(707) 800-6287 |  Sonoma Napa and Marin Counties

updated Jan. 2023

The heating and cooling equipment that keeps your home or business comfortable throughout the year is like any other machine — it can wear out and break down over time, especially if it isn’t well maintained. It is all too easy to take important items of maintenance for granted when your system works. When things break down, though, many often find themselves wishing they’d done something to prevent the problem in the first place. By knowing and sticking to an HVAC maintenance checklist, you can do everything you can to keep your equipment operating near peak condition.

What should go on your maintenance checklist? The items which follow include a mix of tasks you can and should regularly undertake on your own, along with maintenance items that require a more experienced team to tackle. Not sure what some of the terms below mean, or what the different parts of an air conditioner are? Take some time to learn about those things first, then start putting together a checklist like the one here.

HVAC 101 Everything you need to know

Guide to HVAC Maintenance

A working HVAC system is a necessity for most of us, especially in places like Santa Rosa where the weather reaches uncomfortable temperatures throughout the year. After all, who wants to sweat all summer or shiver all winter? For most people, spending a few thousand dollars on an HVAC installation feels like it should be enough, but that’s not the case. If you’re not careful about maintaining your newly-installed system, you could find yourself facing pricey repair bills or even a replacement unit years before it should be necessary. Luckily, standard HVAC maintenance is pretty easy and straightforward, so you can handle most of it by yourself. Not sure where to start? This blog post covers the most vital points on any HVAC maintenance checklist, so by the time you’re done reading, you’ll have all the information you need to keep your air conditioner or furnace running for a decade or more.

Change Your Filters on a Regular Schedule

Caucasian Hands holding black pen and checking list on white paperIt is one of the most often repeated pieces of advice, but your air filter is your first line of defense for your HVAC system. Not only does it help to safeguard the quality of the air you breathe by trapping allergens, but it helps to keep excessive amounts of dust from accumulating on important components in your system. Monthly changes are ideal, though some modern filters feature a design intended to last for up to 90 days. Visually inspect your filters once a month and don’t go too long between changes.

Clean or Replace Your Air Filters 

Your air conditioner or furnace’s air filter is tucked away inside the unit so it’s easy to forget about it, but this is actually one of the most important things you can do to keep your HVAC system running smoothly all year. The filter prevents dust, dirt, pet hair, and any other contaminants from entering your air supply, improving the air quality in your home and protecting you and your family from allergies, asthma symptoms, and other potential medical issues. Air conditioners don’t actually bring any new air into your home from outside, they just cycle the same air through the system over and over, which means a good air filter will actually be cleaning and purifying the air whenever the HVAC system is running.

However, if you allow the unit’s air filter to become dirty or clogged, it can have a few different negative effects on the HVAC system. First, it can actually make the filter itself less effective, as the clog can force small particles of dust or dirt through the mesh into the air in your ducts. More importantly, it severely cuts down on the airflow through your HVAC system. All air has to go through the filter before it enters the ducts, which makes it a bit of a bottleneck. When the filter is partially blocked, the air gets trapped behind the clog and airflow is reduced, sometimes severely. Not only will this make the system less effective at controlling the temperature in your home, but it also causes problems for the unit itself. When airflow is reduced, the system has to work harder to make up for the loss in efficiency. It switches on more frequently and stays on for longer, which can cause a spike in your power bills as well as increase the wear and tear on the parts inside the unit. Failing to clean or swap out the filter on a regular basis can leave you with some expensive repair bills when something finally breaks.

There are a few different types of HVAC air filters. Some of them are disposable and need to be replaced every so often, while others can be washed with soap and water and returned to the unit. If you have a reusable filter, make sure to let it try completely before you put it back in the housing – otherwise, the leftover moisture can cause mold to grow. The documentation that came with your air conditioner or furnace should tell you what kind of filter to buy, and the packaging of the filter will let you know how often it needs to be cleaned or replaced – usually about once a month or so.

Prevent Dust from Building Up in Key Spots

Your filter will keep a good deal of dust out of your system, but it can still build up in areas it shouldn’t. For example, if your air handler unit is inside of a closet or your return duct and filter are behind a grate, you should clean these spaces frequently. Large amounts of dust will tend to accumulate in these areas. It is both unsightly and undesirable, as it increases the chance for dust infiltration into your ducts. 

