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Cab Air Conditioning Standards for Diagnosis and Repair
High A/C Costs
It is important to establish standards for Cab A/C maintenance because Cab A/C is one of the highest cost accessories on vehicles today. A study was conducted to identify high cost components and establish standards for Cab A/C diagnostic and repair procedure.
The results indicated that following these guidelines have:
lowered overall Cab A/C cost,
reduced Cab A/C breakdowns,
increased driver satisfaction,
reduced labor hours spent on non-scheduled Cab A/C repairs, and
created a pro-active approach to Cab A/C Preventive Maintenance.
Air Conditioning Technicians must successfully complete Cab Air Diagnostics training, follow trained procedures, and strictly adhere to standards when performing inspections, diagnostics, repairs and/or making adjustments.
Driver Benefits
Providing excellent Cab A/C maintenance and repairs increases vehicle utilization and driver confidence level. It also provides drivers the comfort they need on the highway and during rest periods.
If system failure was the result of a mechanical failure or if any sign of system contamination is apparent, the system must be properly flushed and properly purged.
Contaminated refrigerants must never be reused in a A/C system.
When the refrigerant system has to be opened to ambient conditions, the drier/accumulator must be replaced.
Evacuate system and perform a vacuum test with a quality micron gauge.
Refrigerant systems should never be topped off to get the vehicle back on the road.
Each Technician working on Cab A/C systems must be Section 609 certified.
A/C systems generally should not be converted to another refrigerant.
The Dayco Krikit gauge I P/N U29 93865 (for V Belts), and Krikit II P/N U29 93866 (for multi-rib belts) are required tools used for checking and adjusting belt tension.
If a belt is found to be 20 lbs. or more under the recommended tension, replace the belt. Adjust new belts using Krikit gauges listed above.
Keep records of employees' Qualification/Certification to perform work on Cab A/C.
Service port caps must be reinstalled after A/C service is completed.
Refrigerant oil should be purchased in small containers.
Pressure washers should not be used to clean condenser fins.
