Poorly Maintained Air Conditioning: How Simple Negligence Can Double Your Energy Bill

Vanishing savings: the direct impact of poor maintenance on your air conditioning system

When we talk about energy efficiency, thermal comfort, and the longevity of HVAC systems, one element consistently comes up as essential: regular maintenance. At AirGreen, we’ve seen time and again across Montreal, Laval, Longueuil, the North Shore, and the South Shore that even small oversights — like a clogged filter or a blocked outdoor unit — can lead to a dramatic spike in energy consumption. In this article, we’ll show how poorly maintained air conditioning can literally double your electricity bill, sharing real-life cases, technical insights, and the practical solutions we implement every day.

A clogged heat pump or wall-mounted AC: a silent energy trap

When dust, pet hair, or pollen builds up on the filters or evaporator coils of an air conditioning system, it’s forced to work harder to reach the set temperature. The result: the compressor runs longer, pressure builds up, and the components wear out prematurely.

During a recent service call in Brossard, our AirGreen team was called in for a Gree Extrême 18,000 BTU wall-mounted unit that was performing poorly. After an inspection, we discovered the filters had never been cleaned since installation — over three years ago. The customer had seen their Hydro-Québec bill increase by 47% in a single year and didn’t understand why. A full maintenance service, including high-pressure cleaning, refrigerant check, and system reset, helped reduce consumption by 38% the following month.

The real-world consequences of poor HVAC maintenance

Here are the main effects of neglected maintenance that we regularly see during service calls in Montreal and surrounding areas:

• Excessive energy consumption (up to +100%)

• Loss of seasonal efficiency (SEER and HSPF ratings)

• Reduced airflow and lower comfort levels

• Risk of freezing on the indoor coil

• Mold growth in ducts or on the evaporator

• Shortened lifespan of the compressor and fans

In short, neglecting maintenance results not only in lost money, but also in the accelerated breakdown of your equipment.

Preventive maintenance: our solution at AirGreen

At AirGreen, we’ve developed a structured preventive HVAC maintenance service across the Greater Montreal Area, which includes:

• Thorough cleaning of filters, coils, and fans

• Refrigerant level check (R-32, R-410A, R-454B, etc.)

• Performance analysis and recalibration

• Inspection and securing of electrical connections

• Leak detection and noise diagnosis

For example, in Laval, we serviced a rental building equipped with Fujitsu KZAH R-32 wall-mounted AC units. After just 12 months of heavy use with no maintenance, tenants were complaining of weak cooling. Through proactive maintenance, including outdoor coil cleaning and filter replacement, we restored full operation and reduced service calls by 85%.

How often should your air conditioner be serviced?

We recommend a full maintenance once per year, ideally in the spring, before the summer heat hits. This helps:

• Prevent breakdowns during peak season

• Optimize energy performance

• Extend your system’s lifespan

In certain cases — like commercial properties, condos, or homes with pets — biannual maintenance may be necessary.

What our customers often don’t know

Many homeowners assume that if the system “still works,” everything is fine. But even without strange noises or a full breakdown, a poorly maintained heat pump can operate at just 50% of its optimal capacity — and cost you double in electricity.

A striking example: in Saint-Hubert, we serviced a home with a Sharp ZU1 24,000 BTU wall-mounted air conditioner. After a summer of nonstop use, the unit seemed “okay” but was generating an unusually high electric bill. After cleaning and recalibrating, we proved via real-time monitoring that the system had regained full efficiency within 2 hours.

Grants and incentives: maintenance matters

Did you know that some programs like Hydro-Québec’s LogisVert require that eligible systems be properly maintained to keep their long-term eligibility? Poor maintenance can lead to:

• Denial of grant or rebate

• Voided manufacturer warranty

• Health risks for occupants (mold, allergens)

We guide our clients across Montreal, Longueuil, the South Shore, and the North Shore in meeting the maintenance requirements for government programs.

Our practical advice to avoid costly mistakes

1. Clean your filters every month, especially during summer.

2. Keep the outdoor unit clear (free of leaves, snow, or debris).

3. Avoid setting your indoor temperature too low, which overburdens the system.

4. Subscribe to an AirGreen maintenance contract — our teams will automatically remind you when service is due.

AirGreen: expertise, transparency, proximity

Thanks to our hands-on experience across the Greater Montreal region, we’ve developed a personalized HVAC maintenance approach. Whether you're in Terrebonne, Boucherville, or Pointe-Claire, our mobile teams respond quickly with professional tools and full transparency about the work done.

We believe that HVAC maintenance is a smart investment, not a useless expense. Our customers who opt for annual service save on average 20 to 40% on their energy bills in the first year alone.