Prevent Dust from Building Up

While the air filter does a pretty spectacular job at keeping dust out of the air, it can still accumulate elsewhere in the system if you’re not careful. The most common place for dust to build up is on the vent covers that allow air to escape the ducts into the house itself. There are two main types of vent covers that are commonly used in HVAC systems: grills and registers. Grills are the simple metal covers that you see on most vents. They have a series of small slits that allow air to escape while preventing anything else from entering the ducts. While these slits are perfect for trapping debris before it enters your ductwork, dirt and dust tend to accumulate on them, blocking airflow into the room. Luckily, cleaning grills is pretty straightforward – you generally just have to brush them with a feather duster or use a nozzle attachment on your vacuum cleaner to collect the trapped dust.

Registers are a lot like regular grills, but they also include dampers that allow you to close off access to the ducts. Dampers are great if you want more control over the temperature in each room, but they can be a bit more difficult to clean since they’re generally on the duct side of the register. If dust or grime gets caught up in the dampers, you might have to unscrew the register and take it off entirely before you can clean it. If you think your grills or registers are getting especially dirty, you can always just give them a quick scrub in the sink with water and soap. Just remember to let them dry before putting them back up.

The unit itself can also collect dust and will need to be cleaned occasionally. An HVAC technician can handle this for you during your regular service appointments, but it’s also easy enough to take the cover off an air conditioner and give it a gentle clean yourself. The blower fan is especially adept at gathering dust, so make sure you check it first. While the coils don’t tend to collect much dirt, even a little bit of grime can affect the efficiency of the unit or even cause ice to build up inside. If you do decide to clean off the coils by yourself, be very very careful – the metal fins are extremely delicate and easy to accidentally bend, and a new coil will cost you upwards of $1,000.

Keep the Outside Unit Clean

Most residential air conditioners are split-system, which means they have one unit that goes inside your house and one that goes outside. While the outside unit is generally pretty hardy, it still requires a little attention every once in a while. When the inside unit pulls heat out of the air in your house, that heat is transferred over to the outside unit, where it’s released into the air outdoors as exhaust. If the exhaust grills on the outdoor unit are blocked or covered up, all that hot air can get stuck inside the unit, causing the compressor motor to overheat. If you don’t clear away leaves, dirt, and other debris from the casing of the unit, you could end up spending $2,000 or more on a replacement compressor.

Since the outside units are tougher than the inside ones, you can usually clean off any debris just by spraying it down with a hose. Anything that gets stuck in the grills can be cleaned off with a cloth afterward, and you can clean off the inside of the unit by taking the casing off, although you can also just leave that to the professionals during your yearly service appointments. The best way to keep debris from getting caught up in the AC unit is to be careful about where you place it. Keeping it away from overhanging trees is a big help, as is leaving a little space between the unit and any nearby bushes. Some people choose to just put up some simple wooden fences around the unit to keep everything out, but make sure you leave enough space for a technician to get in there and service it.

The most dangerous time for the outdoor unit is actually during the winter when it’s not being used. Snow and rain can cause moisture to build up inside, and any debris that gets caught in there usually isn’t cleaned up until the spring or summer. We recommend covering up the outdoor unit with an AC cover during the winter, especially if you live somewhere with a lot of snow. These covers are breathable enough to let moisture escape, giving them an advantage over a tarp, which would trap moisture inside and encourage mold to grow. Alternatively, if your unit has grills on the top, you can just cover them up with some waterproof deck wood and hold it down with a brick as a more cost-effective alternative to the cover.

Keep Leaves and Plant Debris Away from Your Outdoor Unit

Observe the location of the outdoor unit for your air conditioner. Is it near bushes, hedges, or trees? It’s not uncommon for this unit to end up near some landscaping features due to a lack of available space. About once a month, head outside and clear off the area around this unit. Keep leaves from accumulating on top of the unit or around it, as this could affect efficiency and put too much strain on your compressor. Trim back tree branches to reduce the risk of damage to your equipment should one break.

Dust Mites in your HVAC Ducts

Maintain Your Thermostat As Well

As HVAC contractors, one of the most common complaints we get is a blank thermostat. While we’re more than happy to head over and help, often times the trip (and subsequent bill) could have been avoided with a simple change of batteries. Most thermostats take regular everyday AA or AAA batteries, and swapping them out should be the first thing you do if you notice that the screen is blank. If you switch the batteries and the thermostat still won’t turn on, then you might have a more serious problem.

