Although air conditioning is indispensable on hot days, HVAC (Heating, Ventilation and Air Conditioning) experts warn that using it during summer storms can lead to costly damage.
Risks include lightning, power surges, flooding and wind-blown debris, which can severely damage the appliance’s electrical system and components, according to The Spruce.
Danny Pen, president of New Era Plumbing & HVAC, recommends turning off the appliance completely when a storm approaches.
The HVAC specialist states that if thunder and lightning are seen and heard nearby, the air conditioner should be turned off at the thermostat and power should be turned off at the electrical panel.
Pen points out that even surge protection doesn’t guarantee the device’s safety during a storm.
Leaving the air conditioner on does not necessarily mean that it will break down, but it significantly increases the risk of breakdowns.
Overvoltages can damage the compressor, one of the most expensive components of the system, and in some cases can affect the entire appliance and even other connected devices in the home. Windblown debris or water build-up can block airflow or hit sensitive components, causing additional damage.
HVAC instructor Anthony Weinburg explains that power surges can generate heat spikes that melt components like the condenser, compressor or control panel. Damage can also affect the thermostat or the electronic board of the boiler, which leads to expensive repairs.
Experts say there is no safe setting for air conditioning during storms.
“Fan” mode does not reduce the risk of overvoltage
The reason why the device must be turned off is not related to attracting lightning, but to protect the electrical installation from the effects of a possible impact nearby.
“Fan” mode does not reduce risks, experts say.
Before a storm, experts recommend setting the thermostat a few degrees lower to cool the home in advance. After the appliance is turned off, the outdoor unit can be covered with a tarp or protective plate to prevent debris from hitting it. After the storm has passed, the appliance should be visually inspected and debris removed. If the area has been flooded, a technician check is required before restarting.
Other situations where the air conditioner should be turned off
The appliance must not be used when the outside temperature drops below 15°C, as the evaporator may freeze. It is also recommended to turn off the AC during wildfires or on days with intense smog, to avoid the introduction of polluted air into the home.
In the event of a power failure, the device must be turned off to prevent damage from surges that may occur when power is restored.
