The HVAC industry is booming with a 6.3% CAGR because many people are incorporating HVAC systems in their houses and commercial buildings to make their interiors more comfortable.

This heating and cooling system is like a car. It works properly only if regular maintenance is carried out.

Also, regular maintenance helps your system produce and distribute the cool or warm air evenly at a steady pace into the building.

To be precise, seasonal changes affect the system’s functioning to a great extent. If you don’t maintain the system, the harsh winter can freeze the HVAC components, and the hot summer might damage them.

So as an HVAC technician, your work isn’t over after installing an HVAC system, rather, you must maintain it well and educate the customers about the same.

This article has a checklist for HVAC system maintenance for different seasons. Now let’s get started. 

What is HVAC System Maintenance?

If the HVAC system must work properly and keep the house’s interior and office building snug or cool for many years to come, then HVAC maintenance is the prerequisite to make it possible. 

HVAC maintenance is a visual inspection of the entire HVAC system semi-annually or annually for signs of defects and the cleaning, repairing, or replacing of parts on the system. 

Some benefits of keeping the HVAC system in the best condition are:

Reduce the utility bills

A well-maintained HVAC unit will operate efficiently provided the building is insulated correctly. So this will positively reflect on money spent on electricity, heating and cooling costs. 

Regular maintenance of the HVAC systems can lower energy bills and the major need for repairs or replacements.

Improve the air quality

If the filters and coils aren’t cleaned, the quality of air is at stake. So to ensure your customers breathe fresh, quality air, maintenance is important. 

Increase the HVAC’s lifespan

As an HVAC technician, you must have made some extra effort to install the entire system properly so that your customers can taste comfort in their house and want to ensure it lasts longer, isn’t it?

The more the heating and cooling unit is maintained, the more it can increase its lifespan.

Clogged drain pipes and water leaks

If you find puddles of water near the heating and cooling unit, you can strongly confirm it’s the byproduct of heating and cooling the air by the HVAC unit. However, the drain pipes will move the condensate water automatically. If they didn’t, then it’s clogged. 

Other symptoms of these clogging problems are musty odors and leaks. Clogged pipes can be cleaned with a small brush or pipe cleaner, and replace the drain pipes if they leak. If maintenance is done frequently, these clogging problems can be avoided. 

Thermostat issues

Even the best and most expensive thermostats can malfunction after some time. So to avoid trouble and maintain the right temperature in your home, it is recommended to get it inspected.

A Complete Checklist For HVAC System Maintenance 

Below you will find separate checklists for different seasons. Because each season can affect the HVAC system differently and thus needs specialized treatments. For instance, the furnace works hard during winter to deliver heat. Meanwhile, the air conditioner works harder during summer.

HVAC Maintenance Checklist for Hot Seasons

The temperatures heat up in May, June, and July. So to beat the hot summer, most people rely on HVAC systems to keep the indoor spaces comfortable and cool. About 84% of homes in the United States have some type of air conditioning. However, the summer season causes trouble to the HVAC systems and affects their overall functioning. 

The main part which gets affected fast is the AC units. Because the capacitor keeps the motor running and they are vulnerable to overheating. Especially if it runs for a long period, there are other parts that get damaged or demand repair during summer. So here is a quick checklist for preventative maintenance to be carried out this season. 

Spring/summer HVAC preventive maintenance checklist

  • Clean condenser and evaporator coils
  • Clean or replace all filters
  • Check drain pans for standing water and clear them to avoid overflows
  • Clean drain lines for proper flow and clear clogs
  • Replace pulleys and belts if they are worn out
  • Inspect ducts for dust, mold, and debris
  • Observe the humidity levels in and around the HVAC system
  • Check refrigerant charge and for leaks
  • Inspect the thermostats and controls to ensure the temperatures and timer functions are in check
  • Change batteries if needed
  • Check electrical system and connections
  • Check the fan motor if it’s operating correctly
  • Check blowers and inspect fan blades for proper airflow
  • Lubricate motors bearings and other moving parts
  • Check if there are leaks in the cabinet and check cabinet door if it is closed safely.
  • Check for dust or debris around the outdoor unit.

HVAC Maintenance Checklist For Cold Seasons

Harsh winters are not only harmful to living beings but also to non-living things. The HVAC system, despite its quality, will not sustain harsh winters without proper maintenance. 

The water inside the coils and lines can freeze in minus temperatures. The worst part? Water expands when it freezes and when this happens, the line or coil will burst.  So below, we have given the HVAC maintenance tasks for the winter season. 

Autumn/Winter HVAC preventive maintenance checklist

  • Replace filters on the HVAC system’s heating equipment
  • Check the ignition burner assembly
  • Examine the HVAC system’s heat exchanger or heating elements 
  • Inspect the flue system and check the secure attachment to the furnace
  • Inspect for gas leaks with gas furnaces
  • Assess the gas pressure
  • Check belts and pulleys
  • Check and clean drain lines and pans
  • Check all the electrical connections
  • Lubricate motors, bearings, and other moving parts
  • Check thermostats and controls
  • Check fan and blower operations and adjust as needed
  • Examine ductwork and vents
  • Inspect heat pump

Common HVAC Problems That Can Be Avoided With Regular Maintenance

1. Dirty filters

If your customer is complaining that their HVAC system isn’t circulating enough air inside the building, it’s probably because their air filters aren’t replaced regularly. 

