How to Reset Aircon After Power Outage: The 5-Minute Fix

🔌⚡ Power is back, but your aircon won’t start. Follow this step-by-step reset guide before calling a technician.

The power comes back after hours of loadshedding. You breathe a sigh of relief. You reach for the aircon remote, press the power button, and… nothing. No beep. No display. No cold air. Your aircon is dead.

Your heart sinks. “Did the power surge kill my aircon? How much is this going to cost?”

I’ve seen this panic thousands of times across South Africa. Loadshedding is hard on air conditioners. The sudden power loss, followed by the voltage surge when power returns, can trip breakers, blow fuses, and damage sensitive electronics.

But here’s the good news: most aircon not working after loadshedding problems are simple to fix. A tripped breaker. A turned-off isolator switch. A control board that needs resetting. These are free fixes you can do yourself in minutes.

In this guide, I’ll walk you through a step-by-step reset process for your aircon after loadshedding, explain the signs of surge damage, and tell you when to call a professional.

For more loadshedding guidance, check backup power guide and same-day repair services. Ready to revive your aircon? Let’s go.

⚡ Why Loadshedding Affects Your Aircon

Understanding what happens during loadshedding helps you diagnose problems:

What happens when power is cut: Your aircon loses power immediately. The compressor stops. The fans stop. The control board loses memory.

What happens when power returns (the danger zone): There’s often a voltage surge (spike) when power is restored. This surge can be 2-3x normal voltage for a few milliseconds. The surge can trip breakers, blow fuses, or damage sensitive electronics (PCB, capacitors).

Why aircons are vulnerable: Compressors draw high starting current. A surge during startup can damage windings. Control boards (PCBs) are sensitive to voltage spikes. Capacitors can fail from repeated surges.

Common loadshedding-related problems: Tripped breaker (most common). Turned-off isolator switch (some switches trip). Control board lock-up (needs reset). Failed capacitor. Burnt PCB components.

Read our loadshedding backup guide.

⚡ Step 1: Check and Reset the Breaker

This is the most common cause of air conditioner not starting after loadshedding. The power surge often trips the breaker.

What to do: Go to your electrical distribution board (fuse box). Find the breaker labeled “Aircon,” “HVAC,” “Outdoor Unit,” or similar. Is it in the “off” position or halfway between on and off? (that’s tripped). Flip the breaker fully to “off,” wait 10 seconds, then flip back to “on.”

Why this works: The power surge caused the breaker to trip as a safety measure. Resetting it restores power to your aircon.

If the breaker trips again immediately: DO NOT keep resetting it. This indicates a serious electrical problem (short circuit, faulty compressor, or damaged wiring). Call a professional immediately—this is a fire risk.

Pro tip: After resetting the breaker, wait 2-3 minutes before trying the remote. The control board needs time to initialise.

Read our circuit breaker guide.

🔌 Step 2: Check the Isolator Switch

The isolator switch (safety switch) near your outdoor unit can also trip during a power surge.

What to do: Go outside to the outdoor compressor unit. Find the isolator switch (small grey/white box with a red or yellow switch). Is it in the “off” position? Flip it to “on” (usually up).

Why this happens: Some isolator switches have surge protection that trips during voltage spikes. Gardeners, children, or maintenance workers may have accidentally turned it off.

Pro tip: After flipping the isolator switch, wait 2-3 minutes before trying the remote.

Read our aircon not turning on guide.

🔄 Step 3: Hard Reset the Aircon

Sometimes the control board (PCB) locks up after a power surge. A hard reset clears electronic glitches.

What to do: Turn off the circuit breaker for your aircon. Wait 5 FULL minutes (this allows capacitors to discharge and the control board to reset). Turn the breaker back on. Wait 2-3 minutes for the unit to initialise. Try the remote.

Why this works: The hard reset clears any corrupted memory in the control board. It’s like rebooting a computer after a crash.

Pro tip: Don’t shortcut the 5-minute wait. Less than 5 minutes may not fully discharge capacitors or reset the board properly.

Read our PCB problems guide.

📱 Step 4: Check the Remote Control

Sometimes the remote, not the aircon, is the problem after loadshedding.

What to do: Check if the remote display is blank—replace batteries. Use the smartphone camera test (point remote at camera, press button—see flashing light?). If no flashing, remote is dead. Clean the infrared LED (small dark bulb) with a soft cloth. Try the manual buttons on the indoor unit itself (if available).

Why this happens: Power surges can affect the remote’s electronics. Batteries may have been drained by the outage. The remote’s memory may have been lost.

Pro tip: If the manual buttons work but the remote doesn’t, the remote is the problem. Buy a universal replacement (R150-R400).

