Air Handler Preventive Maintenance Checklist

HVAC equipment needs attention from time to time to prevent equipment breakdowns and to keep the equipment running at optimum efficiency. This includes air handlers also.

In many cases an air handler is made up of several components including the air handler cabinet itself, a blower to move air and a coil or possibly two coils. Some air handlers have controls inside of them especially light commercial and residential air handlers. A package unit will have all the components in one package including the air handler inside of it.

The air handler can be combined with a gas furnace or oil furnace in one unit. The air handler is usually attached to both the supply and return duct work and sometimes it houses the filters.

Air Handler Maintenance Checklist

It is important that the air handler (or air handlers if you own more than one) receive attention from time by a qualified HVAC technician. This means that you should have a regular maintenance schedule for your air handling unit (AHU) equipment.

The Air Handler Cabinet

The air handler cabinet is usually made of sheet metal and simply acts as a duct to guide the air through. It’s also to protect the air handler parts and components and to protect people from an hazardous air handler parts.

The color of Air Handler unit will depend on the manufacturer. Trane air handlers are usually color in green, Carrier air handlers are usually in gray, Goodman and York air handlers are usually in brown (as many brands use brown).

Commercial air handlers are usually unpainted sheet metal. Trane, Carrier and York paint their commercial equipment before shipping to customer. It simply depends on the manufacturer and what color they decided to use to paint their equipment before shipping.

Hopefully you can use this as a guide if there is no identifying information on the equipment. Sometimes the identifying information for air handlers are hidden on the inside of the cabinet but it is not recommended to open the air handler cabinet unless you are a trained HVAC professional.

The Air Handler Blower

All air handling units have a blower motor located inside the air handler cabinet.

Some air handing unit blowers are direct drive and some are belt driven. Many light commercial and residential blowers are direct driven by the motor while many commercial air handling units are belt driven by the blower motor.

Air Handler blower motors require regular maintenance in the form of oil or grease. All these blower motor/s, whether they are commercial or residential, have high voltage running to them which can be potentially dangerous. The other danger involved with checking these air handler blower motors is they are moving parts when energized and can cause serious injury.

It is recommended in commercial applications to replace the belts at least every ninety days. A qualified HVAC technician should perform this blower motor maintenance.

The Air Handler Coils

The air handler coils should be checked regularly for dirt and debris which may have been sucked into the air handler inadvertently.

Some air handlers have the filters inside them before the coils. It is a good time to change the filters when making this check. Any dirt or debris on the coil/s should be removed immediately as these things will impede air flow through the air handler and throughout the entire HVAC system as a whole.

A blocked air handler coil can also cause serious mechanical issues. The air filter should catch most of the dust and debris but it always good practice to check the air handler coils to be sure nothing is impeding air flow.

Some air handlers can have up to three coils inside them. These are usually commercial air handlers with a cooling coil, a hot water coil for heat, and a reheat coil for dehumidification purposes.

All coils should be inspected for any blockage including algae growth. Again, a qualified HVAC technician can handle all the air handler maintenance checks on your air handler coils safely and efficiently.

The Air Handler Control Panel

The air handler control panel has a lot of electrical components inside it. Electricity can be very hazardous so it is recommended that a qualified HVAC technician perform the air handler maintenance checks on the air handling unit control components.

The air handling unit maintenance checklist on an air handler control panel comprise of looking for loose connection with wiring, loose line voltage connections, burned or corroded wiring and connections, pitted or scared contacts on contactors and relays, and take amperage readings on the main air handler components to make sure there is normal operation.

Capacitors can also be tested to make sure they are within the proper ratings as specified by the manufacturer. These entire tests or your air handling unit(s) should be performed by a qualified HVAC Technician.

Professional Air Handler Maintenance

Here’s what you can expect from professional HVAC technician do at your air handler maintenance and service:

  • Clean the coils.
  • Check for leaks. All coils, refrigerant lines, valves, fittings, etc.
  • Check for rust in condensation pans and drains.
  • Check all belts for signs of wear and cracks.
  • Clear dampers of dirt accumulations.
  • Make sure fan blades are free of dust buildup.
  • Ensure all moving parts are free of cracks and excessive wear.
  • Test fan RPM so it meets design specifications.
  • Tighten Bearing collar set screws on fan shaft.
  • Confirm damper actuators and linkages are operational and aligned.
  • Confirm all mechanical connections and dampers are properly lubricated.
  • Properly align rigid couplings.
  • Drain and remove any moisture from all cooling coils.
  • Make sure freeze stat is on proper temperature setting and operation.
  • Vacuum the entire unit properly.

Just like anything else, when you keep HVAC system in good condition, it will last longer and issues can be addressed before they become major problems. These basic Air Handler maintenance checklist can save you money on your HVAC energy budget, save you discomfort from unexpected air handler breakdowns, and add longevity to the air handling unit equipment for years to come.

While some Air Handler maintenance can be done DIY, it’s still necessary to have a professional HVAC technician to check the entire system periodically.

About Mas Broto

Have been in the heating and air conditioning (HVAC) industry for over 20 years. He is person that will grow and thrive to learn more about the HVAC industry throughout his career. Mas Broto is also a blogger, who's dedicated to bringing you the best knowledge to get ahead in the game of life.