What’s Actually Done During an HVAC Maintenance Visit? A Technician’s Checklist

“Maintenance” covers everything from a 15-minute filter swap with an invoice to a genuine top-to-bottom service call, and from the driveway they look identical. Here’s exactly what happens during a real maintenance visit — the checklist our technicians actually run — so you know what you’re paying for.

The fall furnace visit

• Heat exchanger inspection — checked with a camera for cracks that can leak carbon monoxide into your air. This is the single most important item on the list, and the one drive-by tune-ups skip.
• Flame sensor and igniter — cleaned and tested. These two parts cause most winter no-heat calls, and both announce their failure in advance to anyone who measures them.
• Gas pressure and combustion — measured against manufacturer spec, not eyeballed. Wrong gas pressure quietly destroys heat exchangers.
• Safety controls — limit switches, pressure switches, and rollout switches tested; venting checked for slope, corrosion, and blockage.
• Blower and filter — blower wheel cleaned, motor amps measured, filter replaced, airflow verified. Low airflow is the silent killer of furnaces and the most common thing we correct.
• Full cycle test — thermostat to burners to blower to shutdown, end to end, temperatures measured across the system.

The spring AC visit

• Coil cleaning — outdoor condenser coil washed; indoor coil inspected. A dirty coil makes the system work harder for less cooling and shows up on every summer electric bill.
• Refrigerant charge — measured, not guessed. Low charge means a leak; we find it rather than just topping off year after year.
• Electrical — capacitor strength, contactor condition, wire connections, motor amps. The capacitor is the classic July failure, and it’s measurable in May.
• Condensate drain — cleared and treated. Clogged drains cause ceiling stains and shutdowns in the middle of cooling season.

What each visit prevents

The pattern across both seasons: nearly every emergency call started as a measurable, cheap-to-fix condition months earlier. The weak capacitor, the dirty flame sensor, the slow refrigerant leak — caught during maintenance they’re minor line items; caught at 11 PM in January they’re an emergency call. We put what a tune-up costs in context in furnace tune-up cost in Chicago and when to schedule furnace maintenance.

Maintenance plans vs. one-off visits

A maintenance agreement bundles the fall furnace visit and spring AC visit, adds priority scheduling when the weather turns, and discounts repairs if something does fail. If you own your home and plan to stay, it beats buying tune-ups one at a time — and you’ll never forget to schedule one, because we call you.

Want your system on the list before the season turns? Call Around the Town Heating & Cooling at (312) 243-9896 or see our HVAC maintenance plans — licensed, NATE-certified, serving Chicago since 2004.