Performing preventive maintenance on any refrigeration system is necessary to keep the system operating at peak efficiency. Owners of large refrigeration systems understand this and usually perform routine maintenance on their systems.

But many times smaller fractional horsepower, air-cooled systems are left running without any regularly performed maintenance — until there is a problem. Smaller problems left unresolved could result in a major failure.

Maintenance inspections on fractional horsepower systems do not need to be very complex, but they should be detailed enough to ensure the system is operating properly. Below is a list of services that should be performed:

  • Record the make, model, and serial numbers. Having this information recorded for each piece of equipment will allow the service technician to keep track of any suggested repairs.

  • Check the condition of the condenser and evaporator coils and clean if necessary. It is very important to check the condition of the condenser coil. If the unit is installed in a greasy environment, the condenser coil can easily become matted with grease and cause problems for the system. The evaporator coil should also be checked for dirt and for abnormal amounts of frosting.

  • Check and record the suction and discharge pressures. This may not always be practical, since many times these systems will not have any service valves installed. Such valves can be added; but if the system seems to be operating normally, this is not necessary and may even cause a problem.

  • Check the condition of any electrical connections and cords. Any electrical connections, wiring, or cords that look discolored or frayed should be replaced.

  • Check door hinge screws for tightness. Loose screws will cause damage to the hinge as well as to the threads of the screw and its insert.

  • Check the condition of the door gaskets. Any gasket that is worn should be replaced. Also check that the door is closing properly and adjust if needed.

  • Check the amperage draw of the compressor and compare to the manufacturer’s specifications. If the amperage draw of the compressor is outside of its rated conditions, determine the cause, and notify the customer.

  • Check the drain line for clogs or obstructions. Also check the drain pan, and verify that it is aligned with the drain tube. If the unit uses a heated drain pan, make sure it is heating properly.

  • Check the evaporator’s airflow pattern for any obstructions or blockages. Make sure the product is not stacked in a manner that will cause a problem with airflow patterns within the case.

  • Check and record the case temperature. This final check will verify that the system is functioning within its design parameters.

    Marchese is owner of Coldtronics of Pittsburgh, PA. He can be reached at 412-734-4433; (e-mail); (website).

    Publication date: 03/04/2002