Many new, high efficiency furnaces have the option of two or more stages of heat output (correlating to gas valve position) and have variable speed furnace blower motors. These new furnaces should be accompanied by a matching thermostat in order to take advantage of these variable heating and distribution outputs. A matching programmable thermostat may reduce energy use and produce more precise comfort levels by maintaining more consistent low-fire operation when heating demands are lower, limiting intermittent high-fire operation (short cycling) of the furnace. Low voltage thermostat (LVT) wiring should be utilized that matches the new thermostat having an appropriate number of wires.