What to check on your HVAC before summer arrives (and what to leave alone)

A lot of air conditioners were tested last weekend. Some didn't make it.

If yours did, that's good news, but another stretch of heat is coming in the next few days, and the same problems that showed up last week will show up again.

Most of them aren't inevitable. A few are easy to prevent yourself. A few others look easy to prevent and aren't, and the difference matters more than most homeowners realize.

Two GTA contractors, Bulut Bozkurt of Bulletproof Heating & Cooling and Fasi of AFG Heating and Cooling Services, shared their experiences about where that line actually sits.

What you can do yourself

Change the filter. Most need replacing every one to three months, but that's a starting point, not a rule. Hold it up to a light, if light barely passes through, replace it regardless of when you last swapped it. A clogged filter is the single most common cause of HVAC problems and costs about fifteen dollars to fix.

Keep the outdoor unit clear. Two feet of breathing room on all sides. No leaves packed against the fins, no shrubs growing into it. If you do want to rinse the outside with a garden hose, ensure the weather is consistently above freezing, turn the power off first, and be careful. Bulut has been called out to homes where a well-meaning homeowner sprayed down their unit without killing the power and caused an electrical short in the process.

Leave your vents open. Closing registers to redirect airflow or "save energy" in unused rooms doesn't save energy, it forces the blower to push air against more resistance. Close enough vents and you're running the motor at higher amperage than it was designed for. That's how you burn out the motor. Leave them open.

Test the system before you need it. If you haven't run your A/C yet, take the time today to drop it a few degrees below room temperature, and wait. If cool air comes out within a few minutes, you're in good shape. If it doesn't, you want to know now, not during the first heat wave, when every HVAC contractor in the city is booked out two weeks.

What to leave alone

Beyond filters, most HVAC maintenance should be done by Pros. The systems involve refrigerant, gas, and electrical components, and a well intentioned DIY can end up being dangerous or end up being more expensive than years of servicing. 

Fasi has seen both ends of this.

One customer installed their own water heater, hired a gas fitter to connect the gas line, but handled the plumbing themselves. The flexible hose they installed wasn't up to code, eventually ruptured, and flooded the basement. 

Another customer did their own venting, and it was so far outside code that they were at genuine risk of carbon monoxide poisoning. Neither of these homeowners thought they were cutting corners. They just didn't know what they didn't know.

The same principle applies to maintenance, not just repairs. Fasi had a customer who skipped professional servicing for three or four years because nothing seemed wrong. By the time they called, the compressor had failed, partly from accumulated neglect the homeowner couldn't see, and partly from the kind of buildup that only shows up when you take the unit apart and clean it properly. The repair cost around $1,200 (much more than four years of annual maintenance). And because the failure was attributed to neglect, the warranty was void. 

Fasi noted that suppliers can usually tell when a breakdown is a normal wear failure vs. neglect, they've seen enough of them.

Signs to call a pro immediately

Both contractors flagged the same categories: sound, smell, and behaviour.

Sound. An AC humming louder than usual, a unit turning off with a clunking noise, or a blower motor making any kind of grinding or screeching sound are all early signs of something breaking down. Don't wait to see if it goes away.

Smell. A burned-wire smell from the furnace or air handler means something is overheating. Gas smell means stop what you're doing, leave the house, and call.

Behaviour. If the system turns on, runs briefly, shuts off, and repeats, that's short-cycling, and it won't resolve on its own. If it's running but not actually cooling or heating to temperature, and the filter is clean and the thermostat is set correctly, something mechanical is wrong.

In all three cases: don't troubleshoot. Call a pro.

On annual service

Bulut recommends a twice-yearly visit (spring and fall) for most homes. Part of what a Pro does on those visits is what Fasi's compressor story illustrates: they're checking things you can't easily see yourself, and catching the slow-developing problems before they become warranty-voiding, four-figure repairs.

Whether a full service plan makes sense depends on your system and your situation. For heat pumps, older gas furnaces, or systems still under a warranty that requires documented maintenance, a regular professional visit earns its keep. 

Either way, the time to find out your air conditioner has a problem is not the afternoon the temperature hits 35.

Looking to hire a Pro to help with your HVAC needs? Request a quote from AFG Heating and Cooling Services or Bulletproof Heating & Cooling, or find more Pros referred by your neighbours right on Quartermaster.