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Can you provide me with the wiring instructions, I want to replace the old analog thermostat. I have a roof mounted not ducted Advent A/C and a furnace unit.

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The terminal board on the rtu should match fairly closely with the letter designations on the thermostat. R, W ,(possibly W2) G, Y, (possibly Y2) and C. W2 and Y2 are most likely NOT used on a small capacity rtu (roof top unit) as those terminals are for a second stage of heating and a second stage of cooling.

The thermostat terminals should be Rc, Rh, W, G, Y and C (common). IF the replacement thermostat is programmable the common terminal should be used because that allows the thermostat to run on 24vac and not just battery power.

There should be a factory jumper installed across Rc and Rh and that should stay in place as the two terminals are for systems that have TWO different control transformers. Small capacity rtu's will have only ONE transformer.

Some rtu's have a W2 terminal as well as a Y2 terminal even though they do not have the second stages of heat. You have to determine exactly what your system is prior to changing the thermostat.

Posted on Apr 14, 2015


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