How do you wire two 24v thermostats in two different zones that will run one 110v circulating pump?
Thanks

If you system was properly installed each zone has a solenoid on the hot water manifold. One stat goes to one solenoid and the other stat to the remaining solenoid.

In a zone system, the thermostat has 2 jobs, fire up the boiler and open the zone valve. The circulating pump should be wired to the circuit that fires up the boiler. In some systems, then the valve opens, it makes a circuit to fire the boiler. Check the sticky at the top of the heating forum for more details.

Each thermostat should control a zone valve, when the valve opens an end switch closes turning on the boiler and/or circ' pump.