Hurricane Season HVAC Checklist: Before, During and After the Storm

Published October 16, 2026 · Reviewed October 16, 2026

Part of our Residential HVAC Services guides.

Why should hurricane prep include your HVAC system?

Hurricane prep should include your HVAC system because the biggest storm risks to a Greater Houston home's comfort and safety are long power outages in extreme heat and floodwater reaching equipment. The Atlantic hurricane season runs June 1 through November 30, which overlaps the hottest months of the year.

Recent storms show both risks. Hurricane Beryl made landfall on July 8, 2024, and CenterPoint Energy reported that peak outages reached an estimated 2.26 million of its Houston Electric customers. The Associated Press counted at least 36 Texas deaths linked to Beryl by July 25, 2024, including people who lost power during the heat. Seven years earlier, Hurricane Harvey flooded 154,170 homes in Harris County, according to the Harris County Flood Control District's final report, including 9,450 homes in the Cypress Creek watershed that runs through the Spring area.

The safest HVAC decisions in a hurricane are mostly about what not to touch.

What should you do to your HVAC system before a storm?

Before a storm, get the system in good working order, clear the area around the outdoor unit, document your equipment and plan for an outage. Work through this list early in the season and again when a storm is forecast:

1. Schedule maintenance early. A system with a clean coil, a clear drain and sound electrical parts is more likely to restart cleanly after an outage. A spring tune-up does double duty here.
2. Clear the yard around the outdoor unit. Bring in or tie down furniture, planters, grills and toys that wind could throw into the coil. Ready.gov also advises de-cluttering drains and gutters.
3. Find your shutoffs. Know where the breaker for the HVAC system is in your panel and where the outdoor disconnect box sits next to the condenser, so you can tell a technician or an electrician later.
4. Photograph your equipment. Take pictures of the outdoor unit, the indoor unit and their nameplates (model, serial, refrigerant type). They help with insurance claims and service calls after the storm.
5. Check carbon monoxide detectors. Ready.gov advises installing working carbon monoxide detectors on every level of your home. If you plan to use a generator, this is essential.
6. Change the filter so the system is not starting from a loaded filter if power is out for days.
7. Cool the house down while you still have power, and close blinds on sunny windows to slow the heat gain once it goes out.
8. Plan for heat. Decide where vulnerable family members will go if the power stays out in July or August heat.

What should you do with your AC during the storm?

During the storm, stay inside, stay away from the outdoor unit and protect the system from power surges. Ready.gov notes that power may return with momentary surges or spikes and advises disconnecting appliances and electronics to avoid surge damage. For central HVAC, the practical step is to set the thermostat to off when the power starts flickering or goes out, then restore it once power is steady.

If floodwater is rising toward your home, Ready.gov advises turning off the electricity at the main breaker or fuse box only if it is safe to do so. Never touch electrical equipment if it is wet or if you are standing in water.

What should you check on your HVAC system after the storm?

After the storm, look before you switch anything on, and look from a safe distance. Check for these:

• Debris on top of, inside or against the outdoor unit.
• A unit shifted or knocked off its pad, or refrigerant lines that are bent or crushed.
• A water line or mud on the outdoor unit, the indoor unit, the furnace or air handler, or the ductwork.
• Damaged wiring, a damaged disconnect box, or a meter or electrical panel that took water.

If everything looks undamaged and dry, clear light debris from around the unit by hand, then turn the thermostat back to cool once power is stable. If the system still won't start, the guide to an AC that won't turn on after a power outage walks through the safe checks.

If you see damage, or if any part of the system was in floodwater, do not turn it on. Call a licensed HVAC technician, and an electrician if your electrical service was affected.

Is flood-damaged HVAC equipment safe to use?

Flood-damaged HVAC equipment is not safe to use until a licensed professional has inspected it, and it often needs to be replaced rather than repaired. The International Code Council's Building Safety Journal notes that when HVAC equipment is submerged, motors, fans, circuit boards, insulation and ductwork can be damaged beyond repair, that hidden damage can pose safety risks even when components appear to work, and that post-flood protocols should include inspection by a licensed professional.

For homeowners, that means:

• Do not run an outdoor unit, air handler, furnace or heat pump that sat in floodwater, even if it seems to power up.
• Do not open electrical panels, disconnect boxes or equipment cabinets yourself.
• Do not touch refrigerant lines or try to drain or vent refrigerant. Under EPA rules, intentionally venting refrigerant is prohibited, and servicing refrigerant-containing equipment requires a certified technician.
• Treat flooded ductwork as suspect too; it can hold contaminated water and debris.
• Photograph the water line and the equipment before anything is removed, for your insurance claim.

