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Preventative Maintenance for Heating, Cooling and Refrigeration Systems(over)


Preventative maintenance is a planned activity to clean, inspect, and test heating, cooling, and refrigeration equipment to ensure they run efficiently, reliably, and have a long service life. Most businesses practice reactive maintenance or “run it till it breaks” which has low upfront costs but will ultimately degrade equipment performance and reliability. Over 50% of business owners still operate with a philosophy of reactive maintenance.

The Basics:

  • Replace all filters quarterly
  • Inspect and clean evaporator and condenser coils quarterly
  • Inspect and lubricate fan motors quarterly
  • Replace all belts annually
  • 30 Point Maintenance Check (see below list)


Special Issues: 

Thermostat Settings :- Programmable thermostats can be confusing so if there are any questions these should be checked out. A lot of energy is wasted by not having the units “set back” when the building is unoccupied. Settings should be checked and adjusted to prevent excessive run time, maintain comfortable conditions during occupied hours, and achieve the maximum practical setback/setup during unoccupied hours. 
Economizer Damper Controls :-  These controls provide excellent energy savings. If operating properly they can save at least 10% of operating costs of the unit. However, if they are not inspected and tested at least twice a year there is a chance they might not be working properly. About half of all newly installed economizers don’t work properly. If they are not working properly they can waste more energy than they save.

30 Point Check List :-
  • Check system for proper refrigerant charge 
  • Check compressor amps 
  • Check condenser fan amps 
  • Check condenser coil 
  • Check contactor points 
  • Check capacitor
  • Check thermostat (level)
  • Check thermostat calibration 
  • Check temperature split at evaporator coil 
  • Check blower amps 
  • Check heat strip amps 
  • Check safety controls 
  • Check all electrical connections 
  • Check air circulation
  • Check for air leaks at plenum 
  • Check all visual leaks
  • Change filter if available 
  • Lubricate all moving parts where necessary 
  • Check and clean evaporator coil 
  • Flush or blowout condensate line 
  • Check for excessive vibration 
  • Level a/c condenser 
  • Check defrost control 
  • Clean, check & adjust condenser fan 
  • Check condensing temperature split at condensing coil 
  • Clean indoor blower 
  • Check the crankcase heater 
  • Check final performance




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