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thermostat controls help
- Thread starter buffer72
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It depends on what you are talking about. I assume you are talking about package units. If so then generally there is a transformer built into the unit that goes to a terminal strip. The standard designations on the terminal strip are as follow:
R - 24 V
C - Common leg of 24 V
G - Fan
Y - Cooling
W - Heating
O - Reversing valve if it's a heat pump.
If it's not a package unit, then generally the controls contractor will provide whatever transformer(s) may be required. Depending on the situation (complex) a 120V circuit may need to be provided if it's a more complex control situation. If not then many times, the contractor will step down power from the main incoming power to the unit.
R - 24 V
C - Common leg of 24 V
G - Fan
Y - Cooling
W - Heating
O - Reversing valve if it's a heat pump.
If it's not a package unit, then generally the controls contractor will provide whatever transformer(s) may be required. Depending on the situation (complex) a 120V circuit may need to be provided if it's a more complex control situation. If not then many times, the contractor will step down power from the main incoming power to the unit.
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