2 heat 1 cool thermostat wiring problem

Old 07-20-14, 07:05 AM
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2 heat 1 cool thermostat wiring problem

Just installed new 1-stage a/c unit to existing (1 yr old) 2-stage furnace. Thermostat wiring guide (Honeywell FocusPro TH622) has diagrams for 2heat 2cool but not for 2heat 1cool except heat pump. This is just a gas furnace. Can existing thermostat be used, and how should everything be wired? Problem is that fan runs on low speed only, no matter how long the unit is on, and the cooling line is icing and can't keep up with even a few degrees of heat.
Old 07-20-14, 08:08 AM
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Configure the stat for 2 heat 2 cool.

Thermostat Y1 must connect to furnace Y2 (the higher stage Y) to run the correct fan speed with single stage cool two stage heat applications.

Post your furnace make and model number.

Is the air filter and evaporator coil clean?

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