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Customer Service

Warranty Information

HVAC Service Documents

Recommended Charging Procedure
Charge Determination
Basic Troubleshooting
R134a and PAG Oil Handling
Compressor Oil Handling
Compressor Troubleshooting
Blower Motor
Glossary of Common HVAC components

Gauge Diagnostics

Using Gauges for Troubleshooting
Air in cooling system (insufficient suction)
Defective expansion valve
Excessive refrigerant
Insufficient compressor operation
Insufficient refrigerant
Moisture Intrusion
Refrigerant does not circulate

Summary Table of Gauge Diagnostics



Basic Troubleshooting Guide

Noise from a loose drive belt, especially noticeable when compressor first starts?
Noise from the compressor area?
Noise from the compressor housing?
Mud or Dirt adhered to the condenser?
Condenser / Radiator fans operating properly?
Any oil contamination in pipe unions or on the compressor?
Noise from the blower motor?


Noise from a loose drive belt, especially noticeable when compressor first starts?

A lose or worn drive belt makes a slapping noise and a high pitch squealing noise when in operation and during start-up. Check and adjust drive belt tension, replace if necessary.  A worn drive belt will show excessive cracking, and fraying along the edges of the belt.

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Noise from the compressor area?

Check the compressor bolts for any loose bolts. Tighten if necessary.

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Noise from the compressor housing?

Suction/discharge valve damage and internal wear are possible sources of noise from within the compressor.

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Mud or Dirt adhered to the condenser?

Remove any mud and debris from the condenser face.  The material will create excessive condenser pressures and lower BTU efficiency of the system. During the cleaning process make sure no fins are folded over.  A fin comb can be used to straighten any fins that have been bent over.

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Condenser / Radiator fans operating properly?

Check drive belts, viscous drives and fan motors. Replace if necessary.

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Any oil contamination in pipe unions or on the compressor?

Option 1: This suggests a refrigeration leak at the point where AC oil collects.  Use a leak detector on the site where the oil has collected and around the area.  The detector will give an audible indication of a leak.

Option 2: Carefully check that all fittings and gaskets are sealed. Torque values can be found on recommended torque page.

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Noise from the blower motor?

Option 1: If the fan motor is noisy this indicates improper operation.  Disassemble fan and repair.

Option 2: The fan will also make noise if there is foreign matter collected on the fan surface.  This would create an out of balance issue. Cleaning the blades of the fan and replacement would repair this issue.

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Information obtained in ZEXEL Service Manual
Basic service procedures for R134a Air Conditioning Systems.
Copyright 1992
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Perrin Manufacturing is committed to providing you with superior products and services; we renew this pledge through continual improvement of our products and motivation of our staff.

We faithfully comply with all of the requirements of our ISO 9001:2008 Quality Management System, the most current edition of the standard. Beyond that, our highly trained quality staff persistently search for new ways to improve the effectiveness of our system.
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