Symptom
AC won't turn on?
When an air conditioner won't turn on at all, the cause is usually power, the thermostat, a safety switch that has shut the system off (often a full condensate drain), or a failed electrical component such as a capacitor or contactor. Check the thermostat and the breaker once. If it still won't start, it needs a technician.
Soon. In summer a dead system gets uncomfortable fast. If the house is heating up and someone at home is vulnerable to heat, call — emergency service runs 24/7.
What usually causes this.
These are the common possibilities, not a diagnosis. A page cannot tell which one it is — that takes a technician testing the system.
- Outdoor unit
- Power
- Thermostat
- Drain
- Thermostat
- Dead batteries, the wrong mode, a schedule overriding your setting, or a blank screen can all stop the system from being called on at all.
- Tripped breaker or disconnect
- The indoor and outdoor units usually have separate breakers, and there is a disconnect switch next to the outdoor unit. A breaker that trips repeatedly points to an electrical fault.
- Condensate float switch
- Many systems have a switch that shuts everything off when the condensate drain backs up, to stop water damage. In a humid climate this is one of the most common reasons a system suddenly stops.
- Failed capacitor or contactor
- These start and switch the outdoor unit. When one fails, the outdoor unit may hum, click or do nothing.
- Control board, wiring or a safety limit
- A failed board, damaged low-voltage wiring (sometimes from pests or yard work), or a tripped safety control can keep the system off.
What you can safely check.
- Check the thermostat: screen on, set to Cool, set point a few degrees below room temperature. Replace batteries if it uses them.
- Check the breakers for the indoor and outdoor units. If one has tripped, reset it once. If it trips again, leave it off and call.
- Make sure the furnace or air handler door is fully closed — many have a safety switch that keeps the system off when the panel is loose.
- Look near the indoor unit for water in the drain pan or on the floor, which suggests the float switch has shut the system down.
Leave these alone
- Resetting a breaker more than once — a repeat trip is a warning, not a nuisance.
- The outdoor unit's electrical panel, capacitor and contactor.
- Bypassing a float switch to get the system running — it's there to prevent water damage.
Call rather than book online if:
- The breaker trips again after one reset
- You smell burning, or see scorch marks near either unit
- Water is spreading from the indoor unit or through a ceiling
What we check when we get there.
In order, and every time — the point of a diagnostic is to find out which cause it is before anything is replaced.
- 01A technician confirms power and the thermostat call, then works through the safety circuit — float switch, door switch, limits — to find what is holding the system off.
- 02If the outdoor unit is the problem, the capacitor, contactor and compressor are tested rather than replaced on a guess.
- 03If a blocked drain tripped the float switch, the drain is cleared and checked so it doesn't happen again next week.
What it is likely to cost.
Many no-start problems are small repairs — a capacitor, a contactor, a cleared drain. A control board or compressor costs more. The diagnostic price is given before the visit, and the repair price before any work.
- Diagnostic / service call
- $89
- Capacitor replacement
- From $179
- Contactor replacement
- From $189
- Condensate drain clearing
- From $149
- Control board
- $449–$899
- Basic thermostat replacement
- From $199
Prices are starting points for standard work in the Savannah area. Final price depends on the system and site, and is confirmed before work begins. Permits and code-required upgrades may be additional.
Questions people ask about this.
- The thermostat is blank. Is the AC broken?
- Not necessarily. Replace the thermostat batteries if it has them and check the breaker for the indoor unit. Some thermostats are powered by the system itself, so a tripped float switch or blown fuse can make the screen go blank too.
- The outdoor unit hums but the fan doesn't spin. What does that mean?
- Often a failed capacitor or a stuck fan motor. Switch the system off at the thermostat — running it this way can overheat the compressor — and schedule service.
- Can a clogged drain really shut the whole AC off?
- Yes. The float switch is designed to do exactly that so the drain pan doesn't overflow into the house. Drains clog more often in humid climates because the system removes so much water.
Work out the decision:Seasonal Checklist
Further reading:Hurricane season and your HVAC: before, during and after a storm
The service that fixes it.
Air Conditioning Repair is the work behind this symptom. Its page covers what is involved, how it is quoted and what we stand behind.
Symptoms that sit next to it.
Systems rarely fail in one way only. If one of these is also true, say so when you book — it narrows the diagnosis before anyone arrives.
Air conditioner not cooling, not starting, freezing up, leaking or making noise.
- AC running but not coolingAn air conditioner can run without cooling properly when airflow is restricted, the indoor coil has frozen, a component has failed, or the refrigerant charge is low because of a leak.
- AC frozen / iced upIce on an air conditioner's copper lines or indoor coil almost always means the coil is getting too cold — usually because airflow across it is restricted, or because the refrigerant charge is low from a leak.
- AC leaking waterAn air conditioner leaking water indoors is usually a blocked condensate drain, an overflowing or cracked drain pan, or a frozen coil melting.
- Outdoor unit not runningIf the indoor fan is blowing but the outdoor unit isn't running, the house gets moving air without cooling.
- AC making a noiseA new noise from an air conditioner usually points to a specific part.
Not sure which it is?Describe it to the assistant
Everything else we are called about.
The whole index, in three groups.
HUMIDITY, AIRFLOW & ENERGY BILLS
House feels humid or dampSome rooms too hot or coldPower bill suddenly higher
Get it looked at.
We cover Savannah, the Coastal Empire and the South Carolina Lowcountry. Tell us what the system is doing — you do not need to know the cause. The diagnostic price is given to you before the visit, and the repair price before any work starts.
No heat, or no cooling at all?Call rather than send a request — (912) 858-3737 is answered around the clock.