If the air filters are clogged, air can’t pass through them. So clogged filters stop the air from cooling and heating. It damages your HVAC system and negatively impacts the energy bill. 

Also, a dirty filter makes the furnace overheat and shut off at a high limit. 

2. Dirty coils

Like filters, the evaporator coil of the heat pump or air conditioner in the HVAC system can get dirty. When they get dirty, their efficiency goes south by a significant amount. 

If the dirty evaporator coil of the heat pump is placed as an external unit, then it can simply be hosed off. But if it is an indoor unit, you must carefully clean the coils. 

3. Refrigerant leaks

One of the common reasons for customers to call HVAC service is when their air conditioning unit doesn’t work.

As an HVAC technician, you know the reason, right? Refrigerant leaks. 

The lifeblood of the air conditioning unit in the HVAC system is refrigerant. If there is a refrigerant shortage, probably, the AC unit won’t work. This refrigerant leak is caused due to multiple things. 

One common reason is corrosion. If the system’s coils, loose fittings, and holes in the refrigerant pipes have corrosion, then they cause leaks. To prevent this, regular checks must be done on the HVAC units. 

4. Tripping circuit breakers

Some circuit breakers must be reset regularly, so ensure you check this. Also, if the HVAC system works too hard, it can result in a dirty air filter or even a more complex problem. So, it is recommended to check and maintain the circuit breakers. 

5. Blower motor running excessively

Is the customer complaining the blower motor is running excessively? Then, the thermostat must be checked first. The furnace’s blower motor will run excessively due to a defective relay. So during maintenance, remember to check if it’s working fine or needs repair. 

6. Pilot light fails to ignite

Heating systems that rely on gas or propane need a pilot light to ignite them properly. Some HVAC systems have a pilot light running constantly. Meanwhile, some pilot lights will turn on when the system starts. So if the light isn’t turning on, the flame sensor may be damaged or dirty. Thus, while preventive maintenance check, you must clean the sensor and ensure proper working.  

7. Mechanical wear and tear

The HVAC system relies on multiple mechanical components. Naturally, no matter how strong or of good material they are made, they face wear  and tear. So, the unit’s performance will be impacted by this wear and tear. Also, it leads to overheating, poor heating, or airflow issues. So during maintenance, the HVAC system must be inspected for worn or stretched belts and oiledbearings and motors. 

8. Furnace noises

Furnace noises are part of the normal operation, but unusual noises aren’t. They might be a warning or indication of a mechanical problem. A whining or squealing motor indicates that the bearings either in the blower motor or inducer motor are failing. So without ignoring these signs, it is important to check them once. Otherwise, it can lead to a furnace failure.

Frequently Asked Questions

What should be included in HVAC maintenance?

Be it a hot season or cold season, HVAC maintenance for either season must include the following:

  • Thorough cleaning of drains, coils, and elements
  • Inspecting motor operations, connections, and thermostat functionality
  • Monitoring refrigerant pressure
  • Testing all the safety controls
  • Lubricating the moving parts

What needs to be changed in HVAC system regularly?

The air conditioner in the HVAC system must be changed regularly. Because this part plays a major role in providing good indoor air quality. If the AC unit gets damaged or if you notice mildew, dust, mold, or other issues, then it must be repaired or replaced soon.

What are the four different phases of planned maintenance for HVAC?

There are four different phases of planned maintenance for the HVAC system; they are:

  • Corrective maintenance
  • Preventive maintenance
  • Predictive maintenance
  • Risk-based maintenance

What is HVAC preventive maintenance?

Preventive maintenance is the act of performing regularly scheduled maintenance activities to avoid surprise breakdowns and keep the HVAC system running all season without any issues. So, HVAC systems must undergo preventive maintenance to prevent unnecessary issues from popping up in the HVAC system.

How often should HVAC system maintenance be performed?

It is recommended to carry out HVAC preventive maintenance atleast once a year despite the type installed. Apart from maintenance, the system must be inspected, cleaned, serviced, or replaced if necessary. The interesting part of the maintenance is that you can get the heating system checked in the fall and the air conditioning unit during spring.

What factors do a regular HVAC maintenance plan depend on?

The regular maintenance plan will depend on several factors, such as the HVAC system’s age, condition, size, and brand. Also, how much the HVAC system is used and the location of the building matter.


To have a healthy operating HVAC system, regular inspections are inevitable. The HVAC system will be affected adversely with time and based on different seasons.

Many things can go wrong with the HVAC system that happens more often than you would think as an HVAC technician. There are solutions, whether small or big issues or problems! But if there is anything to avoid these unnecessary problems, then maintenance is the best answer. 

Your customers with an HVAC system may not be aware of the importance of maintenance. But as a responsible HVAC contractor or technician, it is your job to highlight these things. 

You can also sign scheduled HVAC preventive maintenance, saving your customer’s money in the long run. By educating your customers, you can win business and save them money. It’s a win-win for both. 

We hope the HVAC system maintenance checklist for four different seasons was of some use. As an HVAC business person, you must not miss out on any.