I have a Peerless hot water oil fired boiler. My problem is that (when I can get it to run) it will get up to temp - give out good heat - shut down like it should - then it will not start up again, even with all three of my zones calling. Once I notice that the boiler is not going to turn on again I turn the thermostats down so they do not call for heat and let the whole system rest idle for a day or two. After that amount of time has passed most times I can turn the thermostat back up and the system will start up and repeat the same process all over again. Sometimes I have to leave the thermostat calling for heat for hous before the boiler will fire up.

The thermostats are electric, are on, show that they are calling for heat, and the reset button on the burner has not tripped. I have replaced the relay box that the thermostats are wired into, the aquastat and a few other things. The circulators are fuctioning fine too. No improvement yet.

My service tech and I are stumped at this point. Does anyone have any ideas?