CONTENTS
SOUNDS
UNDERHOOD
CONTINUOUS

NOISY AIR CONDITIONING SYSTEM

CONDITION(S)

• NOISE IN AIR CONDITIONING SYSTEM WHILE ON

POTENTIAL CAUSE(S)

CHECK THESE FIRST:

1. LOOSE OR WORN COMPRESSOR DRIVE BELT
Tighten or replace compressor drive belt.

2. LOOSE OR WORN COMPRESSOR
Have compressor professionally serviced.

3. LOW COMPRESSOR OIL LEVEL
Have compressor oil level professionally adjusted.

CHECK THESE NEXT:

4. MAGNETIC CLUTCH SLIPS OR MAKES NOISE
Have magnetic clutch professionally repaired.

5. LOOSE OR WORN BLOWER MOTOR
Have blower motor professionally serviced.

6. EXCESSIVE REFRIGERANT CHARGE IN SYSTEM; CONFIRMED BY RUMBLING OR THUMPING NOISE AND BUBBLES IN SIGHT GLASS
Have refrigerant level professionally reduced.

CHECK THESE LAST:

7. INADEQUATE REFRIGERANT CHARGE IN SYSTEM; CONFIRMED BY HISSING SOUND AT EXPANSION VALVE ACCOMPANIED BY BUBBLES AND CLOUDINESS IN SIGHT GLASS
Have refrigerant level professionally increased.

8. MOISTURE IN SYSTEM; CONFIRMED BY NOISE AT EXPANSION VALVE
Have refrigerant professionally replaced and any leaks repaired.

9. HIGH PRESSURE SERVICE VALVE CLOSED; CONFIRMED BY COMPRESSOR KNOCK
Have high pressure service valve professionally set.

CONTENTS
LIGHT MOAN
HISSING SOUND