The Halton Hills Homeowner's Seasonal HVAC Checklist

HVAC equipment lasts longer and runs cheaper when it's maintained. But maintenance isn't just calling a contractor twice a year — there are practical things every Halton Hills homeowner should do throughout the year, and an equal number of "tips" floating around that are worthless or actively harmful. Here's the actual list, season by season.

Spring — March, April, May

Heating season is winding down; cooling season is coming. This is the most important maintenance window of the year.

• Book your AC tune-up. April is ideal — contractors are still in pre-season scheduling mode, before the May rush. A proper tune-up runs $130–$200 and includes refrigerant level check, capacitor health, contactor inspection, condenser coil cleaning, and condensate drain clearing.
• Replace your furnace filter. If you've been heating heavily through winter, the filter is overdue.
• Clear debris from around the outdoor AC unit. Leaves, twigs, plastic bags from winter winds — anything that accumulated should be removed. Leave 2 feet of clear space on all sides.
• Test your AC before you need it. Run the AC for 15–20 minutes on a warm day to confirm it's cooling properly, listen for unusual noises, and check that condensate is draining (not pooling at the indoor coil).
• Check your outdoor unit's level. Pads can shift over winter. An out-of-level AC accelerates compressor wear.
• If you have a humidifier: clean the pad, turn off the water supply for the warm-weather months, and disable humidifier mode on your thermostat.

Summer — June, July, August

AC running heavily. Watch for warning signs that signal repairs are needed before they become emergencies.

• Continue monthly filter changes. Higher airflow during AC season means filters load faster.
• Keep outdoor unit clear of vegetation growth. Lawn cuttings, climbing vines, and overgrown shrubs all reduce condenser efficiency. Trim back to 2 feet clear.
• Watch for warning signs:
  • AC running but house not cooling → could be refrigerant low or compressor failing
  • Iced-up coil or refrigerant lines → turn off immediately, call for service (running an iced AC damages the compressor)
  • Water pooling near indoor unit → clogged condensate drain, fixable in 20 minutes if caught early
  • Strange smells when AC starts → could indicate mold growth in ductwork or a stuck blower wheel
  • Higher than usual electric bills with no obvious cause → AC efficiency dropping, often from low refrigerant
• If you have a smart thermostat: review the cooling schedule and adjust setbacks. Setting back 4–6°F when away saves real money.
• Use ceiling fans to extend AC range. A ceiling fan running counter-clockwise in summer makes a room feel 4°F cooler at the same thermostat setting.

Fall — September, October, November

The most important season for heating equipment maintenance. Don't skip it.

• Book your furnace tune-up before mid-October. Wait until November and you're competing with thousands of other Halton Hills homeowners for limited slots, and pricing increases.
• What a real furnace tune-up includes:
  • Combustion analysis (CO/CO2 levels)
  • Heat exchanger visual inspection (cracks = safety hazard)
  • Flame sensor cleaning
  • Igniter resistance check
  • Blower motor amp draw test
  • Belt and pulley inspection (older units)
  • Gas pressure verification
  • Venting and combustion air check
  • Filter replacement
  • Thermostat calibration check
• Test the heat before you need it. Run the furnace for a full cycle in early fall. Listen for unusual noises (banging on startup, squealing blower bearings, repeated clicking) and address them before the first cold snap.
• Replace the filter and check filter sizing. If you've been switching brands or sizes, confirm what your system actually needs (in the manual or on the inside of the access panel).
• Set up your humidifier: clean and replace the evaporator pad, turn the water supply back on, set humidifier mode on your thermostat for 35–40% target humidity.
• Check that all supply registers are open — at least partially. Modern furnaces are sized assuming all registers are providing airflow.
• Test your CO detectors. Replace batteries; replace detectors themselves if older than 7–10 years. Heating season is when they earn their keep.

Winter — December, January, February

Furnace running constantly. Watch for problems and don't let small issues become no-heat emergencies.

• Monthly filter changes during heavy heating use. A clogged filter is the most common cause of furnace problems in winter.
• Keep outdoor air intakes clear — particularly important for high-efficiency furnaces and heat pumps that vent through the side wall. Snow drifts can block these. A blocked intake causes the furnace to short-cycle or shut down on safety lockout.
• For heat pumps specifically: don't let snow accumulate on the outdoor unit. Brush off snow buildup gently with a broom (don't use sharp tools that could damage the fins). The unit needs airflow to work as a heater.
• Set a baseline temperature when away — never below 13°C in winter for occupied homes. Pipes freeze faster than most homeowners expect, and "saving money" by setting back to 8°C while at work has caused more burst pipes than I can count.
• Watch for warning signs:
  • Furnace running constantly without keeping up → undersized, dirty filter, or developing problem
  • Short-cycling (5-minute on/off bursts) → flame sensor, oversized furnace, or restricted airflow
  • Unusual smells (especially after a long off period) → first start of season is normal for 10 min, persistent smells warrant a service call
  • CO detector chirping → don't ignore. Get it checked.
• Save the after-hours emergency contact: program your contractor's emergency line into your phone. When the furnace fails on a Sunday night at -20°C, you don't want to be searching online.

Frequently asked questions

Most of the seasonal items above are covered in our annual preventive maintenance plans — two visits a year (spring AC, fall furnace), priority emergency service, and discounts on parts. Or just book a one-time tune-up here when the season's right.