkler system nipple extractor. The piece came right out.
 

TandT

Founding Utah Chapter Leaders-Retired
Trace, two of the hazards of the plastic check valve are 1) leaks ranging from annoying to damaging and 2) they can deteriorate and become difficult to remove. If it's still in good condition, I'd recommend you get the brass one and some teflon tape and replace it while it's still a 10 minute job. When you order the valve, take a close look at the gender on each end. Some of the check valves have the wrong gender on one end and you have to also order a close nipple to make it work.

Dan,
I removed the check valve at the top of the hot water heater and replaced it with a BRASS 1/2" nipple. Water is flowing better with no problems so far. I now have brass fittings both in and out of the water heater.

I noticed in the plastic one I took out, the rest of my check valve piston and spring was in there, as Brian said.

I also noticed the fitting has a ridge to hold the spring in place. Due to this ridge, the opening is reduced to maybe 3/8", thus restricting flow in itself.

Thanks for the info and I will post any negative symptoms from not having this check valve, if they occur. Trace
 
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