If the hot water was just used (before closing valves) then
the water in the tank is cold. Water expands as it's heated.
The expansion will force a few drops of water out the TP
valve.

--
Christopher A. Young
Learn more about Jesus
www.lds.org
..


"fftt" wrote in message
...
Possibly damaging the T&P valve. It's a safety valve not
meant to open over and over again. When the valves are
popped open more than a few times, they will tend to start
leaking. Besides, if the valve doesn't go outside or to a
drain, you will wind up with a very wet floor to mop.

TDD

Why is the T/P valve going to open?

It will only open (when both inlet & outlet valves are
closed) IF the
water heater over heats due to a failed thermostat.

T/P valves only open when T or P exceeds limits.......

cheers
Bob