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HVAC
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c. NOISE WHILE OPERATING A/C SYSTEM
TROUBLESHOOTING HINTS
Magnetic clutch operation noise-Step 4
A/C compressor vane noise -Step 5-13
A/C compressor slippage noise -Step 14-17
Hose or refrigerant line interference noise -Step 18
1
Inspect A/C compressor vane noise
Is there a jingling, popping, beeping, or buzzing
sound
(A/C compressor vane noise)?
Yes Go to Step 5.
No Go to next step.
2
Inspect A/C compressor slippage noise
Is there a squeaking or whirling sound
(A/C com-
pressor slippage noise
)?
Yes Go to Step 14.
No Go to next step.
3
Inspect A/C compressor interference noise
Is there a rattling or vibrating sound
(Interference
noise)?
Yes Go to Step 18.
No Go to next step.
4
Inspect magnetic clutch operation noise
Is there clicking sound
(Magnetic clutch operation
noise)?
Yes
Adjust clearance between pressure
plate of magnetic clutch and A/C
compressor pulley, then go to Step
19.
No
Condition is normal. (
Recheck mal-
function symptoms.)
5
Inspect A/C compressor noise time
Is noise heard continuously for more than 3 seconds
after A/C compressor comes on?
Yes Go to next step,
No
Condition is normal.
(Noise occurs for
2-3 seconds immediately after A/C
compressor turns on.)
6 Inspect idle speed Is it okay?
Yes Go to next step.
No Adjust idle speed, then go to Step 19.
7
Inspect refrigerant amount. See refrigerant system
service procedures, refrigerant charge check
Is it okay?
Yes Go to Step 10.
No Go to next step.
8
Inspect refrigerant line
Is piping free of damage and cracks?
Are piping connections free of oil grime?
(Visual Inspection)
Are piping connections free of gas leakage?
Are piping installation points on condense free of
gas leakage?
Are piping installation points on receiver/drier free
of gas leakage?
Are piping installation pints on A/C Compressor
free of gas leakage?
Are piping installation points on cooling unit free of
gas leakage.
Perform gas leak inspection using gas leak tester.
Are above items okay?
Yes Go to next step.
No
If piping or A/C component
(s)
is
damaged or cracked, replace then go
to Step
19.Ifthere is gas leakage,
repair or replace connection and re-
place condenser, then go Step 19.
9
Inspect evaporator piping connections in cooling unit
for gas leakage
Are piping connections for evaporator in cooling unit
free of gas leakage?
Yes
Adjust refrigerant amount to specified
level, then go to Step 19.
No
If piping damaged or cracked, replace
then go to Step 19.
If there is gas leakage, repair or re-
place connection and replace
condenser then go to Step 19.