Everything was working fine until last night when my Natural gas Burnham Series 2 boiler gave up. Lost heat and hot water. HVAC guy says I need to replace 4 zone valves and thermostats. Asking for $1250. According to him, my White Rodgers zone valve is sending some voltage back which killed the control head on the furnace. Is it a reasonable price for this job? And is it a possible cause?
I wish I knew what you were asking
Sounds like a load of crap to me. A zone valve cannot send voltage out. Unless something is wired totally wrong (unlikely since it was working before), this guy doesn't sound like he knows what he's doing. All 4 zone valves and thermostats are bad? That is a bunch of crap. The relay/transformer on the boiler may be bad, but there is no way what this guy said is right. There is an end switch on the zone valves which turns the pump and boiler on after they are open but usually all the control voltage comes from the same transformer. I find it hard to believe all the zone valves and stats are bad. Get another opinion. It sounds like the transformer may be too small to handle all of the zone valves. And if you have system powered digital thermostats, that just adds to the load. The transformer rating is probably 40 or 50 VA. Look on the zone valve heads to see what the VA rating of each one is. A 40 VA transformer at 24 volts will handle about 2.5-3.5 amps. The 24 volt loads may exceed the transformer rating.
