What temperature setting on the furnace

JAMJTX

I am just now starting to learn about my old furnace.  My neighbor told me that her husband installed it for the family that owned this house in 1960.  It is an OLD gas furnace, 3 years older than I am.  It actually seems to be working rather well, although it should probably be replaced.  I did replace the 1960 thermostat.



I noticed that there are 3 temperature settings on the furnace.  I assume this refers to the temperature of the hot air.  They are 150, 200 and 250.  My house is only about 700 square feet.  What should I set this at?

Tim McElwain

What are the numbers

on the temperature control you are looking at? It is probably a Fan/Limit control. If so it should be set for limit at 200 and fan on 140 to 150, fan off 110.



It is a good idea to have a professional HVAC company look at the furnace and have a test done on the heat exchanger to insure it is not cracked. Have them also do a combustion test and tune up. This should be done on an annual basis.



What was the make of thermostat and numbers you took out? What did you replace it with? You want to be careful with replacing thermostats on older systems as some of them are Powerpile self generating systems and thermostat match up is important.