Talk of The Villages Florida - View Single Post - Water heater expansion tank
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Old 01-05-2020, 08:11 AM
retiredguy123 retiredguy123 is offline
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Quote:
Originally Posted by bob47 View Post
We live in an older home with no expansion tank. Our water pressure "floats" at whatever the water supply pressure is. If water in the gas water heater expands, it simply expands back into the supply line unless I have closed the main shutoff valve in the garage.

Are newer homes plumbed with a check valve in the water supply line so that water can no longer back up into the main?
I don't think your water system can expand back into the water main, even if you have an older home. If you don't have an expansion tank, the pressure in the water heater can exceed 100 PSI and cause the emergency relief valve on the tank to open and spew out hot water. Or worse, the relief valve can be stuck and fail to open and the water heater can leak or explode. High pressure can also damage your faucets and other plumbing fixtures. I would suggest that you consider installing an expansion tank.