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Taco sr503 relay question
I'm only using zone 1 and 2 and the tt contact goes to the first tt input on the boiler.
I want to move the 2nd zone to the priority zone 3 and use the priority tt to the second tt input on the boiler to run a separate odr/temp curve. But I want the priority function inactive
I read the directions a few times and am a little confused. Do both end switch close when the priority zone calls for heat? If so it is going to kill my plan
Thanks
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Comments
The -EXP controllers have two separate end switches (XX). The "Main End Switch" only closes upon a heat call from any heating zone, in your case Zone 1 and Zone 2.
The "Priority End Switch" only closes when Zone 3, the priority zone, is calling for heat as long as the priority switch is on.
Dave H.
Thanks
I'm getting 7 volts across rw on a the zones NOT calling for heat. Is this normal?
It is a battery thermostat with only 2 wires
When the thermostat is closed, it should read 0v across TT