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 Hi, we have a Heil DC 90 Ultra High Efficiency with model # beginning with NTGM. We have not used our unit for approx. one month and the last time used was for heat. When attempting to turn on the A/C unit, nothing. Checked the breaker box, was not tripped. Checked the emergency shut-off switch outside, still in the ON position. Attempted to turn up the thermostat to try the heat, nothing. Tried the fan, nothing. Took off the cover of the unit and examined for any obvious problems, could not see anything. The circuit board appears intact. Not sure if this is important, but we did have a problem with the heat a couple of years ago-blowing cold air. We did have a tech come out and I believe a fuse of some sort was replaced inside the unit. After looking inside the unit, I am completely lost as to where a fuse would even be found...if there is any. Do you have any suggestions for us, or do you think it best to call another tech.
Thanks for your help.
Answer Wait to call a tech. This is for free. Look for a 3 amp fuse, automobile type, plugged in to the circuit board. Pull it out & its probably blown. Got a short circuit in the 24 volt control circuit. Thats what needs fixin'.Can be the contactor coil in the outside unit or 10 other places. Got a dog in the back yard ? They like to chew on wires.
