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Need help with boiler and Taco ZVC403-4 (I added second zone to system)
I have an older home with boiler and cast iron radiators and cast iron baseboards. I added a second zone of copper finned baseboard to the upstairs- as there was no heating on the second floor. I have added a second pump and zone valves to the old and new zones. I have a Taco ZVC403-4 controller that I was told should be all that I need (and I believe that may be incorrect). Can I control and drive the 2 zone valves and 2 motors independently as heat is requested from one or both of the zones? Looking at the wiring diagram for the circulator pumps, there is one connection for a system pump (which runs whenever ANY zone valve opens.) And connections for a secondary pump to either a NO or NC terminal. What I need is for either zone pump to be able to run as heat is needed independently. Any help would be greatly appreciated. I think I may need additional or different equipment.
As a final ditch effort I called Taco support and they say I need to add a SR501 or SR502 depending on who I talked to there....... ? I’m totally confused now. And if so how do I wire them together?