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Author:
Robranger714 (TX)
They keep turning off the water to my trailer park at least once a week to fix broken pipes. When this happens, I ALWAYS have to replace the water heater element. Its a single element 3800W water heater. Now I THINK this is maybe because my top fed water heater is somehow siphoning back into the main water line when this happens and the element burns out.. I cannot always be home to turn off the breaker when they shut off the water.Last time, I went ahead and replaced the thermostat as well. And it happened AGAIN.This even happened when no one turned on any hot water faucets in the house.
I googled until my eyes bled and best I can think of is I may need a device to prevent the backwards siphoning of the tank during these water shut offs.There are no leaks to any of the supply lines in the house.
Any help is appreciated.
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Author:
hj (AZ)
The water should not siphon out of the tank unless a hot water faucet is open or leaking, but a check valve on the cold water line should stop it, but then you also need a "hot water expansion tank" between it and the heater to prevent excessive pressure build up when the heater operates.
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Author:
Robranger714 (TX)
The issue is the tank is draining when they shut off the neighborhood supply, not my shut off valve at my house. Someone told me that my tank may be siphoning back into the main supply due to vacuum pull coming from the street lines.
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Author:
hj (AZ)
Water can ONLY siphon out of the tank IF air is allowed to enter it through the hot water piping on the outlet of the heater. If that does not happen the "vacuum" will keep the water in the tank until something is opened to "break" the vacuum.
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Author:
bernabeu (SC)
hj,
? perhaps his heater has a vacuum breaker ?
OP,
check valve (on cold supply) + expansion tank (after check) = problem solved
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"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638
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Author:
packy (MA)
a watts N36 installed in a tee in the cold water inlet to the tank will stop this.
no check valve nor expansion tank will be needed.
N36 vacuum breaker is a required valve in the state of mass...
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Author:
Wheelchair (IL)
You can turn your water main OFF, when you leave and upon return, turn it back ON. That would be the least costly and the most effective. Installing a check valve will cost you, plus the fact that you will have to install an expansion tank. Your community should consider posting a "water repair" sign when working on pipes so that as you pass out and in, you will know that pipes were worked on that day.
Best Wishes
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Author:
hj (AZ)
That should be on the cold inlet which would PREVENT siphonage under any condition.
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Author:
hj (AZ)
quote; you will know that pipes were worked on that day.
By that time any damage would already have been done.
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Author:
bernabeu (SC)
OP,
Follow packy's advice re: Watts vacuum breaker on inlet side
Packy,
DOH
picture me hitting the side of my head
HARD
==============================================
"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638
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