This morning I woke up to a cold bedroom. When I went over to the thermostat the screen was completely blank. This system is a Carrier heat pump system that supplies the top floor of our home. I checked all the CB's on the panel. The indoor unit is in the attic so I went up there to start troubleshooting. I confirmed voltage on the back sides of the four fuses where power enters the unit. and eventually made my way up to the circuit board where I discovered a blown 5 amp fuse. I drove to the auto parts store and bought a pack of 5 fuses. I replaced the fuse, powered up the system and everything seemed fine for about two minutes, then the new fuse blew. I tested the voltage from the transformer and although it was a little high (28 volts) it was steady as a rock. I check all the the connections and looked for anything that may be shorted but everything looks fine. I replaced the fuse again, powered up the system and went down to the thermostat. I set the fan to ON and it came on. Great. I put it back to AUTO and switched the mode from AUTO to HEAT and set the temp for 76. The system said "Wait" for a few minutes and then the screen went blank again. Another blown fuse.
Do you think there is a problem with the compressor and it's overloading the circuit? One of our outdoor units had been making a bit of a "whining" sound when the compressor would activate this summer but I hadn't had time to figure out which one it was and determine if it was a problem.
If it's serious I don't mind calling in the pro's. I just want to make sure I've covered all the simple stuff so I don't pay $150 to tighten a screw or replace a fuse...again.