Is Duct Cleaning Worth It? An HVAC Technician's Perspective
Is duct cleaning worth it?
This is by far one of the most common questions people ask about duct cleaning who live in the SDG area.
But after almost 20 years working in the HVAC trade, I think there's a bigger question homeowners should be asking first:
Is maintaining the entire HVAC system worth it?
Once you start looking at the bigger picture, the discussion about duct cleaning changes.
Your furnace, blower motor, furnace filter, return ductwork and supply ductwork all work together. They aren't completely separate systems.
So why do we often maintain one part while completely ignoring another?
Think About Your Car for a Minute
Would you change the oil in your car but never change the oil filter?
Probably not.
Now, I'll be the first to admit that comparing automotive maintenance to HVAC maintenance isn't perfect. They're completely different mechanical systems.
But there's still a point to the comparison.
Most people understand that maintaining a vehicle means looking after more than one component.
So why do so many homeowners have their furnace maintained every year while never giving any thought to the duct system connected to it?
I've lost count of how many homes I've been in where the homeowner tells me:
“We've never had the ducts cleaned.”
Sometimes they've lived there for 10, 15 or 20 years.
Other homeowners believe duct cleaning is a complete scam. And some simply assume there's no reason to clean the ductwork because:
“We get our furnace tuned up every year.”
That's the misunderstanding I want to address.
What Does a Furnace Maintenance Actually Do?
A furnace maintenance is an HVAC service performed by a qualified HVAC technician to inspect, test, clean accessible areas and, where necessary, adjust the furnace before or during the heating season.
Here in Eastern Ontario, our heating season can be long.
Some homeowners start using their furnaces in September, and depending on the year, we can still be turning the heat on well into spring.
So having your furnace inspected and maintained isn't a bad idea.
However, there's something homeowners should understand:
A furnace maintenance isn't a complete cleaning of your entire furnace and HVAC system.
Yes, the technician will normally clean accessible areas.
When I perform furnace maintenance, I'll vacuum loose dust, debris and cobwebs from the furnace cabinet and compartments where appropriate.
But one of the dirtiest parts of furnaces is something that isn't removed and thoroughly cleaned during routine maintenance:
The blower assembly.
What About the Furnace Blower Motor and Blower Wheel?
This is important because it helps explain why I don't consider properly performed duct cleaning a scam.
The furnace blower moves air through your entire forced-air system.
Air comes through the return ductwork, passes through the filter and furnace, and the blower sends air back through the supply ductwork and into your home.
If your blower wheel is heavily covered in dirt, there's a good chance the return ductwork isn't spotless either. The return system is constantly pulling air back toward the furnace. Along with that air comes dust, pet hair, human hair and other debris that naturally accumulates throughout a home. The furnace filter is designed to catch much of this material, but that doesn't mean everything is caught.
I've pulled blower assemblies out of furnaces and found blower wheels absolutely covered in dirt and debris. When I see that, one of the things I want to know is what the rest of the return-air system looks like.
A standard furnace maintenance doesn't include removing the entire blower assembly and thoroughly cleaning the blower wheel.
Why?
Because doing it properly takes additional time.
Removing a heavily contaminated blower motor does take sufficient time to properly access the wheel.
An HVAC company can certainly do that, but don't be surprised if it's quoted as an additional service.
That's why there's a difference between:
having your furnace maintained
and
having your entire forced-air system cleaned.
Why Does a Furnace Blower Get So Dirty?
There are three things I commonly consider.
1. The furnace filter isn't being changed often enough
If you're changing your furnace filter once a year — or leaving a heavily loaded filter in place for five or six months — you're putting unnecessary strain on your HVAC system.
Pets, number of occupants, filter size, filter type, renovations and how much the HVAC system operates can all make a difference.
Don't rely entirely on a date.
Look at your filter.
2. The furnace hasn't been maintained in years
If nobody has cleaned or maintained the furnace in several years, it's not surprising to find dust and debris accumulating inside.
Even when the blower isn't removed during routine maintenance, vacuuming accessible dust and debris from the blower compartment and furnace cabinet is still better than allowing it to accumulate year after year.
3. The return ductwork has never been cleaned
This is the one I think homeowners often overlook.
Your return ductwork is the direct path bringing household air back toward your furnace filter and blower.
If you can't remember the last time your duct system — particularly the return side — was cleaned, it's time for a duct cleaning.
I'm not saying that seeing a little dust means you immediately need duct cleaning.
I'm talking about systems where years of dust, pet hair and debris have accumulated.
Let me ask you. Does it make sense to clean the furnace, replace the filter and then completely ignore the pathway carrying air back to that equipment?
