Air Conditioning Repair in Mr. Furnace
There’s nothing worse than discovering your air conditioner quit on you during a heatwave. Whether it’s blowing warm air, making strange sounds, or just won’t start, Mr. Furnace Heating and Air Conditioning is the team locals trust when cooling systems go rogue. Based in St. Catharines for over 45 years, we’re the folks who show up when you need real answers, not a call centre and a waiting list. No drama. Just solid, dependable AC repair when it matters most. Just solid, dependable AC repair when it matters most.

Why Choose Mr. Furnace for Your Air Conditioning Repair?
We’re On Our Way!
You don’t need a technician next week, you need one today. That’s why we’re already nearby. Our repair team is based in St. Catharines and ready to roll seven days a week, holidays included. We don’t farm out work. We don’t make you wait. We just fix the issue and leave your place cooler than we found it.
Repairs That Last, Not Just Quick Fixes
We’ve seen it all, from systems that hum but don’t cool, to units that died mid-summer. Our team doesn’t do quick patches that come undone next week. We track the problem down to its core, explain it in plain English, and repair it so it stays fixed. Because band-aids belong in first aid kits, not your HVAC.
Reliable Local Experts with Decades of Experience
Since 1978, homeowners across St. Catharines have trusted Mr. Furnace for reliable air conditioning repair. Our certified technicians are experts in diagnosing and repairing all makes and models. We understand the specific cooling demands of Niagara homes and bring decades of experience to every repair we complete.
Customer-First Service with a Satisfaction Guarantee
You’ll always know what’s going on with us. We explain your options clearly, keep you looped in throughout the repair, and back our work with a 90 day satisfaction guarantee that actually means something. If something’s not right, we’ll come back and address it. No back-and-forth, no runaround.
Is your AC not cooling, making strange noises, or driving up energy bills? Mr. Furnace provides expert air conditioning service with fast, reliable air conditioner repair, even after-hours or on weekends. Get your AC running smoothly—schedule your repair today!
Our Air Conditioning Repair Process
Step 1: Full System Inspection
We begin every job with a complete inspection of your air conditioner, from coils and compressors to wires and refrigerants. This allows us to identify the issue accurately and catch any developing problems before they become major repairs.
Step 2: Advanced Diagnostic Testing
Using advanced testing equipment, we check for refrigerant leaks, thermostat errors, faulty motors, and electrical faults. This process ensures your air conditioning repair addresses the root cause, not just the symptoms.
Step 3: Upfront Repair Recommendations
Once we identify the issue, we explain everything in plain language and provide straightforward, upfront pricing. That way, you always know what to expect before we begin repairs.
Step 4: Reliable Parts Replacement
If your air conditioner needs a part replaced, we’re ready. Our service vehicles are stocked with the most commonly needed parts, including capacitors, relays, fuses, fan motors, and contactors. This allows us to handle most repairs in a single visit, restoring your cooling system faster and minimizing disruption to your day.
Step 5: System Cleaning & Efficiency Boost
A clean system runs more efficiently. As part of our air conditioning service, we clean coils, filters, and drains to improve airflow and prevent recurring issues. This also helps reduce energy use and boosts cooling power.
Step 6: Final Testing & Optimization
Before we leave, we double-check system performance, airflow, and temperature settings. We make any final tweaks needed so your air conditioner keeps your home consistently cool long after we go.
Common Air Conditioning Problems
Even high-quality systems can fail over time. Here are a few common AC issues we fix with professional air conditioning repair:
AC Running but Not Cooling
- Refrigerant Leak: If your system has lost refrigerant, it can’t absorb heat properly—resulting in warm air.
- Thermostat Malfunction: A faulty thermostat may fail to send the signal to cool or maintain the set temperature.
- Blocked Condenser Coils: Buildup on your outdoor condenser coils limits heat transfer, reducing overall cooling efficiency.
AC Won’t Turn On
- Faulty Capacitor: A weak or dead capacitor can stop your system from starting, often accompanied by clicking sounds.
- Electrical Failure: Damaged wires, corroded connections, or faulty relays can interrupt power to your unit.
- Tripped Breaker or Blown Fuse: Electrical overload or short circuits can shut down your system completely until reset or repaired.
Strange Noises or Leaks
- Buzzing or Rattling Sounds: These often indicate a loose part, worn motor, or electrical component failure.
- Hissing Sound: High-pressure gas escaping from a leak in the refrigerant line or expansion valve can cause a hissing sound.
- Water Pooling Around the Unit: A clogged drain or broken condensate pump can lead to water pooling near your system, sometimes resulting in water damage or shutdown.
If you’re dealing with any of these issues, Mr. Furnace’s certified team is ready to help. We’ll diagnose the problem quickly, explain the best repair options, and get your air conditioner running efficiently again.
Frequently Asked Questions About Air Conditioning Repair
Experiencing AC issues? Get fast, expert air conditioning repair from Mr. Furnace Heating and Air Conditioning with 24/7 emergency service, no hidden fees, and lasting solutions. Our certified technicians provide expert air conditioning service to restore your home’s comfort quickly. Book your repair today and stay cool.
How Often Should I Have My Air Conditioner Serviced?
We recommend annual service, ideally in the spring before peak cooling season. Regular air conditioning service includes coil cleaning, electrical testing, and refrigerant level checks. These maintenance tasks help avoid surprise breakdowns and keep your system efficient, extending its life and reducing the need for major repairs.
How Much Does It Cost to Fix an Air Conditioner That Is Not Cooling?
The cost of air conditioning repair depends on the root issue. Simple problems like clogged coils or a malfunctioning thermostat may cost less to fix. More serious issues, like a refrigerant leak or faulty compressor, can be more complex. We’ll provide a full diagnosis and quote before doing any work, so you can make an informed decision.
How Many Years Does an Air Conditioner Last?
Most central air conditioning systems last between 10 to 15 years. With routine maintenance and timely repairs, your system could continue working for 20 years or longer. Factors like usage, climate, and service quality all play a role in the lifespan of your air conditioner.
When Should I Replace My AC?
If your unit is 15 years or older and frequently needs repairs, it may be more cost-effective to replace it. Systems that no longer cool efficiently, cost more to run, or need repairs that total half the value of a new installation are often better replaced. Mr. Furnace can assess your current unit and offer straightforward recommendations based on performance, cost, and energy savings.