I live in a mobile home park any they are shutting off the water to work in the lines. It is siphoning my tank and causing my elements to burn up. Why is this happening and how do I keep it from happening again?

Your cold water supply to the house should have a check valve in it. Either yours has failed or you do not have one.

The only way it could happen is if you have a leaking hot water faucet. There is normally a "hole" in the cold water line, inside the tank, to break the siphon as soon as the water level drops, does your cold water go into the bottom of the tank? Either install a vacuum relief valve on the tank's cold water line, (the best solution), or install a check valve and hope it seals completely.

Many mobile home WH's are cold fed at the bottom of the tank.

I don't know about "many" but I have only seen a few like that.

Thank you. My tank is fed from the bottom. How would I know if the cold line has a hole when it's inside the tank? I don't know what a check valve is. Also I don't have any leaking faucets but what if there is a leak where I can't see or get to it?



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The "hole" is only on heaters that have the cold water into the top. A bottom feed tank needs a check valve, which any plumber can obtain and install. he can also determine WHY the negative pressure in the tank did not keep the water in the tank.

Thank you...I'll look into it today...appreciate the input.



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a check valve on the cold side of a water heater will mean an expansion tank must be added.
simpler to bring the cold 6 inches higher than the tank and install a tee with a watts N36 vacuum breaker.

packy is absolutely correct


for the OP:

loop the incoming cold water above the tank, install a vacuum breaker at the top of said loop, then drop down and connect to inlet of tank

watts water heater vacuum breaker (install on top of supply loop, NOT on heater)




the vacuum breaker will 'open' to admit air to break the siphon if or when the cold water supply pipe 'back siphons'

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"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638



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bernabeu, even a stopped clock is correct twice a day..
my code mandates that the cold pipe rise to 6 inches above the heater. at that point they want a vacuum relief and the cold water shut off.

once a day if a 24hr clock

==============================================

"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638