Can Dirty HVAC Systems Actually Cause Problems?
Yes, and this is something I've personally seen in the field.
This is where my opinion comes from being an HVAC technician rather than simply being a duct-cleaner.
When a homeowner tells me:
“I'm not getting much airflow.”
one of the first things I'm concerned about is air circulation through the HVAC system.
I'm looking at the filter.
I'm looking at the blower.
I'm looking for restrictions.
I'm considering the ductwork.
I'm looking at the evaporator coil where applicable.
And I'm looking at how the system is actually moving air.
I've worked on systems where excessive dirt, restricted airflow and dirty components have contributed to real HVAC problems.
I've seen:
- Blower motors overheat and burn out
- Furnaces trip their high-limit switches because there isn't enough airflow
- Blower wheels heavily coated with dirt and debris
- Dirty evaporator coils restricting airflow
- Dust and debris accumulate inside furnace cabinets and around heat exchangers
- HVAC equipment working harder because proper airflow isn't being maintained
I'm not saying that dirty ducts are the cause every time a blower motor burns out, but it is a problme.
A forced-air furnace depends on airflow.
If dirt and debris are contributing to restrictions or contaminating components involved in moving that air, removing that material is a positive thing for the system.
Will Duct Cleaning Fix an Airflow Problem?
This is where I want to be very clear.
Duct cleaning will not fix every airflow problem.
If your ductwork is improperly sized, duct cleaning won't resize it.
If your blower motor is failing, cleaning the ducts won't repair the motor.
If there's a mechanical or installation problem, it needs to be properly diagnosed.
Just like furnace maintenance, duct cleaning isn't a guarantee that you won't experience HVAC problems in the future. What it can do, however, is address one of the most important concerns in any forced-air HVAC system: providing a clean, unrestricted path for airflow.
Your furnace and air conditioner depend on proper airflow to operate correctly. Keeping the duct system, filter and blower clean helps give that air the clearest path possible through the system.
So What Do I Recommend?
Again, every situation is different.
Some homeowners benefit from having their furnace maintained annually.
Others have extremely clean systems, stay on top of their filters and may choose a different maintenance schedule.
But if you're going two or three years between more thorough HVAC cleaning and maintenance, I think there's a good argument for looking at the whole forced-air system when you do it.
Don't automatically stop at the furnace, get the ducts clean at the same time.
Blower Motor Cleaning During Duct Cleaning
Do we clean the blower motor during duct cleaning?
We will always assess the condition of the blower motor during the duct cleaning. If the blower motor has a normal amount of dust buildup, then yes, we can clean it using high-pressure compressed air and our vacuum system.
However, if the ducts have not been cleaned for a long time and the blower motor and blower wheel are heavily contaminated, a more thorough cleaning may be recommended. This involves removing the blower assembly and separating the motor from the blower wheel so everything can be properly cleaned.
A full blower motor and wheel cleaning can take an additional 45–60 minutes and may cost extra.
If you are interested in having your blower motor cleaned, please let us know before booking. If we can include the cleaning as part of the regular duct cleaning, we will. If a more extensive cleaning is required, we will assess it on an individual basis and discuss it with you first.
Is Duct Cleaning a Scam?
I understand why people ask this.
There have been plenty of questionable practices associated with the duct-cleaning industry: extremely cheap advertisements, aggressive upselling and companies making promises that duct cleaning can somehow solve every problem in your house.
That's not the argument I'm making.
My argument is much simpler.
I've spent almost 20 years working on HVAC equipment.
I've seen dirty blowers.
I've seen motors burn out.
I've seen furnaces going off on high limit because they aren't moving enough air.
I've seen plugged filters and dirty coils.
And i've seen dust and debris accumulated inside furnace cabinets and around equipment.
Those experiences are why I don't believe the answer is:
“Duct cleaning is a scam and never serves a purpose.”
So, Is Duct Cleaning Worth It?
Yes, I believe professional duct cleaning can absolutely be worth it when the condition of the system calls for it.
Think back to the oil-change comparison.
I'm not suggesting ductwork is an oil filter. But the basic maintenance principle still applies:
Why maintain one part of a mechanical system while completely ignoring the condition of everything connected to it?
Your furnace filter matters.
Your blower motor matters.
Your furnace matters.
And yes, the condition of your ductwork matters too.
Based on what I've personally seen working in the trade, keeping a forced-air HVAC system clean and allowing it to move air properly is something I absolutely see value in.
That's how I approach it as an HVAC technician, and that's how we approach duct cleaning at SDG Duct Cleaning.