Yesterday while running hot water it was very hot --almost boiling. I
have a 40 gal. electric water heater. Does this mean a stuck thermostat
and how do I change it?
Almost boiling, so you mean steam is spitting out, you used a
thermometer and its near 212f, or is it just hot like maybe 140f. If
near 160-212 turn it off at the breaker now, Is the saftey valve
leaking. There are 2 thermostats by turning them you should be able to
feel which one is cutting off at to high a temp, turn both down. If
you have a gas supply now is the time to consider switching as Ng for
me is 60% cheaper. There have been units that the saftey valve froze,
the unit would not stop heating and it went through a ceiling, roof
and landed far away, that is fact. If its old and in fact near 212 I
would junk it as its had alot of extra stress.