Common HVAC problems

The most common HVAC problems by a true hvac service technician:

  1. Bad compacitor
  2. Low refrigerant
  3. Clogged condensation drain line
  4. Bad control board
  5. Bad condenser fan motor
  6. Blower motor or compressor shorted to ground (breaker keeps tripping)
  7. Very dirty furnace filter (medium grade filter)
  8. Tripped AC breaker (could be shorted circuit, or bad compressor)
  9. There are six way tie at #9:
    • Empty refrigerant (very big leak)
    • Very dirty condenser coil (clean the condenser coil using water hose)
    • Bad contactor
    • Evaporator drain pan leaks
    • Mouse damage
    • Broken wires
  10. There are two way tie at 10th place:
    • Locked up compressor
    • Insufficient compressor
Other issues:
Furnace switch was turned off
Disconnect fuses blown
Evaporator clogged (no filter or very low grade filter or filter is not changed for long time or filter is not covering the entire duct)
Restricted metering device (TXV or piston, TXV more common)
Bad thermostat
Furnace door switch is not working right.

95% of issues related to electrical components


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