Seasonal Commercial AC Maintenance: Autumn-to-Winter Care Guide

Published on 2026-09-30 · Suzhou Industrial Park Gulin Commerce Co., Ltd.

As temperatures gradually fall, commercial central and split air conditioners are about to switch from cooling to heating mode. The season change is when commercial AC equipment most often develops faults - after sitting idle, a sudden start exposes dusty filters, blocked pipes and insufficient refrigerant. Based on years of sales and service experience with brands such as Midea, Gree, DAIKIN and Haier, Gulin Commerce has compiled the following seasonal maintenance points.

1. Five Checks to Do Before the Season Changes

• Clean the return-air filter: After a summer of cooling, filters hold large amounts of dust and lint. Remove the filter, rinse with clean water, dry it and refit. A clogged filter can reduce airflow by more than 30%.
• Inspect the outdoor unit heat exchanger: Check whether leaves or debris block the area around the outdoor unit. Dust on the fins reduces heat exchange; clean gently with a soft brush.
• Confirm the drain line is clear: Condensate from summer cooling can leave residue in the pipe. Check the drain is clear before the season change to avoid indoor-unit leaks once heating starts.
• Check electrical connections: Inspect power supply connectors for looseness or aging, especially outdoor-unit terminals. Repeated thermal expansion and contraction can loosen wiring.
• Test-run heating mode: Before the first heating switch, run fan-only mode for 10 minutes, then switch to heating. Watch whether the airflow temperature is normal and whether there are unusual noises or smells.

2. Notes for Using Heating Mode

• Wait 3-5 minutes for the system to stabilize after startup; do not frequently turn the unit on and off.
• The airflow may feel cooler at the start of heating - this is the AC's cold-air-prevention design and is normal.
• Set the indoor temperature to 20-24 degrees C - comfortable and energy-efficient.
• Clean the filter regularly (every two weeks) to keep airflow smooth.

3. Maintenance Priorities by Venue

• Open offices: Densely occupied, so raise filter replacement to once every two weeks; regularly check supply vents for dripping.
• Meeting rooms and auditoriums: Used less often but for long stretches at a time; do a full deep clean before the season change so dust is not blown around with heating airflow.
• Server and equipment rooms: Precision AC running year-round needs continuous monitoring; at season change focus on filters and refrigerant pressure.

4. Gulin Commerce's Recommendation

Seasonal commercial AC maintenance looks small, but done well it reduces winter breakdowns, extends equipment life and cuts energy use. Suzhou Industrial Park Gulin Commerce Co., Ltd. sells commercial AC from brands including Midea, Gree, Haier and DAIKIN, and also provides AC installation, cleaning, maintenance and repair. For a professional on-site inspection or advice on selecting commercial AC, call 0512-68114680.