How do you use a generator safely with your HVAC system?

A portable generator must run outdoors only, at least 20 feet from windows, doors and attached garages, according to Ready.gov. Carbon monoxide from a generator can build to dangerous levels quickly, and Ready.gov's guidance to keep working CO detectors on every level of the home applies whenever a generator is running.

• Never run a generator in a garage, carport, porch, shed or crawlspace, even with the door open.
• Never plug a generator into a wall outlet to power the house. Connecting a generator to your home's wiring, including to run a central air conditioner, is work for a licensed electrician using the proper transfer equipment.
• Many portable generators are too small to start and run a central AC system. Ask an electrician to size any generator meant to run HVAC.
• Smaller loads, such as fans and a window unit, are a more realistic use of a portable generator.

What records should you keep for storm season?

Keep a storm-season file with your equipment photos and nameplates, your most recent maintenance report and any post-storm inspection notes. Insurers and technicians both work faster when they can see what the system looked like before the storm, how old it is and what refrigerant it uses. If a storm leaves you deciding between repairing and replacing damaged equipment, those records make the comparison easier.

For routine pre-season service, see what happens during an AC tune-up.

Frequently Asked Questions

Should I turn off my AC during a hurricane?

Setting the thermostat to off when power starts flickering or goes out helps protect the system from surges when power returns. Ready.gov notes that restored power can come with momentary surges or spikes. Turn the system back on once power is steady and you have checked the outdoor unit for damage from a safe distance.

Can I run my AC if the outdoor unit was underwater?

No. Do not run any HVAC equipment that sat in floodwater until a licensed professional has inspected it. The International Code Council notes that submerged HVAC components can be damaged beyond repair and that hidden damage can pose safety risks even when the equipment seems to work.

Should I cover my outdoor AC unit before a hurricane?

The more important step is clearing loose objects that wind could throw into the unit. If you do cover the unit to keep debris out, never run the system with any cover on it, and remove the cover before turning the AC back on.

How far from the house should a generator be?

Ready.gov advises running generators outdoors only, at least 20 feet from windows, doors and attached garages. Never run a generator in a garage or other enclosed space, and keep working carbon monoxide detectors on every level of the home.

Can a portable generator run my central air conditioner?

Many portable generators are too small to run a central air conditioner, and connecting any generator to your home's wiring is a job for a licensed electrician with proper transfer equipment. Never plug a generator into a wall outlet. Fans or a window unit are more realistic loads for a portable generator.

When is hurricane season in Houston?

The Atlantic hurricane season runs from June 1 through November 30. That overlaps Houston's hottest months, which is why long outages after storms like Hurricane Beryl in July 2024 became heat emergencies.

Sources

1. Ready.gov — Hurricanes — June 1–November 30 Atlantic season, clearing drains and outdoor items, turning off electricity if safe (as of October 16, 2026)
2. Ready.gov — Power Outages — generators outdoors at least 20 feet from windows, doors and attached garages; CO detectors; surge protection (as of October 16, 2026)
3. Ready.gov — Floods — do not touch wet electrical equipment or stand in water (as of October 16, 2026)
4. CenterPoint Energy Form 10-Q, quarter ended June 30, 2024 (SEC) — Beryl peak outages of an estimated 2.26 million Houston Electric customers (as of October 16, 2026)
5. Associated Press via ABC News — Texas deaths from Hurricane Beryl climb to at least 36 (July 25, 2024) — Beryl death toll including heat-related deaths (as of October 16, 2026)
6. Community Impact — Hurricane Harvey damage report, Harris County (June 8, 2018) — 154,170 Harris County homes flooded, per the Harris County Flood Control District (as of October 16, 2026)
7. Harris County Flood Control District — Cypress Creek — 9,450 homes flooded in the Cypress Creek watershed during Harvey (as of October 16, 2026)
8. International Code Council, Building Safety Journal — Flooded and Failing (April 28, 2025) — flood damage to HVAC components, replacement vs. repair, licensed inspection (as of October 16, 2026)
9. U.S. EPA — Section 608 of the Clean Air Act — prohibition on intentionally venting refrigerants; technician certification (as of October 16, 2026)