27 May. 19

When to clean your HVAC air ducts?

Over the years, HVAC (Heating, Ventilation, Air Conditioning, and Cooling) systems have become more popular than ever in homes and offices. Today, they are a feature of almost every dwelling and for a good reason. As sweltering summers and frigid winters of record-breaking degrees are slowly becoming the norm, proper heating and cooling are a must have for the comfort and safety of the occupants of any building.


They quite literally, ensure we neither turn to popsicles nor melt into sludge by controlling the indoor climate and airflow. In addition to this as well, HVAC systems also prevent the growth and spread of mould, which may cause respiratory or other health-related issues.

Now having an HVAC system installed in your home is one thing; having it function at optimum capacity is an entirely different kettle of fish. Why? Well just like any sports car or heavy duty machine, all heating or cooling systems need to be in pristine working condition to get the best value out of them. This is where HVAC maintenance comes in.

As with all things, people fail to grasp the entire scope of HVAC maintenance. In this case, most people erroneously assume it begins and ends with the furnace or boiler. In reality, however, clean air ducts are just as essential to having a functional system. This is because, without regular maintenance, dust particles and mould spores from clogged air ducts eventually cause irritation like sneezing and watery eyes in people. Worse still, for those who have conditions like asthma, bronchitis or related respiratory diseases, airborne particles like dust, pollen, pet fur, and insect droppings are doubly detrimental.

Apart from these health issues, though, there are other reasons why clean air ducts are non-negotiable when it comes to your HVAC system. They are:

Improved air quality

Proper HVAC maintenance in addition to keeping your home warm or cool, would also prevent problems with air quality. This is because clean air ducts generally lead to cleaner air in circulation. On the other hand, a dirty duct usually serves as a breeding ground for dirt, mould, and bacteria, which can all lead to or aggravate severe respiratory problems.

Reduction in utility bills

One of the significant advantages of having a properly functioning HVAC system is that it reduces costs as less money is spent on electricity, heating and cooling costs. Proper maintenance also prevents the need for significant repairs and replacements which hardly ever come cheap.

The lifespan of the system

As with all things, proper HVAC maintenance ensures the system functions for more extended periods and at full capacity as well. It is generally agreed that a properly maintained HVAC unit can last for as long as ten years. And considering the costs of installation in the first place, it is generally advisable to make sure maximum benefits are reaped from it.


Closely related to the lifespan of the system is its smooth and efficient running.  Experts agree that poorly maintained units need to work 20% harder to achieve the same amount of output as would a well-maintained machine. Basic laws of physics show that less energy expended in the operation of a machine means less stress on its components. Less stress on components, in turn, leads to less wear and tear on the system, which ensures it runs in top condition for more extended periods.

Fewer emergency repairs

Regular HVAC maintenance ensures systems are less likely to fail during the months of hard use (summer and winter months).


When a problem occurs, the faulty component may be covered by a warranty. This generally is another reason for regular HVAC maintenance as defective components covered by warranties can be fixed before it is too late. This saves both time and money.

Related article: The Ultimate Furnace Maintenance Guide: Tips & How To

Cleaning your air ducts: What you need to know?

HVAC maintenance doesn’t stop with the knowledge that clean air ducts are a necessity. You do NEED to clean them out, and this is where many drop the ball. The most common reason for this is that they do not know how frequently to clean them.

In light of this, we have decided to provide a few ways for you to know when to clean out your air ducts.

When to clean out your air ducts

Now in most cases, HVAC air ducts only need to be cleaned every three to five years. Certain circumstances may, however, warrant you clean them earlier than that; especially if you live in dusty or allergen-prone areas or also when work has been done to your home. Some of the signs to help you know when to clean your air ducts are:

1.Visible mould growth

Unsightly mould growth is by far one of the surest ways to know the time has come for you to clean out your air ducts. If you or your HVAC provider find mould growing in the ducts, the first step should be to test the contaminated area to confirm if it is genuinely moulded and nor mere dirt. If indeed it turns out to be mould, then the ducts should be cleaned and sanitized, and the entire HVAC system inspected immediately. This is because mould exposure has been linked to severe health problems like respiratory issues, eye irritation, throat irritation, and skin irritation.

It is essential to point out though that the average HVAC technician may not possess the necessary skills to properly identify mould. We, therefore, advise you to seek the services of a certified indoor quality expert (the Indoor Quality Association is an excellent place to start) when dealing with mould-related issues.

2. Excessive debris

Debris on air vents and filters is generally a bad sign for your air ducts. Granted, a minor accumulation of debris is expected as it is impossible to keep living or working spaces in pristine condition 24/7. However, when your air ducts have accumulated enough dust and debris to cause blockages or airflow restrictions, your air ducts are due for a clean.

It is particularly important to pay attention to this because debris in ducts means more work for your HVAC system. This, in turn, inevitably leads to an increase in your utility bill and premature component wear.

