What to Do During an HVAC Emergency

HVAC emergencies rarely happen at a convenient time. A furnace quits on the coldest night of the year, an AC unit fails during a summer heat wave, or a commercial system goes down in the middle of a busy workday — and even with the fastest response time, there’s almost always a gap between the moment you call for help and the moment a technician arrives.

That waiting period doesn’t have to be wasted time. There are practical steps you can take — and some important things to avoid — that can protect your property, limit damage, and keep things as manageable as possible until your HVAC technician gets there.

At Level One HVAC, we field emergency calls around the clock, and we often walk customers through exactly these steps over the phone while help is on the way. Here’s what we recommend.

First: Assess for Safety Issues

Before anything else, make sure the situation is actually safe. Some signs mean you should stop troubleshooting and prioritize safety immediately:

Smell of gas — leave the building immediately, don’t operate any electrical switches (including light switches) on your way out, and call your gas utility’s emergency line from a safe distance before calling for HVAC service
Burning smell or visible smoke from any HVAC equipment — shut off power to the unit if it’s safe to do so, and evacuate if smoke is significant
Carbon monoxide alarm sounding — evacuate immediately and call 911; this takes priority over everything else
Water actively flooding from equipment — shut off the water supply to the unit if you can safely access the shutoff valve

If any of these apply, address the safety issue first. Everything else in this guide assumes the situation is uncomfortable or inconvenient, but not an active safety hazard.

If Your Heating System Fails

Do:

Layer up and use safe alternative heat sources if needed — extra blankets, warm clothing, or a space heater used properly (plugged directly into a wall outlet, not an extension cord, and kept clear of anything flammable)
Close off unused rooms or areas to concentrate warmth where it’s needed most
Open cabinet doors under sinks on exterior walls to help prevent pipes from freezing if the outage is extended
Let faucets drip slightly if temperatures are dangerously low and the outage may last several hours, to reduce the risk of frozen pipes
Keep your thermostat set to “on” rather than “auto” for the fan, if your system allows it, to keep some air circulating

Don’t:

Use an oven or stove as a heat source — this is a serious carbon monoxide and fire risk
Overload a single circuit with multiple space heaters
Ignore dropping temperatures in a commercial or multi-family building — check on vulnerable areas like unoccupied units, stairwells, or storage areas where pipes could freeze unnoticed

If Your Cooling System Fails

Do:

Close blinds and curtains during the hottest parts of the day to reduce heat gain
Use fans to keep air moving, even without air conditioning — moving air feels noticeably cooler
Stay hydrated and watch for signs of heat-related illness, especially in older buildings, facilities with vulnerable populations, or extreme heat conditions
Close off unused rooms to reduce the area you need to keep cool
Move sensitive equipment, inventory, or materials away from direct sun or areas prone to heat buildup if the outage may be extended

Don’t:

Prop doors open in an attempt to bring in cooler air unless outdoor temperatures are genuinely cooler than indoor temperatures — this often makes things worse, not better
Ignore signs of heat stress among employees, tenants, or customers — extreme heat is a genuine health and safety concern, not just a comfort issue

For Commercial and Facility Settings

If you’re managing a commercial building, restaurant, retail space, or multi-tenant property, a few additional steps help minimize disruption:

Communicate with tenants, employees, or customers early. A short, clear message about the situation and expected timeline goes a long way toward managing frustration.
Identify priority areas. If certain zones matter more than others — a server room, a walk-in cooler, a space with vulnerable occupants — let the technician know this when you call, so they can prioritize accordingly upon arrival.
Check backup systems. If your facility has redundant equipment or backup units, this is the time to verify they’re functioning and can be brought online if needed.
Document the issue. Note when the problem started, any unusual sounds or smells beforehand, and error codes displayed on equipment. This information helps your technician diagnose the issue faster once they arrive.

What NOT to Do While You Wait

Don’t attempt DIY electrical or gas repairs. HVAC systems involve high-voltage electrical components and, in many cases, gas lines. Attempting a repair without proper training risks injury, further equipment damage, and can create dangerous conditions.

Don’t repeatedly cycle the system on and off. If a system has failed, continuing to try restarting it can sometimes cause additional damage, particularly to compressors and motors that may already be struggling.

Don’t ignore small water leaks. Even a minor leak from HVAC equipment can cause meaningful water damage if left unaddressed for hours. Place towels or a container under any active leak and, if safe, shut off water supply to the affected equipment.

Don’t wait to call. The sooner you call for emergency service, the sooner you’re in the queue — waiting to see if the problem resolves on its own usually just extends your wait time unnecessarily.

Helping Your Technician Help You Faster

A few small things can speed up the actual repair once your technician arrives:

Clear access to the equipment (mechanical rooms, rooftop access, attic access, etc.)
Have any recent service history or equipment information available if you have it
Be ready to describe exactly what happened, including any sounds, smells, or warning signs beforehand
Keep pets secured and clear a safe path to the equipment

When Every Minute Counts, You Want a Team That Answers

HVAC emergencies are stressful, but knowing what to do — and what to avoid — while you wait can make a real difference in comfort, safety, and even the extent of any damage. At Level One HVAC, our emergency service team is available 24/7, 365 days a year, because we know HVAC problems don’t wait for convenient timing.

Facing an HVAC emergency right now? Contact Level One HVAC’s emergency service line — we’re here around the clock to get your system back up and running.

Level One HVAC Services, Inc.

Serving all of Michigan

Toll Free: 844-616-4822

Grand Rapids: 616-616-4822

New Hudson: 248-486-6500

West Branch: 989-999-4822