BASIC AC & REFRIGERATION SYSTEM SERVICE

     Rooftop units should have a minimum of four preventative maintenance checks each year, including one cooling startup and one heating startup. The checks would include one belt replacement, if applicable, and four filter changes.

     If the air conditioning unit and duct system will allow higher efficiency pleated filters, consider putting them in. Usually you can use a two-inch pleated filter in roof top units under 30 tons. The pleated filter will give additional rigidity that will protect the filter if it gets wet.

     Once a year, have coils, the condenser and evaporator cleaned with a low-cost hand sprayer. First "brush clean" the coil if necessary. Then, using a low suds detergent at the proper dilution strength, clean both coils and rinse. The evaporator tends to be "self rinsing" in the cooling mode . Cleaning the coils with a hand sprayer should be sufficient if other preventative maintenance has been performed at recommended intervals.

Preventative Maintenance Checklists

     The following preventive maintenance checklists is consistent with major manufactures.  We recommend a minimum of two inspections, performed at the start of each "season" (cooling or heating).  

     We also recommend that the checklists be followed for a midseason checkup of your system.

HVAC SYSTEM PREVENTIVE MAINTENANCE CHECKS
	COOLING SYSTEM
	Replace all air filters. (Preferably Pleated)
	Replace blower belt(s).
	Inspect and lubricate blower bearings
	Clean heating, evaporator and condenser coils.
	Verify heating/cooling systems are operable.
	Check refrigerant and compressor oil levels on compressors with sight glass.
	Check head and suction pressure
	Check and adjust all operating and safety controls.
	Check compressor(s) and motor(s) using a Megometer
	Clean condensate drain, trap, and pan.
	Verify economizer dampers are set and operable.
	COOLING SYSTEM MID-SEASON CHECKS
	Replace all air filters. (Preferably Pleated)
	Inspect and adjust belts and blower.
	Inspect and lubricate blower bearings.
	Clean heating, evaporator and condenser coils.
	Verify heating/cooling systems are operable.
	Clean condensate drain, trap, and pan.
	Check thermostat calibration.
	Verify economizer dampers are set and operable.
	HEATING SYSTEM
	Replace all air filters. (Preferably Pleated)
	Inspect blower and belts.
	Inspect and lubricate blower bearings and motor.
	Clean heating, evaporator and condenser coils.
	Test operation of heating systems. Test Emergency heat if your system is a heat pump.
	Verify heating/cooling systems are operable.
	Check and adjust all operating and safety controls.
	Clean condensate drain, trap, and pan.
	Verify economizer dampers are set and operational
	HEATING SYSTEM MID-SEASON CHECKS
	Replace all air filters. (Preferably Pleated)
	Inspect and adjust belts and blower.
	Inspect and lubricate blower bearings.
	Clean heating, evaporator and condenser coils.
	Verify heating/cooling systems are operable.
	Clean condensate drain, trap, and pan.
	Check thermostat calibration.
	Verify economizer dampers are set and operable.
REFRIGERATION SYSTEM PREVENTIVE MAINTENANCE CHECKS
	Evaporator Components
	Check for proper defrosts and cleanliness
	Tighten all electrical connections
	Check motors and fans
	Clean and check that motors rotate freely
	Lubricate motors if applicable. Most motors are permanently lubricated
	Check defrost heaters
	Clean drain pan and drain
	Clean evaporator coils with a food-grade cleaning foam
	Check and record box temperature
	Compressor Components
	Tighten all electrical connections.
	Check electrical components (contactors, capacitors, etc.)
	Check defrost timer and defrost controls
	Check operation of the safety and operating control system
	Check oil level in compressor, if applicable
	Check condition of refrigerant line insulation
	Check for proper refrigerant level in system
	Check refrigerant sub-cooling, leaving condenser if applicable
	Check refrigerant superheat at the compressor, if applicable
	Check discharge line temperature at the compressor
	Check capillary tubes for vibration wear
	Check and record refrigerant discharge pressure
	Check and record refrigerant suction pressure
	Condenser Components
	Clean condenser coils every six months or sooner depending on local conditions
	Check motors and fans. Clean blades and check to see that the motor rotates freely
	Lubricate motors, if applicable. Most motors are permanently lubricated
	Electrical System
	Check voltage at compressor for voltage balance and voltag e drop
	Check amperage at compressor for balance and over-current
	Check defrost heater amperage in all circuits
ICE MACHINE PREVENTIVE MAINTENANCE CHECKS
	Replace water filters based on local experience and unit recommendations
	Observe an ice harvest for normal operation
	Clean ice production and storage components
REFRIGERATOR PREVENTIVE MAINTENANCE CHECKS
	Clean condensing coil. If located at the bottom of a freestanding unit, condensing coils require more attention because of the dust in vacuuming or sweeping
	Check defrost heater(s)
	Check box temperature

Stedi-Power, Inc
5044 B U Bowman Drive #102
Buford, Georgia 30518
PHONE: (678) 546-6780

Last Updated: 07 Jun 2004
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