thermal expansion
thermal expansion
(OP)
gentlemen, small time old town, big time problem. town installed new water meters with check valves in all houses. Houses without expansion tanks are experiencing pipe failures. Exactly how much water is displaced (pushed backwards} in piping without check valves during a normal heating cycle of a hot water heater. Will someone please punch the numbers and have an easy answer that borough councle members can understand. Here is the info I can give you. supply line 3/4 id house line 1/2id copper normal system pressure is 60 psi. supply water temperature varies from summer to winter. do not take temperature/pressure relief valves on water heaters in to consideration. I really think someone is going to put ther water tank into orbit sooner or later. thanks, Richard





RE: thermal expansion
TTFN
RE: thermal expansion
v water at 60C is 1.017089 cc/g
that's a 1 1/2% volumetric change
If you use 40 gallons for a bath, and the water heater heats 60F water up to 140F, the expansion is 0.6 gallons.
If you don't let it expand, according to table 6.1.8 of page 6-10 of Mark's Handbook the thermal expansion coefficient of water would be 4.26 x 10-5/psi. It will raise the pressure in the system by up to 358 psi.
You should be popping the safety valves on water heaters in the houses without expansion tanks.
RE: thermal expansion
If the latter, I would think we could calculate a pressure increase per temperature for increase based on ratio of temperature-density coefficient and pressure-density coefficient.
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RE: thermal expansion
RE: thermal expansion