Thermostats sometimes have to be cleaned as well. Giving the inside of your thermostat a quick cleaning can be a simple fix if you think the calibration of the temperature sensors is off. You can actually test this yourself by taping a glass bulb thermometer on the wall next to the thermostat. Make sure you put a little cloth or a paper towel between the glass and the wall to make sure it’s just measuring the temperature of the air. Wait about 15 minutes and then return to check the readings. If the temperature reading on the thermostat is more than one degree away from the bulb thermometer, then you might need to give it a cleaning.

You can clean your thermostat by taking the faceplate off to expose the wiring inside. The wires and instruments inside are fairly delicate, so clean away the dust by gently blowing it off the circuit board. Make sure not to use a vacuum cleaner since the suction is too high and could damage the thermostat. If you see dust trapped between any contact points, be very careful when you clean it off. Here’s an old HVAC technician’s trick: the best tool for gently cleaning dust away from these contact points is actually a fresh dollar bill, which is just rough enough to catch the dust without scraping at the electronics. If your thermostat has a mercury vial inside, use a level to make sure it’s perfectly even. If not, take the thermostat off the wall and put it back up so the vial is level. If you clean the thermostat but the temperature is still off, you should probably just pick up a new one.

Keep Fresh Batteries in Your Thermostat

Did you know that blank thermostats are one of the most common complaints HVAC maintenance teams hear? It’s a frustrating problem that sometimes indicates a more serious problem with your installation, but most often means that the batteries powering it have run out of charge. Changing the batteries in your thermostat should be easy; follow the instructions provided by the manufacturer. Most modern thermostats will display a low battery warning to let you know when it’s time for a swap.

Residential heating

Keep Up With a Professional Service Schedule

We’ve alluded to this a couple of times already, but it’s generally not enough to just keep your HVAC system clean throughout the year. If you want to avoid repair bills and other costs down the road, you should really get each unit a tune-up once a year or so. These maintenance service appointments might seem like an unnecessary expense, but they can go a long way toward extending the lifespan of your HVAC units and preventing expensive repairs. A professional HVAC technician will be able to spot things that you most likely won’t notice on your own and make sure they don’t become bigger problems later.

During a service appointment, an HVAC technician will give your furnace or air conditioner a full cleaning, both inside and out. That includes all the small delicate parts that you might not want to clean by yourself, even down to the bearings inside the motor for the blower fan. They’ll also inspect every part as they’re cleaning it to make sure that wear and tear isn’t causing any potential issues already. When servicing a furnace, they’ll check and double-check all the safety features that prevent gas leaks so you can rest assured that your family is safe. During an air conditioner service appointment, a technician will also flush out the refrigerant lines, check for leaks, and replace any refrigerant that’s been lost over the past year.

Generally, it’s a good idea to have your HVAC appliances serviced shortly before the beginning of the heavy-use season. For air conditioners, that means calling a technician in early to mid spring, and furnaces should be serviced in the fall before the weather gets too cold. One way to make sure you stick to the schedule is to sign up for a service contract. For a single fee, a service contract will get you free maintenance appointments, free labor on repairs, and often a discount on any replacement parts your HVAC system might require. You’d have to do the math yourself to decide if a maintenance contract is worth the money, but it frequently can be. Typically, signing a service contract also means the repair company will handle all the scheduling for you, which can be a relief for anyone who frequently loses track of these things.

An Annual Service Visit is a Must

While there are plenty of things you can do at home, there’s no substitute for a professional’s assistance. Once a year, call for preventative maintenance and an inspection from an HVAC team you trust. During this visit, your technicians will carry out a variety of tasks which may include:

  • Removing dust from interior system components, cleaning the compressor, and checking refrigerant levels
  • Replacing worn-out components and inspecting for signs of damage or excessive wear
  • Draining and cleaning condensation pans
  • Assessing the age, efficiency, and likely remaining lifespan of the unit

Don’t try to do these jobs yourself — turn to a team with the right tools and experience as a part of your HVAC maintenance checklist.

