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Old 02-01-2022, 07:49 AM
retiredguy123 retiredguy123 is online now
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Quote:
Originally Posted by mamamia54 View Post
Our water heater does not have an expansion tank. What does an expansion do and are they really necessary?
Yes, the expansion tank is necessary. It is required by the building code, but some older houses do not have them because the code was not in effect at that time. And, some plumbers will replace an old water heater and neglect to add the expansion tank. The expansion tank provides an air cushion in your water system to maintain a safe water pressure. When the tank heats up, the water expands a little and, without an expansion tank, the pressure can get too high, especially if all of your plumbing fixtures are turned off. The expansion tank should contain half water and half air, so the water can expand into the expansion tank and the pressure does not increase. The pressure in the expansion tank is normally set at about 60 psi. The expansion tank protects both the water heater and all of the plumbing fixtures in your house from damage due to excessive water pressure. When replacing your water heater, it is a good idea to require the plumber to include an expansion tank in their price quote.