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Taco ZVC404 to Tekmar 508's

With the 500 series stats, you need to pull dedicated 24V power to C & R and then the Heat Terminals (5&6) go to the TT on the ZVC Control. (The ZVC control should have separate 24V power available to accomplish this).

If you are using a taco EBV, you would jumper terminals 3&4 on your zone valve terminals on the ZVC. It also may vary depending on where you choose to pull 24V from.



  • fatty_2
    fatty_2 Member Posts: 54

    So I'm trying out some tekmar products - and I initially just wired up some temporary power to the taco zone valve control, hooked up one zone valve and one thermostat (of several) to see the display on the stat: nothing happened. I cant get even a blip of life out of these thermostats. The ZVC LED indicates the circuit is complete, light stays on... still nothing out of the stat. I wired the zone valve just to see (Taco EBV) and it was powered and fine. I tried all of the stats (new out of box) and rewired it twice. I just don't get it!

    120V --14ga--> 24V transformer (ZVC404) ----> Zone 1 TT terminal(ZVC404) --18ga--> C & R terminals (Tek508)

  • fatty_2
    fatty_2 Member Posts: 54

    paul thanks, that was extremely helpful
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