Do It Yourself HVAC Maintenance: A How To Guide

Many people tell me “Rob, I know how to do a lot; plumbing, a little electrical, I can work on my car, but I have no idea how to work on my air conditioner!” So, they ask me what they can do, and I tell them that the best maintenance they can do is preventative maintenance.

When I use the phrase “preventative maintenance,” I can’t help but to think back to my Army days. As a Cavalryman, every Monday was “Motor Pool Monday!” On Motor Pool Monday, after physical exercise, we would go to the motor pool to conduct preventative maintenance on our vehicles. The idea was to find issues caused by everyday normal wear-and-tear and repair them before they become major issues that sidelines a vehicle and reduces a units combat effectiveness.

It is with that goal that I address the issue for homeowners. There are many things a conscientious home owner can do that will increase the life of their equipment, and minimize the potential for costly repairs. Here are the things that I recommend:

  1. Change your filter as needed! Additionally, you do not need to by an expensive filter, and in fact I recommend for the longevity of your equipment that you do not buy an expensive filter, unless of course you have allergies. People think about their air filter all wrong – the air filters purpose is not to clean the air you breath – it’s to keep your blower motor protected and clean. A clogged air filter can and will result in a system failure.
  2. Turn the AC off when cutting your grass. Have you ever placed your hand just over the fan of your air conditioner? If you have you’d notice that the fan is blowing the air up and pushing it out the top of the air conditioner. That creates a vacuum-like effect on the coils below. If you’re cutting your grass while the air conditioner is running, your air conditioners coils will suck up the grass clippings and other debris that result from cutting your grass. When your coil becomes clogged with debris like grass clippings, it prevents the AC from properly transferring the heat from inside the house to the outside.
  3. If you notice your AC becoming a little dirty hose it down. Of course, make sure the air conditioner is off when you do this; unless you’re the kind of person who just enjoys spitting into the wind.
  4. Have a modern thermostat installed. Why? I’ll tell ya – compressors. Every air conditioner / heat pump has a compressor. Compressors are fickle things that need to be protected from misuse. Imagine you can work your air conditioner with a light switch. You flick the switch and your air conditioner turns on! But, imagine you flick the switch again turning off the air conditioner, and then you flip it right back on. What can happen is that the air conditioners turns on, except for the compressor. Compressor’s do not behave correctly when this happens to them, and what can result is that compressor will overheat from receiving electricity while it’s not running. Why do compressors do this? To explain this very scientific phenomena I will utilize a very scientific quote for, Joe Dirt:

Hey! How exactly is a rainbow made? How exactly does a sun set? How exactly does a posi-trac rear-end on a Plymouth work? It just does.”


So, now that we walked you through the science of it all, a modern thermostat is the solution to the potential problem! Why? Modern thermostats have time delays built in. Typically, most are set at 5 minutes. This prevents the compressor from being quickly turned on and off which prevents the conditions above from manifesting.

  1. Have it professionally serviced twice a year! An air conditioner is an appliance that needs to be treated like a vehicle when it comes to maintenance. Air conditioners have many moving parts and electrical components that are extremely dangerous which is why we do not recommend untrained people take any further action than the 4 do-it-yourself maintenance tips listed above. Having your unit serviced will ensure that your units capacitors (more science stuff) are at full strength and not putting additional strain on your expensive motors and compressor. A service will ensure that your refrigerant level is where it needs to be – if your air conditioner is a tad low on freon you will pay for it in your energy bills over the summer. And during the winter time, a service will ensure that your gas furnace is not leaking carbon monoxide and that the gas combustion is working safely and properly.


In closing, the first four steps are very important, and if followed, will increase the life of your equipment. But at the end of the day, I still recommend a professional, bi-annual, service be done. The cost of professional maintenance can easily outweigh the costs of not having it done. It is proven (though I can’t source this fact with a Joe Dirt quote) that air conditioners that are regularly serviced last longer and run more efficiently.