Hello all. I just installed a new Honeywell RTH9580 to replace my old TH4110D1007. I have a Sentry S-120 EDP gas fired boiler for heat with Honeywell V8043E1012 zone valves. Then I have a central air conditioner with a York MC48C3XC1A evaporator coil.
On my old Honeywell TH4110D1007 thermostat, I had R and W going to my heat and Rc, Y and G going to my AC. No common wire. The thermostat was powered by two AA batteries.
I had 18/3 wire going to my heat with the spare wire being unused since this house was built in 1980. So I put the spare wire to use as a new common wire for this new Honeywell RTH9580 thermostat.
Here is how I wired the new thermostat:
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Their instructions say to remove the jumper loop if you have both R and Rc wires which I do. However, the thermostat will not power on unless I add that jumper loop to that current wiring setup.
I have the heat successfully working with that setup but I have not tried to turn on the AC just yet. I am afraid to fire up the AC because of that jumper loop. I contacted Honeywell and they are asking me to swap my R and Rc wires and remove the jumper loop to see what happens. They position that as a "we'd like to try something". I understand what they're trying to do, but I don't like their trial and error attitude. I also believe if the R and Rc wires are swapped, then my heat and AC calls would be backwards.
So before I humor Honeywell, put your electrical engineering hats on and send me your thoughts and comments about my situation please.
I could always leave my wiring setup and just try to fire up the AC regardless. But I'm just worried with that jumper loop.
Thanks in advance people!
Their instructions say to remove the jumper loop if you have both R and Rc wires which I do. However, the thermostat will not power on unless I add that jumper loop to that current wiring setup.
I have the heat successfully working with that setup but I have not tried to turn on the AC just yet. I am afraid to fire up the AC because of that jumper loop. I contacted Honeywell and they are asking me to swap my R and Rc wires and remove the jumper loop to see what happens. They position that as a "we'd like to try something". I understand what they're trying to do, but I don't like their trial and error attitude. I also believe if the R and Rc wires are swapped, then my heat and AC calls would be backwards.
So before I humor Honeywell, put your electrical engineering hats on and send me your thoughts and comments about my situation please.
I could always leave my wiring setup and just try to fire up the AC regardless. But I'm just worried with that jumper loop.
Thanks in advance people!