Read our remote not working guide.

⏰ Step 5: Check Timer and Sleep Mode

Loadshedding can scramble the timer settings on your aircon, causing it to stay off.

What to do: Look at the remote display for timer icons (clock symbol, “TIMER ON/OFF,” or “SLEEP”). Press the “Timer” or “Cancel” button repeatedly until all timer icons disappear. Press and hold the “Cancel” or “Clear” button for 3-5 seconds. Remove batteries from the remote for 30 seconds to clear memory.

Why this happens: Power loss can corrupt the timer memory. The aircon may think it’s supposed to be off.

Read our sleep settings guide.

⚠️ Signs of Power Surge Damage

If the reset steps didn’t work, your aircon may have power surge damage. Look for these signs:

Burning smell from indoor or outdoor unit: Indicates electrical component failure. Turn off the breaker immediately. Call a professional. Fire risk.

Breaker trips repeatedly after reset: Short circuit in compressor, fan motor, or control board. Do not keep resetting. Call a professional.

Unit has power (display lights) but won’t respond: Control board (PCB) may be damaged. Needs professional diagnosis.

Humming sound but compressor won’t start: Capacitor may be damaged. Common after surges. Capacitor replacement: R500-R1,000.

Error codes on display: Write them down. The control board may be misreading sensors or detecting surge damage.

Unit works but cooling is poor: Low refrigerant (unlikely from surge) or damaged compressor. Professional diagnosis needed.

Read our capacitor failure guide and PCB problems guide.

🛡️ How to Protect Your Aircon from Loadshedding

Preventing aircon tripping after power outage is cheaper than repairing surge damage:

Install a surge protector (R500-R1,500): The single most important protection. A dedicated aircon surge protector or whole-home surge protector absorbs voltage spikes. Cheap insurance against R5,000-R12,000 compressor replacement.

Turn off the aircon before loadshedding starts (if you know the schedule). If you know loadshedding is coming, turn off the aircon at the remote AND the isolator switch. This prevents the surge from affecting the unit when power returns.

Install a voltage stabiliser (AVR) (R2,000-R5,000). Protects against both over-voltage and under-voltage (brownouts). More expensive but more comprehensive protection.

Consider a UPS or inverter for critical units. For home offices, medical equipment, or bedrooms, a UPS (R3,000-R8,000) keeps the aircon running during short outages.

Install a hard start kit (R500-R1,000). Helps the compressor start more reliably after power returns. Not a surge protector but reduces startup stress.

Annual professional service (R500-R800). A technician can check for early signs of surge damage and replace failing components before they cause failure.

Read our loadshedding backup guide and generator guide.

Read Eskom loadshedding schedules and ECASA surge protection standards.

📞 When to Call a Professional

Call a professional immediately if:

• You’ve completed all 5 reset steps and the aircon still doesn’t work. Don’t keep trying—you may damage it further.
• The breaker trips repeatedly after reset. This is a fire risk. Do not keep resetting.
• You smell burning or see smoke. Turn off the breaker and call immediately.
• You hear loud grinding or banging noises. Major mechanical failure.
• The outdoor fan runs but no cold air. Compressor or refrigerant problem.
• You see visible damage (burnt wires, melted plastic). Do not touch—call a professional.

What to tell the technician: “My aircon stopped working after loadshedding. I’ve tried resetting the breaker, isolator switch, and hard reset. There’s [no burning smell / a burning smell]. The breaker [trips / stays on]. The display shows [error code if any].”

Read our same-day repair guide.

❓ Frequently Asked Questions

✅ Final Thoughts: Reset First, Don’t Panic

When your aircon is not working after loadshedding, it’s easy to panic and assume the worst. But 80% of cases are solved by resetting the breaker, checking the isolator switch, or performing a hard reset. These fixes cost nothing and take 5 minutes.

Key takeaways for loadshedding-related aircon problems:

• Reset the breaker first – #1 cause. Free fix.
• Check the isolator switch – often tripped or turned off. Free fix.
• Hard reset (breaker off for 5 minutes) – clears control board glitches. Free fix.
• If the breaker trips repeatedly, call a professional – fire risk. Don’t keep resetting.
• Burning smell = turn off immediately – fire risk. Call a professional.
• Install a surge protector – R500-R1,500 prevents R5,000-R12,000 damage.
• Turn off the aircon before loadshedding starts – best prevention.

Your action plan: First, reset the breaker and check the isolator switch. Second, perform a hard reset (breaker off for 5 minutes). Third, check the remote batteries and timer settings. Fourth, if still not working, look for signs of surge damage (burning smell, repeated tripping). Fifth, request quotes from local technicians for professional diagnosis and surge protection installation.