3. Pest infestation

If you have noticed a sudden outbreak of pests like rodents or insects, it is vital to have your air ducts cleaned as soon as possible. This is because husks from insects as well as rodent dander and droppings can lead to blockage of air ducts.

Besides, viruses and bacteria vectors like rats carry can cause severe health conditions if left unattended.

Related article: How to keep pests away from my HVAC system?

4. Increased allergy symptoms

If you notice your allergies worsen, or you suddenly develop allergies you’ve never had,  you may need to check your air ducts. Why? Dirty air ducts nearly always lead to increased and worsened symptoms for people who have asthma or some other allergy. This is because the dust and other harmful particles which cause such allergies are circulated throughout the home.

Where the air filter is damaged or clogged, the chances of such allergies being caused by dirty air ducts become all but guaranteed.

5. Pets

As with pests, fur from pets such as cats and dogs can constitute a great nuisance to air ducts. Their long period of occupation in homes means they contribute to more significant degrees to the accumulation of debris in ducts that pests.

This, however, in no way means you should get rid of your adorable four-legged friends. Just remember to clean your air ducts more frequently than usual if you have any.

6. Excessive household dust.

Granted, it’s impossible to keep your homes or offices 100% dust free all year round. However, while an occasional little dust is one thing, having your place look like an abandoned museum is a whole different level altogether.

Excessive amounts of dust are therefore another telltale sign that it is time to clean out your air ducts. It is important to note that sometimes, visible dust may be due to very dusty air registers. However, when dust levels remain the same even after frequent changes of the air filter, you can be sure it’s time for an HVAC maintenance call.

7. When you remodel

Remodelling is never a friend to clean air ducts. This is because more often than not, debris from the remodelling process (even though you can’t see it), always finds a way to settle in your air ducts. Thus, whenever your homes or offices have been remodelled, your next course of action should be a call to an HVAC technician to clean your ducts.


8. When you move to a new home

Construction and large quantities of dust go hand in hand.  On account of this, we advise you to engage the services of an HVAC technician whenever you get a new home. This advice also applies to a rented apartment at as well. Whenever you move to a new apartment and are unsure when the air ducts were last cleaned, it is also advisable you schedule an appointment with a professional to ensure clean air ducts for your system.

9. Unexplained spikes in energy bills 

As a norm, your heating and cooling costs should be a relatively predictable year in, year out. If you ever notice your energy bills climbing with no reasonable explanation like increased usage or long-running mechanical problems, your ducts are likely to require cleaning. This is because while clean air ducts function at optimum capacity, clogs or leaks in the duct significantly reduce its efficiency. The good thing, however, is that a simple HVAC maintenance call can quickly fix this.

10. Uneven air flow

With clean air ducts, air generally flows with good strength from all registers in all rooms. When the ducts are clogged; however, the air only flows with good strength from some registers and others with inferior strength. This is because the dust and debris which may have formed blockages in the duct restrict the air pressure flowing out of some registers in other rooms. Uneven airflow from your HVAC system is, therefore, another excellent indicator of when you should clean out your air ducts.

It is essential, though, to note that this could also be caused by leaky ducts that may have degraded over time. It is therefore advisable to ask an HVAC technician to check for both during inspections.

11. Unpleasant Odors

While many factors can cause this, sudden unpleasant odours in your home or office can also indicate it is time to clean your ducts. This is because unlike clean air ducts, dirty, clogged air ducts may begin to smell bad if blocked with mould or dead pests.

Can you clean your air ducts yourself?

Today there are a significant number of activities you can do without needing the services of a professional. Cleaning your air ducts, however, is not on the list of such events.

The first reason for this lies in the difference between the tools of a professional and the average homeowner. Professional air duct cleaners make use of commercial-grade vacuum systems and powered brushes to remove dirt and debris in your HVAC system without worsening the quality of indoor air. On the other hand, residential vacuum cleaners and attachments are simply not powerful enough to clean the air ducts properly. DIYers are more likely to do more damage to the air ducts.

Furthermore, professionals are trained to do more than clean air ducts. They also spot other problems affecting HVAC systems which the average DIYer is simply not aware of. We therefore strongly advise you always contact a professional whenever your air ducts require cleaning.

It is essential that you know air duct cleaning is subject to scams like any other business known to man. Such scams usually come in the guise of ridiculously low prices or “special services” that you can only enjoy after paying “extra charges.”


Everyone desires (and deserves) clean air ducts in their homes and offices. Unfortunately, however, few ever experience such a “luxury” as they remain puzzled by the question of the exact time to clean their ducts. But as with all seemingly complex problems, the solution to this is patently simple. Simply observe the precautions listed above and join the “elite” group of Canadians living in the lap of luxury. Our HVAC experts can help you make sure that your ducts are always clean. Contact us today!