Why Won’t My AC Turn On After a Storm in Spring Hill?
You had a storm come through. Lightning, thunder, maybe the power flickered a few times or went out completely. Now the storm is over, the power is back and the AC is not turning on. The house is already starting to warm up and you have no idea what happened or where to start.
This is one of the most common calls we get in Spring Hill during summer storm season and the good news is that a lot of the time the fix is straightforward. Here is what to check before you call anyone and what it means if none of those things work.
Start With the Breaker
The first thing to check is the breaker panel. Power surges during storms trip breakers regularly and an AC that will not turn on after a storm is almost always worth checking the breaker before anything else. Find the breaker labeled for the AC or air handler, which is usually a double breaker, and look at whether it has tripped to the middle position. If it has, switch it all the way off first and then back on. Do not just push a tripped breaker back to on without switching it off first or it may not reset properly.
If the breaker trips again immediately after you reset it do not keep resetting it. A breaker that trips repeatedly is telling you something in the circuit is drawing more current than it should. That is a different problem from a simple surge trip and it needs a technician. Repeatedly resetting a breaker that keeps tripping can damage the compressor. If you have been dealing with a breaker that keeps tripping on its own that pattern needs attention regardless of whether a storm started it.
Check the Disconnect Box at the Outdoor Unit
There is a disconnect box mounted on the wall near the outdoor condenser unit. It is usually a gray or beige box with a pull-out fuse block inside. During a power surge or a lightning strike nearby the fuses in that box can blow even when the main breaker is fine. Pull the fuse block out and look at the fuses. If they look burned, blackened or the element inside is visibly broken they need to be replaced. This is a relatively inexpensive fix but it does require someone who knows what they are doing to replace them safely.
Check the Thermostat
Power outages and surges can reset or confuse thermostats, especially smart thermostats and digital ones. Check that the thermostat is set to cool, that the temperature is set below the current room temperature and that it has power. If the display is blank the thermostat may have lost its settings or the batteries may have died during the outage. Replace the batteries if it runs on them and see if the system responds.
Some thermostats have a built in delay after a power interruption to protect the compressor. This delay can be anywhere from three to five minutes. If the thermostat looks fine and is set correctly wait a few minutes before assuming something is wrong with the system itself.
Give the System Time Before You Panic
Most AC systems have a built in time delay that prevents the compressor from restarting immediately after power is restored. This protects the compressor from starting under full load too quickly after a power interruption. The delay is usually between three and five minutes but on some systems it can be longer. If the power just came back on and the AC has not started yet wait at least five minutes before checking anything else.
If you had a more serious outage and the system shut off suddenly without warning before the power went out that is worth paying attention to when you call.
When the Checks Do Not Fix It
If the breaker is fine, the disconnect fuses are intact, the thermostat is set correctly and the system has had time to restart but still will not turn on, the storm likely caused damage to a component inside the system. A power surge can take out a capacitor, a contactor, a control board or in a direct lightning strike scenario the compressor itself. These are not things you can diagnose or fix without the right equipment and they should not be left to sit in Florida’s summer heat hoping the problem resolves on its own.
A capacitor failure from a surge is one of the more common storm related repairs and it is a relatively straightforward fix for a technician. A damaged control board is more involved. Either way you need someone to come out and find the actual cause before you can get the system running again.
Frequently Asked Questions
Should I reset the breaker more than once if the AC still won’t turn on?
Reset it once. If the breaker trips again immediately or the system still does not respond after resetting, stop there. Repeatedly resetting a tripping breaker can damage the compressor and turn a manageable repair into a much more expensive one.
How long should I wait for the AC to turn on after power comes back?
Give it at least five minutes. Most systems have a built in delay to protect the compressor after a power interruption. If it has not started after five to ten minutes the delay is not the issue and something else is going on.
Can a power surge damage my AC permanently?
It depends on what the surge hit. A surge that takes out a capacitor or a contactor is a fixable repair. A direct lightning strike that damages the compressor or the control board is more serious. A technician needs to diagnose what was actually affected before you can know the scope of the repair.
Is there anything I can do to protect my AC from storm damage in the future?
A whole home surge protector installed at the panel is the most effective protection against power surges damaging your AC and other major appliances. It will not protect against a direct lightning strike but it significantly reduces the risk of surge related component failures during the kind of summer storms Spring Hill gets regularly.
What if the outdoor unit is making a strange noise but won’t fully start?
That is usually a capacitor or contactor issue. The system is trying to start but does not have what it needs to complete the startup sequence. Turn the system off at the thermostat and call a technician. Running a system that is struggling to start puts additional wear on the compressor.
What to Do If None of That Works
Spring Hill gets hit with afternoon thunderstorms from June through September and your AC taking a hit from a surge or an outage is not unusual. Most of the time it is something straightforward. But if you have worked through everything above and the system still will not turn on, it needs a technician. The longer a damaged system sits in Florida’s summer heat the worse the house gets and the more wear any struggling components take trying to restart.
Spring Hill Air Conditioning handles AC repair throughout Hernando County. Call us and we will come out, find the actual cause and get the system running again.