Preventive HVAC Maintenance Checklist for Property Managers

By Proair Air Conditioning Services, CSLB C-20 License #776028. Published October 30, 2026. Updated October 30, 2026.

The commercial HVAC maintenance checklist by interval

This schedule draws on a sample checklist for unitary and rooftop equipment published through the federal O&M Best Practices program at Pacific Northwest National Laboratory, plus ENERGY STAR contract guidance. Manufacturer instructions come first. Dusty sites and long operating hours call for shorter intervals.

What does California require you to keep on file?

Cal/OSHA's Title 8, Section 5142 covers mechanically driven HVAC systems that provide minimum building ventilation. It requires the system to be maintained and operated to deliver at least the outdoor air the building code required when the permit was issued.

• Inspect the HVAC system at least once a year, and correct problems in a reasonable time.
• Record each inspection or maintenance activity in writing: who did it, the date, the findings and the actions taken.
• Keep those records for at least five years.
• Make them available within 48 hours when Cal/OSHA, affected employees or their representatives ask.

The duty falls on employers, so a landlord, a tenant or both may hold it depending on the lease and who controls the system. Have your attorney confirm that. Outdoor air intakes, dampers and economizers deserve real attention here, because a stuck damper can quietly starve a building of fresh air.

What a useful log holds

• A number and roof-map location for every unit
• Make, model, serial, tonnage and refrigerant
• Filter sizes and quantities for each unit
• Readings from each visit, not only a checkmark
• Open issues, with a date for the fix

When a unit fails in a workplace

Two more rules bear on a stopped unit. Section 5142 says the system runs continuously during working hours, with exceptions that include scheduled maintenance and emergency repairs, so log why a unit was down. Title 8 Section 3396, the indoor heat rule, covers indoor work areas at 82°F or above with employees present. Its fuller controls start at 87°F, or 82°F for restrictive clothing or high radiant heat, and they include temperature records by date, time and location. Ask your safety advisor how this fits each tenant.

When should each visit land around South Gate?

Set the calendar by the local climate. Best Places estimates only about 9.6 days a year above 90°F for South Gate, yet highs reach the mid-90s and cooling demand runs into October.

How should you scope a maintenance contract?

ENERGY STAR warns that an owner can end up with a contract that provides too much or too little. It gives a plain example: outdoor coils in a particularly dirty environment may need cleaning two or three times a cooling season instead of once. Compare bids on the service promised, not only the monthly figure.

• Task list: each task, its frequency and which unit it covers.
• Materials: who supplies filters and belts, and what grade of filter.
• Records: a signed report after each visit, in a format your log can use.
• Exclusions: what counts as a billable repair instead of included work.
• Access: roof keys, ladders, escort rules and safe paths to each unit.
• Licensing: verify a C-20 license and the bond on the CSLB site before signing.

What should happen when a tenant reports a problem?

PNNL’s guidance treats discomfort, complaints and noise as possible signs of a performance problem, so give them a path into the log.

1. 1

   Log it

   Record the suite, the time, the complaint and who reported it.

2. 2

   Rule out the simple things

   Check the thermostat mode and setpoint, and look for blocked registers.

3. 3

   Match it to a unit

   Use the roof map to find which unit serves that suite.

4. 4

   Send the history

   Give the technician past complaints and the last readings for that unit.

5. 5

   Close it out

   Write down the cause, the fix and the date, then tell the tenant. A suite that keeps returning to the list needs a deeper look at airflow and controls.

What belongs on your seasonal plan?

Three items sit outside the routine table, and each one is easier to plan ahead than to handle in a rush.

Smoke events

EPA advises building operators to check whether systems can take a higher-efficiency filter, with MERV 13 or higher recommended during smoke events. It also suggests stocking filters ahead of time and adding a pressure gauge on at least one air handler, so you can see filters loading. Recirculation advice written for houses does not transfer directly to commercial systems, so plan this with your technician.

Refrigerant leaks

EPA rules set leak repair requirements for appliances with a full charge of 15 pounds or more of an HFC, with compliance from January 1, 2026. EPA has said it will reconsider the 2024 rule, so check current status. Record the full charge on each unit in your log, and keep every recharge and leak repair in writing.

Aging equipment

Use the log to spot the units that keep coming back. Repeated compressor faults, rusted cabinets and hard-to-find parts are the signal to start budgeting, and our rooftop unit replacement planning guide walks through the lead work. Plan it before the unit forces the decision.

What about apartments and mixed-use buildings?

Residential units add tenant rules. Civil Code 1941.1 lists heating among habitability items, and cooling is not on that list. California also requires carbon monoxide alarms in dwellings with fuel-burning appliances, so add alarm checks to your annual walk-through. Local rules are moving on indoor heat, so have counsel check what applies to each property.

What to check when a unit turns over

A vacant apartment is the easiest time to get at the equipment, so put these on the make-ready list.

• Fit a new filter and write the date on the frame.
• Run cooling and heating, and confirm the thermostat responds in both modes.
• Test the carbon monoxide alarm where the home has fuel-burning equipment.
• Look for stains on the ceiling below any attic unit, and check the drain pan.
• Photograph the nameplate and add it to the log.
• Tell the new tenant who supplies filters and how often to check the HVAC filter.

For more detail, see our pages on commercial HVAC maintenance, rooftop unit service and commercial repairs around South Gate and Bell Gardens.

A checklist only works if someone owns it

Give each building one owner for the log, one date for each visit and one list of open issues. The interval table says what to do, and the records prove it was done. If you want a technician to put real readings against that list, call us. We will check the units, explain what we find and give you the price before any work starts.