Should I put a back flow preventer or check valve on the water inlet on a
water heater ?

"Ed" wrote in message
. net...
Should I put a back flow preventer or check valve on the water inlet on a
water heater ?

Thats about the last thing you want to do. Why would you even consider it?

"Ed" wrote in message
. net...
Should I put a back flow preventer or check valve on the water inlet on a
water heater ?

That depends. A house that I owned up until 6 years ago was on top of a
hill. When the water supply failed (e.g. when there was a fire on my
circuit and the pumpers went whole hog) the water from the tank got sucked
back into the mains and the heating elements on my heater burned out ...
happened several times ... I was forced to install a check valve.

"Charles Schuler" wrote in message
. ..

"Ed" wrote in message
. net...
Should I put a back flow preventer or check valve on the water inlet on a
water heater ?

That depends. A house that I owned up until 6 years ago was on top of a
hill. When the water supply failed (e.g. when there was a fire on my
circuit and the pumpers went whole hog) the water from the tank got sucked
back into the mains and the heating elements on my heater burned out ...
happened several times ... I was forced to install a check valve.
I am tempted to say that is impossible. Even if a siphon could be
established, if no taps are open the water in the heater couldn't get sucked
out.

"Ed" wrote in message
. net...
Should I put a back flow preventer or check valve on the water inlet on a
water heater ?



As the others have asked, why? Siphoning the water tank dry sounds pretty
unlikely if all taps are closed.

But anyhow, your water meter may already have one as I believe most newer
meters are required to have them (5-10 years). If your heater has an
expansion tank hanging from the ceiling on the hot side, then you already
have one.

Toller wrote:
Thats about the last thing you want to do. Why would you even consider it?

There are (at least) 2 possible reasons for a check valve on the inlet
of a hot water heater.

1 - Some municipalities require a check valve to prevent the flow of
water from the house back to main.

2 - A check valve is used when a recurculating system is used to
prevent long waits for hot water at fixtures far from the heater.

If you do use a check valve, you should also use an expansion tank in
between the valve and the water heater. If you don't, you run the risk
of having water leak from your pressure relief valve when the water
heats up and has no place to go due to the check valve.

Toller wrote:
Thats about the last thing you want to do. Why would you even consider it?

"Ed" wrote in message
. net...
Should I put a back flow preventer or check valve on the water inlet on a
water heater ?

Toller wrote:
- I am tempted to say that is impossible. Even if a siphon could be
- established, if no taps are open the water in the heater couldn't get
sucked
- out.

I'd like to agree, but this thread seems to indicate that its possible:

http://www.askmehelpdesk.com/plumbin...-dry-9164.html

Read the last response in the thread.


"Charles Schuler" wrote in message
. ..

"Ed" wrote in message
. net...
Should I put a back flow preventer or check valve on the water inlet on a
water heater ?

That depends. A house that I owned up until 6 years ago was on top of a
hill. When the water supply failed (e.g. when there was a fire on my
circuit and the pumpers went whole hog) the water from the tank got sucked
back into the mains and the heating elements on my heater burned out ...
happened several times ... I was forced to install a check valve.
I am tempted to say that is impossible. Even if a siphon could be
established, if no taps are open the water in the heater couldn't get sucked
out.

My water comes from my artesian well.
I am concerned about losing heated water flowing back towards the well tank.


Thanks

Ed

not in buffalo ny, but if required by your local plumbing codes.

Ed wrote:
Should I put a back flow preventer or check valve on the water inlet on a
water heater ?

Ed wrote:
Should I put a back flow preventer or check valve on the water inlet on a
water heater ?

In most cases, no. but some towns are now requireing backflow preventors in
every home. They are needed with in-ground sprinkler systems.

buffalobill wrote:
not in buffalo ny, but if required by your local plumbing codes.

Ed wrote:
Should I put a back flow preventer or check valve on the water inlet on a
water heater ?

If it is required by code, it will be required at the house supply
inlet, usually where the service enters the house (unless it is part of
the meter). It won't specify that it is neededon the water heater.
Someone else pointed this out but I will add it again. If a check
valve is placed on the heater inlet, then an expansion tank should be
installed.

Harry K

replying to Toller, Mike wrote:
Its called a vacuum breaker bud. Lets air into the tank to prevent it
from imploding in backflow conditions.

--
for full context, visit https://www.homeownershub.com/mainte...er-178433-.htm

On Friday, June 1, 2018 at 11:14:12 PM UTC-5, Mike wrote:
replying to Toller, Mike wrote:
Its called a vacuum breaker bud. Lets air into the tank to prevent it
from imploding in backflow conditions.
--

You're too late. 10 years ago, Toller was abducted by aliens from Outerspace. The Air Force was unable to catch up with the flying saucer and bring it down. Toller was never seen or heard from again. It's feared that the aliens used him as a sex slave before eating him. It was such a tragic loss. o_O

[8~{} Uncle Sad Monster

replying to Ed, Hunter wrote:
If your cold water comes into the water heater from the bottom, as it does in
a mobile home, the water will definitely siphon out causing your elements to
burn out.

--
for full context, visit https://www.homeownershub.com/mainte...er-178433-.htm

replying to Hunter, Rudy wrote:
The solution is to install a syphon breaker valve. Run the supply line up
above the top of the tank and place the syphon breaker there. Tee off just
below the syphon breaker and run pipe to the water heater inlet.
If there is any syphon on the water line, the valve will open and let air in,
breaking the syphon. Because the valve is above the tank, the water in the
tank is trapped. This is code where I am.
If you use a check valve, it has to be a two way check valve with a relief
port to allow expansion to escape back into the water line when the water is
heated.

--
for full context, visit https://www.homeownershub.com/mainte...er-178433-.htm