Periodic Air Duct Cleaning Helps You Breathe Easy

Even with regular filter changes and annual maintenance, your ductwork will become dirty. Over time, this could affect air quality, or even allow mold to begin growing in these hard-to-reach spaces. Every few years, inquire with your service provider about the need for duct cleaning. An inspection can reveal whether there are any issues to address, and thorough cleaning will ensure continued clean air in your home.

Clean the Air Ducts Periodically

This isn’t something that you’ll have to do nearly as often as the other items on this list, but the ducts themselves do gather dust and need to be cleaned every so often. Dust that builds up inside the ducts can affect the air quality in your home, but it can also block airflow. Ducts are already frequently responsible for some loss of efficiency and a buildup of dust will only make that worse. As we previously mentioned, cutting down on airflow through the system will result in higher power bills and more frequent repairs for the unit.

Worse still, mold can also end up growing inside ducts that haven’t been cleaned often enough. Mold can represent a health hazard for you and your family if the spores are released into the air supply, so it’s important to keep it from growing in the ductwork. The symptoms of mold exposure are fairly similar to allergy symptoms, so it can be hard to tell when spores have gotten into the air. If you or your family start to experience unexpected allergy-like symptoms, especially outside of allergy season, there could be mold growing somewhere in your home, including in the ducts.

It’s not generally recommended to clean your own ducts, even if you’re an experienced handyman. Every inch of the ductwork needs to be cleaned and disinfected, especially if you think there might be mold up there. Even a single patch of mold can release spores and start the whole process over again, so it’s important to be thorough. The ducts themselves are also fairly delicate, so it’s difficult to clean them without accidentally causing dents or small holes. We highly recommend leaving this particular process to the professionals.

How often you clean your ducts will depend on a few factors including the climate where you live. As a general rule, it should be done every three to five years, although homeowners living in particularly dusty areas may want to get the ducts cleaned every two years or so. Most HVAC contractors and repair companies will offer this service, which can take a day or two. Ducts may not be the first thing you think about when you put together a maintenance checklist for your HVAC system, but letting dust build up in there can cause you serious problems later on.

Seek Professional Help for Checking Off Your HVAC Maintenance Checklist

Whether you’ve noticed something unusual during your routine HVAC system inspections or it’s time to call in for an annual inspection, a friendly AC service provider can make all the difference. From putting you at ease about the maintenance of your system to answering any questions you have clearly and concisely, having the right contractor on your side is an invaluable asset. Know where to look for help, what questions to ask, and when to call for an appointment. With this HVAC maintenance checklist in hand, you can continue to stay comfortable.

Why HVAC Maintenance is Important

The most immediate impact of focusing on HVAC maintenance will be on the long-term health of each unit. Keeping every part of the system clean and staying up to date with your regular service appointments can significantly increase the lifespan of your air conditioner or furnace. If properly taken care of, an air conditioner can last for 15 to 20 years before it needs to be replaced, and a gas furnace can last up to 30 if properly maintained. Replacing an HVAC appliance can be a pretty expensive proposition, so it’s best to put that cost off for as long as possible.

In the shorter term, a well-maintained AC unit or furnace will also break down far less frequently, saving you money in repair bills and replacement parts. It’s pretty rare for an HVAC part to just suddenly break – typically they start to wear down gradually before finally breaking. Regular maintenance appointments will allow your HVAC technician to catch the signs of wear and tear before it becomes a serious problem, saving you from suddenly having to pick up a replacement compressor or coil. If you take good care of your air conditioner and get lucky, all the major components can last for the full lifespan of the unit itself without requiring a replacement.

Finally, maintenance has a direct impact on the efficiency of your HVAC system. Air conditioners and furnaces are often some of the biggest electricity drains in the average household, so it’s important to make sure they’re running as efficiently as possible. In fact, some regular maintenance to keep your air conditioner running smoothly can save you up to 30% on your utility bills. When the system doesn’t have to work as hard, it doesn’t use nearly as much electricity and the strain on your wallet is lessened.

If you’re in Marin, Sonoma, or Napa Counties and you’re interested in learning more about HVAC maintenance or you want to set up a service appointment, Valley Comfort Heating & Air is happy to help. You can stop by our physical location in Santa Rosa, get in touch with us through our website here, or just give us a call today at (707) 329-4120.