Hello,

I have a Crown oil boiler and Crown megastor 40 gallon indirect water
heater. The system has 3 zone valves but a single circulator (water
heater is on zone 2).

Today we had only lukewarm water coming from the faucets. The zone
valve for this zone is open, the boiler is working and there is pipe
from the boiler to the water heater is hot. But the pipe coming from
the water heater returning to the boiler does not get hot.

The other two zones are getting heat so the circulator seems to be
working properly.

This problem has happened several times in the past few weeks and it
seems to start working again for a while.

Has anyone had this type of problem? I appreciate any advice that you
can offer to me.

Thank you in advance,

Scott