Air Relay breaker

[PJHoffnet]

Electric panel has fwd and aft AC breakers (30A) which obviously go to the two AC units.

Panel also has a 5A breaker labeled - Air Relay. What exactly does that serve/do?

Thanks in advance.

[shrew]

Is there a breaker for AC Pump as well? I suspect there is a breaker for each A/C unit and the breaker for Relay only. You have two AC units and only one AC pump. The relay should allow either unit to call the pump to begin pumping water when the thermostat needs to call for either heat or A/C. On my boat it is labeled as A/C Pump. I suspect its the same thing.

[PJHoffnet]

You've hit it right on the head I think. No, no AC pump breaker. Yes, to separate (2) AC breakers, and the one relay. Probably why it's only 5A and the heavy current draw AC units are 30A.