AboutHoward Livingston Expertise Can answer questions on electrical control circuits, power supply,airflow & distribution, electrical components,refrigerant problems,gas, electric & propane furnaces.No boiler or refrigerator or oil fired furnaces experience.Just HVAC questions please.
Experience 35 years experience in residential & light commercial repair & installation.
Question I have an American Standard Freedom 90 furnace with a brand new (yesterday) American Standard Allegiance 15 outdoor condenser. Just changed the condenser and evap. core because it had failed. I just found out why...the blower fan on the furnace is stopping and starting causing the evap core to freeze up. I shut off the power to the furnace and took the covers off. When I turn the power back on and close the safety switch the IFC clicks and the light starts blinking. On the third blink the blower fan tries to start and then drops out. After trying it a few times it does start and then will start every time. The blinking lights are supposed to help me troubleshoot but they seem to reset every time the blower tries to start. I would call my tech but I am worried that he is just going to say that the board is bad. I don't know how much an IFC board costs but I don't want to buy it unless it is really the problem.
Answer When in cool mode the thermostat activates the inside fan when cooling is activated. If you have a digital thermostat it needs testing. If it is OK, the circuit board has the fan relay on it that may be the problem. If so, the whole board has to be changed. Costs vary like crazy for rhw different brands.
