I have a Weil McLein 230 boiler. It has one input for thermostat and one
output for circulator.
It's going into an existing structure with two zones, two pumps, two
thermostats. No zone valves, pumps are on boiler input, so one running
doesn't cause other zone to circulate.
My question is, how do I wire both thermostats into the boiler, without
feedback triggering the second pump? Both pumps run via relay.
I've tried diodes, but can't seem to get anything to work right. Was
wondering if someone could point me to a wiring diagram of the electrical
layout in the above application.