HVAC Preventative Maintenance Checklist

Heating Ventilation and Air Conditioning (HVAC) systems are a critically important part of your house. One of your most essential tasks as a homeowner is to keep your HVAC functioning effectively and efficiently. A poorly maintained HVAC system results in higher energy bills. If the system is not running at its peak efficiency, it will take more and more energy to heat or cool your home to the level at which you feel comfortable. Planned maintenance of your HVAC system means lower energy costs because a well-maintained system reduces energy usage. 

All HVAC systems, even the very best ones, will occasionally have problems. Regular maintenance, however, means fewer repair problems because your HVAC technician will spot them ahead of time. It makes much more sense to replace a frame belt or faulty evaporator before they cause severe problems and costly repairs. Regular maintenance gives an HVAC technician an opportunity to spot these potential issues. The very last thing you want is for your HVAC system to break down when you have a big entertainment night, or a family get together. You should be able to rely on your HVAC system to work at peak efficiency when you need it the most. A regular maintenance plan reduces the chances of a catastrophic failure. It is also a prudent financial decision. The cost of a proper maintenance plan reduces the likelihood that you pay much more for an emergency fix.

You don’t want to have to replace your HVAC System every three or four years because you neglected maintenance and had a breakdown related to preventable wear and tear. A regular maintenance plan keeps your equipment lasting longer and reduces the likelihood you will need to buy a new HVAC system before you have gotten the most out of an older one. Besides, your family will breathe easier and better when you remove mould and dust from the air. Indoor air quality is particularly vital if anyone in your family has asthma or allergies. Here are some things you should regularly check and do to ensure your HVAC system is in good working order.

HVAC Preventive Maintenance Checklist

The kind of regular maintenance plan you need will depend on several factors:

  • Your particular type, brand and Model of HVAC system
  • The age and condition of the HVAC system
  • The size of your HVAC system
  • How much you use your HVAC system

Air Handling Units

  • In units with sprayed coils clean out algae and slime.
  • Inspect and clean outdoor air intakes and exhaust air discharges (outlets) where necessary
  • Inspect drain trays, ensure drains are clear, trays are clean, and drains have a water trap in them.
  • Check that appropriate indicating lights signify normal operation.
  • Simulate fire/smoke situation (for each system when separate) to effect changeover or shutdown as appropriate
  • Switch system back to ‘normal’ and check that all equipment is in the correct designated mode.
  • Check for leaks in coils and piping connections. Record and report any leaks.
  • Check panels, doors and fastenings for security. Record and report any leaks.
  • Ensure insulation is secure, record/report, as necessary.
  • Inspect flexible connections and record/report, as necessary.
  • Remove rubbish from conditioner housing.
  • Replace defective lights.
  • Inspect the casing for corrosion and leaks, record/report, as necessary.
  • During a fire mode test confirm the operation of all associated components of the system
  • The system performance criteria of zone smoke control systems should be verified between each zone.
  • Prepare and submit a signed original Fire Safety Certificate including, but not limited to Essential Safety Measures - Annual Specialist Maintenance Contractors Statement, other documents as required/requested.

Variable-Air-Volume (VAV) Units

  • Inspect VAV unit and components, and report on condition, and if cleaning is required. Clean away any loose material or obstructions to air flow.
  • Check function and operation of actuator through full cycle. Check all components, shafts linkages etc are secure.
  • Check all electrical connections for tightness or loose or damaged connections, or evidence of overheating. Report on condition
  • Inspect fans, fan motors and fan bearings for any signs of motor overheating, motor mounts bearing noise, cleanliness of fan wheel, amperage drawn and power supply (240VAC 50 Hz, 140VAC minimum in the case of speed control).
  • Inspect heating elements (where installed). If VAV has electric duct heaters, maintain in accordance with appropriate maintenance procedure
  • Inspect hot water coils (where installed) Check for water leaks.
  • Inspect chilled water coils (where installed) Check for water leaks.
  • Inspect primary air dampers. Check for free operation.
  • Check Velocity Sensor. Connect a manometer across the velocity sensor monitoring end connections, manually operate damper and observe changes in the readings to ensure the velocity sensor is not blocked (reading should be zero Pa only in fully closed position).

