The “If You Can, Then You Can” of Residential HVAC Maintenance
Rest assured, maintaining the majority of your HVAC unit does not require serious technical know-how. If you are capable of washing a car, you can perform 70 percent of the work required to maintain a residential HVAC unit. Do you change the oil in a car? If so, you can do 80 percent of the maintenance work on an HVAC unit too. You can do 95% of the maintenance if you’ve ever changed a car battery without setting off sparks.
In addition to requiring very little know-how, HVAC maintenance doesn’t require specialized or tools and instruments either.
If you own a toolbox and it doesn’t say “Play-Doh” on the side, you probably have what you need to do your own HVAC maintenance. You can do half your HVAC maintenance with a Phillips, a broom handle, a shop towel, and a hose.
If you are still not certain you have what it takes to do it yourself, the following checklist will give you a better idea of what is required.
Take note that at the end of the checklist, there are three don’t-do-it-yourself maintenance/repair scenarios. The title of the section is, “If You Run Into One of These Problems, Call an HVAC Professional.” It’s there so you don’t have any, “Oh $#!%. I shouldn’t have tried that” moments while doing your HVAC maintenance.
If you run into one of the problems/symptoms listed under the section below titled “If You Run Into One of These Problems, Call an HVAC Professional,” call an HVAC professional. Even if you are an astronaut who does his own rocket science, there are some HVAC repairs you should leave to an HVAC professional.
The Basic Parts of an HVAC System
An HVAC system is also known as an air distribution system or a central air conditioning unit.
The HVAC system in your home is responsible for regulating the ambient air temperature, filtering the air, monitoring, and adjusting humidity levels. There are really only two parts to an HVAC system: duct networks (inlet and exhaust) and an air handling unit.
The two parts of an HVAC system have subcomponents. The duct networks include filters.
The air handling unit includes:
- Furnace (Including the Thermostat, Heat Exchanger, Burners, etc.
- Condensing Unit (Including Evaporating Coil and Refrigerant Lines)
Basic Residential HVAC Maintenance Checklist of 3 Items
Every year, you should do general maintenance on your HVAC system. And, every maintenance measure should serve a specific purpose. Your primary goal with respect to maintenance should be to improve air quality.
1. Filter Maintenance/Replacement: Improving the Air Quality in Your Home
The first step to improving the air quality in your home is HVAC filter maintenance. You have two options. You can clean the reusable filters in your HVAC system or you can replace the disposable filters. But first, you have to find them!
How to Find HVAC Filters in Your Home
Because there are different kinds of HVAC systems — and a house may have more than one HVAC unit — the filters are not always in the same place.
But, there are really only three places you will find air filters in an HVAC system:
- Behind the return air grills – You might find return air grills up high on a wall near the ceiling. If they’re not there, you might find them down low near the baseboards. Or, the return grill may be located on the ceiling.
- The filters behind the return air grills aren’t the only ones in the house. You will also find filters in the HVAC air handler. There are two kinds of air handlers: horizontal air handlers and vertical air handlers. Vertical air handlers are generally smaller units, so they fit into smaller spaces.
There are two kinds of vertical air handlers.
Upflow vertical HVAC air handlers.
The air filter is generally found on the bottom of an up-flow vertical air handler.
Downflow vertical HVAC air handlers.
The filter is usually found on top of a down-flow air handler.
Horizontal units include industrial-sized air handlers. Sometimes, the filter can be found on the back of the unit, but the filter is usually in a filter-housing slot, on the side of a horizontal air handler. However, the filter is usually in a filter-housing slot on the side of a horizontal air handler.
How to Clean HVAC Filters in Your Home
Cleaning filters is as simple as running water over them. The key to cleaning an HVAC filter is making certain that you spray the filter in the opposite direction that the air flows through it. If you haven’t cleaned the filter in a while, one side will be dusty and dirty. The other side will be noticeably cleaner.
Spray the clean side to knock the filth off the other side.
Let the filter air-dry completely before putting it back in place.
If you have cleaned the filters several times, it’s probably best to replace them. That means about once a year because you should clean the HVAC filters in your home every two to four months. Sometimes, however, you will need to replace the filters more often.
If your filters are extremely dirty and you can’t seem to get them clean by spraying them with water, replace them. If your HVAC unit has dirty filters, it is not only recycling air, it is recycling dust and micro-particles. Dust and micro-particles in the air in your home can lead to everything from allergies to asthma and even more serious respiratory problems.
Disposable vs Reusable Air Filters
The argument for reusable air filters is that they are, as the name implies, reusable. While they may be slightly more expensive than disposable filters initially, reusable filters may save you money in the long run.
