Preventive Maintenance

You wouldn’t drive your car 100,000 miles without changing your oil, would you?  The same logic holds true for your home comfort system.  Regular preventative maintenance is the best way to ensure trouble-free operation and peak performance.  Pre-season is also important, it can help avoid a system failure in severe hot or cold weather when you need it the most.  Plus the added bonus of saving on your energy bill preventive maintenance

When Should I do Maintenance?

For a system that heats and cools: Perform maintenance in the Spring and Fall

  • Cooling only: Once a year-end of Spring
  • Heating only: Once a year-end of Fall

All Star provides priority services for their customers who have an annual maintenance or service agreement. Bi-annual preventative maintenance will ensure that your system runs as efficiently as possible. All Star technicians will perform the following tasks, depending on the unit. Snohomish Snoqualmie Seattle heating and cooling hvac

Outdoor Units

Outdoor Units

Outdoor Units


  • Inspect unit for proper refrigerant levels and adjust if necessary
  • Clean dirt, leaves, and debris from inside cabinet
  • Inspect base pan for restricted drain openings—remove obstructions as necessary
  • Inspect coil and cabinet—clean as needed
  • Inspect fan motor and fan blades for wear and damage— on older models lubricate as needed
  • Inspect control box, associated controls/accessories, wiring and connections.  Controls may include, relays, circuit boards, capacitors, sump heat, and other accessories.  All control box and electrical parts will be checked for wear and damage
  • Inspect compressor and associated tubing for damage heating and cooling

Indoor Units

Outdoor Units

Outdoor Units


  • Inspect and clean blower assembly (includes blower housing, blower wheel, and motor)
  • On older models, lubricate motor and inspect and replace fan belt if needed
  • Check combustion blower housing for lint and debris, clean if necessary
  • Inspect evaporator coil, drain pan, and condensate drain lines.  Clean as needed
  • Inspect for gas leaks, in gas furnaces
  • Inspect burner assembly—clean and adjust as needed
  • Inspect ignition system and safety controls—clean and adjust as needed
  • Inspect heat exchanger or heating elements
  • Inspect flue system—check for proper attachment to the furnace, any dislocated sections, and signs of corrosion.  Replace if necessary
  • Inspect control box, associated controls, and wiring connections
  • Clean and replace air filters
  • Inspect the conditioned airflow system (ductwork) check for leaks. Snohomish preventive maintenance heating and cooling

While your system is operating...


  • Monitor system starting characteristics and capabilities
  • Listen for abnormal noises
  • Search for sources of unusual odors
  • Monitor air conditioning and heat pump systems for correct refrigerant charge
  • Measure outdoor dry bulb temperature
  • Measure indoor and outdoor wet bulb temperature
  • Measure high and low side system pressure
  • Monitor gas furnace for correct line and manifold gas pressure—make adjustment as needed
  • Measure temperature rise and adjust airflow as needed
  • Check vent system for proper operation
  • Monitor system for correct line and load volts/amps
  • Monitor system operation per manufacturer's specifications
  • Provide system operation report and recommend repairs or replacements as needed preventive maintenance


NOTE:  Trane recommends all maintenance and service work be performed by a professional HVAC technician that holds the appropriate credentials to install and service heating and air conditioning equipment.  

All Star is a Trane Comfort Specialist and NATE certified.