David Starr wrote:



Thanks to all for the help. I'll have to look into an expansion tank.


If space is tight, there are some "tall skinny" expansion tanks which
became available in the past few years. They can slip into the space
between a round tank shell and the walls of a corner it's siting in.

To put some dimension on the expansion of heated water, raising the
temperature from 50F to 180F will increase its volume by about 3%, which
equates to over a gallon of extra volume for the amount of water in your
40 gallon tank.

Jeff

--
Jeffry Wisnia

(W1BSV + Brass Rat '57 EE)

"As long as there are final exams, there will be prayer in public
schools"