However, reusable filters typically have a lower Minimum Efficiency Reporting Value (MERV) rating than disposable filters. A quality reusable filter will only have the capacity to capture 75 percent of the dust, pollen, microfibers, and organics that pass through.
A typical disposable air filter, on the other hand, will capture 95 percent of aerial debris, or greater.
2. Maintaining Your HVAC Furnace
The idea of doing your own HVAC furnace maintenance may sound like a tricky proposition, but it isn’t.
There are a large number of things you can do to maintain the furnace without disassembling the mechanical and electrical parts. Most of it entails inspection and cleaning.
***The one thing to remember is that most of them are powered with natural gas or propane. Always shut off the gas line before inspecting or maintaining an HVAC furnace.***
The parts of an HVAC furnace you can inspect and clean yourself are the:
Heat Exchanger – Look for cracks on the body and around the couplings of the heat exchanger. When they begin to get older, most of them crack.
Burners – The burners on an HVAC furnace tend to get dirty. Removing them is simple and you can clean them with a damp towel.
Pilots – Clean and inspect the pilot and pilot assembly. Use a non-flammable degreasing agent and wipe them clean when you are finished.
Gas Lines – Cracked gas lines are the only truly dangerous components of an HVAC system. Visually inspect the lines. Look for cracks, dents, and abrasions. And, get your nose down near the line and smell for gas. Make sure all couplings are in good condition as well.
Belts and Pulleys – Inspect the belts and pulleys and make sure they are not cracked, that they have adequate tension and that they are not frayed.
3. HVAC Air Conditioning Unit (Condensing Unit) Maintenance
Unlike a furnace, an air conditioning unit is generally electrically powered. That does not mean they do not have the potential to be dangerous. Most run on 220 voltage. It just means there isn’t the potential for an explosion.
Always flip the breaker to the air conditioning unit prior to performing maintenance on an HVAC air conditioning unit prior to performing maintenance. Not only are you protecting yourself from the potential of an electric shock, but you can also be certain that the fan will not kick into gear while you are maintaining the unit.
The primary purpose of cleaning an air conditioning unit is to remove dust, leaves, grass, and other debris that might be restricting airflow into the unit.
There are two parts of a condensing unit you want to focus on maintaining:
1. Condensing Coils.
How to Clean the Coils of and HVAC Condensing Unit
The condensing coils on an HVAC unit are sometimes called the “grill.” The coils are the thin, flat wires running around the outside of a condensing unit. A mesh-wire coil guard holds the coils in place.
You can use a broom as well as a soft bristle brush to clean the coils of an HVAC condensing unit.
Be careful, however, not to bend the coils. They are easy to damage. Use very gentle pressure. And, always run parallel to the coils when cleaning them, never perpendicular.
How Clean the Fan on an HVAC Condensing Unit.
By removing the lid on the top of the condensing unit, you can access the fan. With a damp towel, you can clean both the fan fins as well as the housing of the motor.
Once you’ve removed the lid from the condensing unit housing, you can then clean the coils from the inside of the housing.
Do not remove the fan nor attempt to disconnect the wiring. If you do, you run the risk of remounting it at an angle, an error that can damage the fins, the condenser housing, and the fan motor.
Those are the Basics of a Residential HVAC Maintenance Checklist
By replacing the filters; inspecting and cleaning the furnace, and maintaining the air conditioning unit, you can keep your HVAC system running efficiently. And, you can prevent system failures.
There are, however, a number of HVAC problems and symptoms you should leave to professionals.
If You Run Into One of These Problems, Call an HVAC Professional
There are two circumstances in which you should not try to maintain your HVAC system. If you believe you might be putting yourself in danger, call an HVAC professional.
An instance in which you should not do the maintenance yourself is upon the discovery of a gas leak in or around the furnace unit. Call your HVAC professional immediately. If the leak is severe, please call your local gas company or dial 911. Make sure you open a window if the leak is inside the house. Keep in mind that a gas leak is considered an emergency because it can cause an explosion.
Another situation you want no part of is exposed to electric cables in a condensing unit. If you find exposed cables, again, call your HVAC professional.
Less serious HVAC system issues that you still probably do not want to deal with include:
- Motor blower voltage and amp adjustments.
- Thermostat calibrations.
- Motor and bearing lubrication.
- Flue pipe corrosion and leaks.
- Fan motor maintenance.
- Cleaning duct systems.
The residential HVAC maintenance checklist above will help you keep your system in order. It is important to remember, however, HVAC professionals perform all of the maintenance listed above — and more — professionally. Don’t hesitate to call for help!