What is the proper high limit fan setting for a 1994 York Stellar gas furnace? It is currently set to 150 and that allows it to run on a 10 mins on/4 mins off cycle. Is that about right?
The High temperature limit controls how much heat your furnace will deliver. The higher the temperature the hotter the air it delivers. At the same time, the higher the temperature, the hotter the exhaust that is wasted energy. The amount of heat you need relates to outside temperature. Some more sophisticated controls would adjust the high limit to change with outside temperature However, with a fixed limit, the lower the limit the more efficient your operation. If you are looking for maximum efficiency, then you should lower the limit to the point where the fan runs continuously on a cold day. If the fan shuts down, it means that you are making more heat in the furnace than you need. You might want to change the high limit
to be higher in the colder part of the winter when you need maximum heat, and then lower it when the outside temperature worms up.
If you are getting adequate heat at 150 Deg. you should not go higher, because the higher the limit, the lower the efficiency and the greater the stress on the furnace.
on Mar 02, 2019