Tagged Questions
0
votes
1answer
42 views
Why isn't my thermostat working?
I have an old Lennox (gas heat only) thermostat. There are 3 wires coming from the wall. Black, yellow and a light blue color (could be a faded green or an old dirty white).
The thermostat wouldn't ...
3
votes
3answers
12k views
Why is my furnace blowing cold air?
My HEIL 7000 natural gas furnace has stopped working what are the most likely causes, and how to verify faulty parts?
Normal operation routine
Thermostat sends "need heat" signal.
Exhaust blower ...
