초록 ▼

The present invention involves a two stage furnace and a method of warming its heat exchanger. The furnace includes a gas valve with low and high combustion settings, and inducer and circulator fans with low and high speed settings. When a call for heat is present, the inducer fan and gas valve oper

The present invention involves a two stage furnace and a method of warming its heat exchanger. The furnace includes a gas valve with low and high combustion settings, and inducer and circulator fans with low and high speed settings. When a call for heat is present, the inducer fan and gas valve operate at high. After a heat on delay period, the circulator fan operates at low speed to provide an initial warm stream of air from the furnace.

대표청구항 ▼

In a two stage furnace having a gas burner and at least one heat exchanger, a method of initially warming the heat exchanger comprising the steps of: providing a gas valve having a low and high combustion operating setting, an inducer fan having a low and high speed operating setting, and a circulat

In a two stage furnace having a gas burner and at least one heat exchanger, a method of initially warming the heat exchanger comprising the steps of: providing a gas valve having a low and high combustion operating setting, an inducer fan having a low and high speed operating setting, and a circulator fan having a low and high speed operating setting; determining that the furnace has been enabled; operating said gas valve on said high combustion setting and said inducer fan or said high speed setting; delaying said circulator fan by a predetermined heat on delay and then operating said circulator fan at said low speed setting; determining when a predetermined warmup time has expired, and after expiration operating said gas valve, said inducer fan, and said circulator fan at one of the combustion settings.