Have HVAC Questions? Ask an HVAC Expert for Answers
Hi I am dan I can help you with this. The priority means that if the tank zone calls for heat then it will turn off the heating zones until the tank is satisfied. Are you having problems with the domestic water heating up or the boiler water?
When the heat is calling is the temp fine? Is it just a problem when the heat is off? How old is the tank?
ok was the aquastat changed after the problem or did the problem start after the aquastat was replaced. Also what is the model number of the aquastat.
ok what is the model of the aquastat and the zone pannel?
ok the next thing i would look at is the zone panel. first thing i would try is switching the tank wires to one of the other zones and see if that helps the problem or if you get a problem with the zone you switch to the priority zone
no i relize it will take some time to test that out. just reply back when you can. what we are testing is the zone board may be bad or maybey intermitent where is does not always bring the boiler on when the water heater calls but turns on the circulator