Stormproof Your HVAC System

By Bridget Coila

March 31, 2025

Heavy rain, intense winds and power outages can leave your HVAC unit battered and broken, but protecting your system now helps you prepare for oncoming storms. Knowing how to stormproof your HVAC system keeps your air conditioner and heater functioning no matter how wild the weather gets.

This May Also Interest You: HVAC Terms Every Homeowner Should Know

Are HVAC Systems Vulnerable During Storms?

Powerful storms can affect various parts of your HVAC system, but outdoor air conditioner units are particularly vulnerable. If your outdoor AC isn't anchored, strong winds could knock it over or even move it across the yard. Internal components might get damaged, and the electrical and refrigerant lines could get disconnected. Flying debris also poses a danger to your outdoor AC unit, particularly during tornadoes or hurricanes.

Heavy rain that causes flooding might submerge the unit, which could damage the motor and internal wiring. Hail might strike sensitive components of the condenser, breaking the coils that cool air flowing through the unit.

Power surges are another concern during storms. Lightning strikes, power line damage caused by falling branches and storm-caused transformer blowouts can all cause a damaging power surge that destroys delicate electronics inside your HVAC unit.

How to Stormproof HVAC Systems Before a Storm Hits

Stormproofing involves figuring out ways to prevent potential damage and adding buffers that keep your HVAC system safe. Here are some tips for HVAC protection before a storm.

Anchor and Elevate Your Outdoor AC

Most central air conditioners and mini-split systems have an outdoor unit that should be anchored to prevent toppling during storms. If possible, elevate the unit on a platform or concrete pad for added flood protection.

Shut Off Your HVAC System

Turning everything off before the storm hits helps protect your system from a power surge. In addition to power surge protection, shutting off your AC and heater helps reduce the risk of electrical issues that might lead to a fire.

Inspect Your HVAC Unit Before the Storm

Clear away any debris around the outdoor unit that might impede airflow, and visually inspect the coils and exterior for potential damage. Regular maintenance ensures your HVAC is operating at top capacity before high winds and rain hit.

Cover Your Outdoor AC Unit

A waterproof AC cover or heavy tarp can keep heavy winds and flying debris from damaging the unit. For even more protection during hurricane season, consider installing a protective steel HVAC cage around the outdoor unit.

Install a Surge Protector

Safeguard your system from unexpected electrical surges by installing a surge protector. Choose a surge protector specifically designed for HVAC systems or a whole home surge protector that also covers your interior electrical system.

Include Your AC in Hurricane Readiness Plans

Hurricanes often cause heavy flooding, especially in coastal or flood-prone areas. If you're using sandbags to keep water out of your home, remember to also put some around your AC unit.

More Related Articles:

How Do You Protect Your HVAC Systems During Storms?

Sometimes, a storm strikes before you've had a chance to implement your severe weather prep plan. Turn off your HVAC system if it's still running, and wait until the storm is over and you've had a chance to inspect everything before turning it on again.

Emergency HVAC Tips for Dealing With a Storm's Aftermath

If your home has been hit by a storm and you notice signs of damage to your HVAC unit, the first thing to do is contact your home insurance company. Avoid using your AC and heater until a professional has inspected everything to make sure there's no damage. Hidden electrical problems could cause a shock, so practice good air conditioning safety during storm recovery.

If your HVAC system is undamaged but you don't have power, you might be able to hook the unit to a backup generator to cool or heat your home. Check the generator to ensure it can support the power load your HVAC unit requires. When you turn the HVAC unit on, the initial load is typically higher than the regular operating load, so your generator needs to support both levels of energy usage. A smaller portable generator might not support a whole home HVAC system, but you might be able to use it with a window air conditioner to get cool air flowing in one room.

Follow us