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ZVC403 doesn't work as designed for me
I'm redoing my boiler, and am re-using a set of three Taco ZV403-4 controllers, and some Honeywell V8043E1012 zone valves.
When I use the zone control lines from the Taco (as the installation instructions suggest), they don't open the valve in some cases. Sometimes they work. Sometimes they take a long time to open. Sometimes they just sit in place. My Erie pop top hums and never moves. I think the Taco zone valve lines must be a bit under powered.
I notices the person who originally used the valves with these controllers wired the valve motors to the thermostat lines. That would work, though it would be a bit of a pain at this point. I thought it was bizarre when I pulled them out, but maybe it's the right way to use them.
Is there some way to get it work as the wiring diagram in the ZV403 would suggest, or should I give up an run the motors off the thermostats?