In Calgary, our air can be filled with dust, construction debris, and seasonal allergens.

• • The Problem: When your air filter is caked in dust, air can’t flow through the system. This causes the indoor evaporator coil to drop to freezing temperatures, eventually turning into a block of ice that blocks all cooling.

  • The Fix: Check your furnace filter. If you can’t see light through it, replace it. Pro Tip: During heavy smoke or high-pollen seasons in Alberta, you may need to change your filter every 30 days.

Our local power grid can occasionally flicker during summer storms, or your unit might simply be aging.

• • The Problem: If you hear your indoor fan blowing but don’t hear the low hum of the outdoor compressor, a capacitor might have failed. Think of the capacitor like a battery that gives the motor the “kick” it needs to start.

  • The Fix: This requires a professional. Capacitors store a high electrical charge and can be dangerous to handle without the right tools and training.

Your outdoor unit (the condenser) acts like a heat exhaust. It needs plenty of “elbow room” to dump the heat it pulled from your house.

• • The Problem: Overgrown shrubs, tall grass, or even piles of “poplar fluff” can wrap around the unit like a blanket. If the heat can’t escape, your AC won’t cool effectively.

  • The Fix: Clear a two-foot perimeter around your outdoor unit. Use a garden hose (on a gentle setting) to rinse away dirt and debris from the metal fins.

Sometimes the issue isn’t the AC at all—it’s the brain of the operation.

• • The Problem: If your thermostat has dead batteries or is placed in a spot that gets direct afternoon sun, it will give your AC the wrong instructions.

  • The Fix: Replace the batteries. Ensure the setting is on “Cool” and the fan is on “Auto.” If your thermostat is near a window or a heat source, it may need to be relocated by a pro.

Your AC uses a special fluid called refrigerant to move heat. It’s a closed system, meaning it should never “run out.”

• • The Problem: If there is a tiny pinhole leak in the copper lines, your system will lose its ability to absorb heat. You might notice a hissing sound or see ice on the lines near the outdoor unit.

  • The Fix: Never try to “top up” refrigerant yourself. It requires a licensed technician to find the leak, seal it, and recharge the system to environmental standards.