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ZVC the way it ought to be

archibald tuttle
archibald tuttle Member Posts: 1,085
edited February 26 in Radiant Heating
my second 570 job this week. and there was already a ZVC 504. so i didn't have to hack up the 570s, as much fun as that is. but i was disappointed that access to the common terminal was not convenient or well marked and the wiring didn't explain which of the 24V terminals was actually the common. ironically the red wire from the transformer was common, meaning it pairs with the red thermostat wire. i think this is an older version. maybe this has been improved.

i was replacing a thermostat with a 3 wire stat. and in the "While you're there" mode, upgraded the control with my override switching on-off-thermstat for each zone. if a fourth zone is ever used, there is one more knockout for that switch.

7/16 stainless washers work perfectly as switch bushings for those knockouts although I was dave sweet would have just included switches on the board somewhere.