Opinion on Taco Zone Control

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Jcc583

New Member
Nov 30, 2018
60
New York
When I purchased my home it came with a 150,000 BTU propane furnace with baseboard heat and an indirect water heater. The home has three zones One being DHW. The system is a supply and return and the zone valves are Honeywell. The series of operation is simply the zones are wired in parallel with the end switches going to T and TV. My question is I purchased a taco ZVC 404 to use with the addition of my wood boiler and thermal storage but am trying to find the benefits in changing its simplicity of parallel wiring to separating into individual zone controls any feedback is appreciated!
 
How big is the home, heat load, family & indirect water heater?

With parallel wiring, all 3 zones could call for heat at the same time. The propane boiler might be able to keep up with that but your wood boiler & storage may not.

Swapping to the ZVC 404 will allow you to run the indirect as priority as it will delay space heating until DHW is satisfied. The ZVC 404 also has some extra relay connections & NO / NC end switches that would allow for some flexibility with integrating the wood boiler & storage.

I have a 121 K oil boiler with tankless coil and 2 zones. I want to add zone 3 (mud room) zone 4 (garage) and zone 5 (indirect DHW) when I get the wood & storage hooked up. It's a little complicated to explain but I think I came up with a relatively easy control scheme to make the existing oil boiler aquastat play well with the ZVC 406 that I picked up.
 
How big is the home, heat load, family & indirect water heater?

With parallel wiring, all 3 zones could call for heat at the same time. The propane boiler might be able to keep up with that but your wood boiler & storage may not.

Swapping to the ZVC 404 will allow you to run the indirect as priority as it will delay space heating until DHW is satisfied. The ZVC 404 also has some extra relay connections & NO / NC end switches that would allow for some flexibility with integrating the wood boiler & storage.

I have a 121 K oil boiler with tankless coil and 2 zones. I want to add zone 3 (mud room) zone 4 (garage) and zone 5 (indirect DHW) when I get the wood & storage hooked up. It's a little complicated to explain but I think I came up with a relatively easy control scheme to make the existing oil boiler aquastat play well with the ZVC 406 that I picked up.
I ran my endswitches through two relays one that signals load pump and one that runs through storage aquastat to decide to fire boiler or pull from storage. I know how complicated it can be! Could you explain your plan? I struggled putting my storage temp as the desicion maker in the taco control. I’m thinking because my thermal tank aquastat is only a spst “2 post”. I appreciate the insight!