Fan Coil Units

  • Air intakes and exhaust outlets shall be inspected cleaned. Debris removed.
  • Fan Coil unit cooling / heating section, inspect coils, look for any unusual build-up of matter, inspect trays and sumps, and check condensate drains, tundishes, and traps checked for effectiveness.
  • Check for correct operation of the units / fans.
  • Check fan for undue noise and vibration. Where found to be excessive, investigate.
  • Check condition of motor and fan bearings for excessive vibration. Plan to replace as necessary, check fan / motor spring mounts for wear, adjust as required, grease bearings as per manufacturers recommendations, check flexible duct connections and mounting (main plant room fan), check drive belts tension and condition. Adjust as required, and, check alignment between motor and fan pulleys, adjust as required.
  • Check flexible duct connections, check spring mounts and mounting bolts for tightness, check couplings or pulleys for tightness and alignment and adjust as required, tighten loose nuts and bolts. Guards and fasteners to be made good. If missing report what is missing.
  • Check operation of all electrical controls, record motor amps and compare to name plate amps, inspect any electrical connections for looseness, tighten as required.
  • Check cooling coil drain for blockages - clean and flush as required. Top up traps if required and present, check condition of cooling / heating coils and clean as required.
  • Inspect dampers and linkages for correct operation, lubricate or adjust as required, check control valve actuation, stroke over full range of operation, tighten any loose connections to actuators. If found to be loose, tighten and check calibration, check damper motor mountings for looseness and condition of couplings, tighten as required.
  • Check / re-set calibration of any Magnehelic Gauges on unit.

Split and Reversed Cycle Air Conditioning Systems

  • Check casing, wiring and insulation for corrosion, clean, dry and that all components are secure. Record/report on any make good required
  • Check drains and drip tray are clear.
  • Check for unusual noise or vibration in the indoor unit.
  • Check unit operation through heating and cooling sequence.
  • Check for unusual noise or vibration in the outdoor unit.
  • Check compressor for oil leaks.
  • Check that condenser fan operates correctly.
  • Clean air filter
  • Check indoor coil for cleanliness.
  • Check outdoor coil for cleanliness.
  • Check operation of reversing valve.
  • Check that all controls operate correctly.
  • Check and record outdoor air temperature and air on/off temperature for both heating and cooling.

Packaged Air Conditioning Units

  • Check all components are secure.
  • Check drains and drip tray are clear.
  • Check insulation is secure.
  • Check operation through heating and cooling sequence.
  • Check refrigerant charge through site glass where fitted.
  • Inspect plant for physical damage and record/report on any make good required.
  • Lubricate in accordance with Manufacturer’s recommendation.
  • Record on/off coil temperatures.
  • Check and undertake minor adjustment of refrigerant charge if required. Record and report readings.
  • Check casing for corrosion, clean, dry and record/report on any make good required.
  • Check for broken frame supports or missing or loose bolts.
  • Check for icing on coil and investigate if necessary.
  • Check operation of defrost systems and devices.
  • Clean air cooled condenser coils, examine for damage, comb, as necessary.
  • Clean inlet side of evaporator coil if accessible.
  • Clean water cooled condensers, check for corrosion.
  • Fit set of gauges to refrigerant circuit, record readings.
  • Simulate loading of compressor. Check operation of control stages.

Evaporative Cooler

  • Check and adjust bleed rate
  • Check operation of float valve and dump valve
  • Check that pads are uniformly wet, adjust if necessary
  • Inspect pads for cleanliness, remove and hose down as necessary. Report if pads need replacing
  • Check drive belts
  • Switch on a check pump operation, drain and clean sump
  • Report if air filter requires replacing
  • Flush drainage system with clean fresh water
  • Inspect water strainer and clean where necessary
  • Adjust for even water distribution over filter pads
  • Check water bleed rate at 10 litres/hour for every 1000 litres/sec. Fan capacity or as otherwise recommended.
  • Inspect filter pads and record/report if new pads are required.
  • Reinstall drain plug in reservoir, fill reservoir and check ball valve setting, clean line strainer.
End of Season
  • Apply grease film to blower shaft and bearings.
  • Check belts for wear and adjust.
  • Check pulley alignment.
  • Clean water distribution channels.
  • Empty and clean water reservoir, leave drain plug out.
  • Examine for corrosion, repair as necessary and report if painting is required.
  • Lightly lubricate motor bearings to the manufacturers’ recommendation where possible.
  • Remove, hose down and reinstall filter panels.
  • Switch off pump, inside unit, if switch is fitted.
  • Turn off water supply.


Information provided in the text above is general in nature and does not consider your specific HVAC Preventative Maintenance needs and requirements. The information is not professional advice and should not be treated as such. You must not rely on the information in the text above as an alternative to professional advice. If you have specific questions relating to this subject, we strongly recommend that you seek independent professional HVAC Preventative Maintenance advice.