There is a useful distinction to make in the first minute. An AC that starts but does not cool is a cooling problem. An AC that does nothing at all — no beep when you press the remote, no light on the indoor unit, no fan — is almost always a power problem, and power problems live outside the machine far more often than inside it.
So work the chain in order: supply, MCB, socket, stabiliser, remote, unit. Every step in that list except the last is free to check and takes a minute. Skipping them is how people end up paying for a board that was never faulty.
This page walks that chain, explains the two protection behaviours that make a healthy AC look dead, and is clear about where the checks stop and a professional starts.
A note first. XpertWorker is a marketplace, not a service company. We do not set any professional’s price and we never charge you a paisa. Every professional quotes you free before starting, and you pay them directly.
In this guide
Work down the power chain, in this order
Do not skip a step because it seems too obvious. The obvious ones are the ones that turn out to be the answer.
- 1. Is the rest of the house live? Lights on, fan running, other sockets working. In many parts of Delhi NCR a partial supply failure or a single phase out can leave some circuits alive and others dead, so check more than one room.
- 2. Look at the MCB for the AC. Go to the distribution board and check whether the AC breaker has tripped. Switch it back on once. If it holds and the AC starts, note that it tripped, because that is a fault worth understanding — our guide on the AC that trips the MCB covers what the timing tells you. If it trips again immediately, stop and call an electrician.
- 3. Check the wall switch and the socket. Many ACs run from a dedicated switched socket that somebody may have switched off while cleaning. Test the socket by plugging in a lamp or a phone charger. If the socket is dead, the AC is not your problem.
- 4. Look at the plug top and the cable. From the outside only. A discoloured, melted or warm plug top, or a burnt smell at the socket, means switch off at the MCB and call an electrician — do not plug it back in to see whether it works.
- 5. Check the stabiliser, if there is one. Is its display or indicator lit? Many stabilisers cut the output entirely when the incoming voltage falls outside their range, and they hold that cut-off until the supply recovers. A dead-looking AC with a stabiliser showing a fault or cut-off light is a supply story, not a machine story.
- 6. Rule out the remote. Press the small manual or auto button under the front flap of the indoor unit. If the AC starts, the machine is alive and your fault is in the remote. Our guide on the AC remote that is not working has the two-minute tests.
If everything in that list checks out and the unit is still completely dead, then and only then is it time to call someone.
Want a real quote for your own job?
Get free quotesTwo reasons a healthy AC looks dead
Both of these are the unit protecting itself, and both get misread as a failure.
- The restart delay. Most ACs refuse to start the compressor for a few minutes after being switched off, so that pressures inside the system can equalise. If you switched it off and straight back on, the indoor fan may run while nothing else happens. Wait five minutes before concluding anything. Doing this repeatedly is also hard on the compressor, so let it settle rather than clicking it on and off.
- Protection cut-out on low or unstable voltage. Many units and most stabilisers will refuse to run at all when the supply voltage is outside a safe band. On a Delhi afternoon in peak season, that band is genuinely crossed in some areas. The give-away is that the unit is dead at three in the afternoon and starts normally at eleven at night. That is protection working, not a failure.
A third, simpler one worth checking on the remote: a timer set to switch the unit off, or a sleep schedule someone else in the house configured. If the AC dies at the same time every night, look at the timer before you look at the machine.
The Delhi supply problems behind most dead ACs
Three local conditions produce this complaint again and again across Delhi NCR.
- Afternoon voltage sag. When every AC in the colony is drawing at once, the voltage at your socket falls. Protection circuits cut in, stabilisers drop their output, and the AC goes dead. Nothing is broken. If your unit only refuses at peak hours, get the supply voltage checked before anyone opens the machine.
- Stabilisers that quietly die. A stabiliser lives on a shelf for years, takes every surge the supply throws at it, and eventually fails — often by simply not passing power through. Because it sits between the socket and the AC, its failure looks exactly like a dead AC. Borrowing a known-good stabiliser, or checking whether the unit runs without it where the manufacturer permits that, settles it quickly.
- Sockets and plug tops cooked by an AC load. An AC plugged into an ordinary socket on old wiring warms the contacts over years until the connection fails. This is common in older Delhi flats where the AC was added to whatever socket was nearest. The symptom is intermittent at first — it works, then it does not — and it is a genuine fire risk, so it belongs with an electrician rather than with patience.
Our home electrical safety tips cover the basics of what to do while you are waiting for someone.
If the power is fine, what is likely inside the unit?
Now the fault is genuinely in the machine. You cannot check these yourself and should not try, but knowing what they are makes the conversation with the technician a much better one.
- Nothing at all, not even a light or a beep. Power is not reaching or passing through the indoor board. Common causes are a blown internal fuse, a failed transformer or supply section on the board, or damaged wiring between the indoor and outdoor units. A fuse is a small part; the board is not, so ask which is being replaced.
- Indoor unit lights up and the fan runs, but the outdoor unit never starts. The control side is alive. Suspect the capacitor, the contactor, the outdoor fan motor, or a compressor that is not starting. This is a very common pattern and it is usually not the most expensive of those.
- It starts, runs for a few seconds, and shuts down. Something is tripping a protection — overload, high pressure, or a sensor. Note exactly how many seconds, because it helps.
- A display code or a blinking light pattern. Write it down or photograph it before anyone arrives. On an inverter unit it is the single most useful piece of information you can hand over, and it makes it much harder to be sold a part that was not diagnosed.
Do not open the electrical covers, do not test anything inside the unit, and do not work on the wiring. Capacitors can hold a charge after the power is off, and there is nothing inside an AC that a homeowner needs to touch.
Calling someone: what to say and what to ask
A dead AC is one of the easiest faults to be overcharged on, because the customer has no information and the failure sounds serious. Arrive with information instead.
- Say exactly what is dead. “No light on the indoor unit and no beep from the manual button, the socket tests fine with a lamp, the MCB is on” is a diagnosis handed over in one sentence.
- Say whether it is time-of-day dependent. Dead in the afternoon and fine at night points at supply, and saying so up front can save an unnecessary parts visit.
- Ask for the supply voltage to be measured at the socket. It takes a minute with a meter and it settles the supply question with a number instead of an opinion.
- Ask what specifically failed and how it was tested. Fuse, capacitor, contactor, sensor or board are different answers with very different costs. If the answer is the board, ask what ruled out the cheaper parts. Our guide on inverter AC PCB repair explains what drives that job.
- Do not accept a gas refill for a dead unit. Refrigerant level has nothing to do with an AC that will not power up, and offering one for this complaint is a sign to get a second opinion.
- Keep the old part and pay after. Ask for anything replaced to be handed back, and pay the technician directly once the unit runs.
If the fault turns out to be the circuit rather than the AC, that is an electrician’s job — our guide on an MCB that keeps tripping in Delhi covers the circuit side.
Need an AC & Appliance Repair professional?
Get free quotes from independent, local professionals near you. XpertWorker never charges you — you pay the professional directly.
Get free quotes →Frequently asked questions
Why is my AC not turning on at all?
My AC has power but does not respond to the remote. Is it dead?
Can a stabiliser stop my AC from starting?
Why does my AC only work at night and not in the afternoon?
My AC indoor fan runs but the outdoor unit does not start. What is wrong?
Does a dead AC mean the PCB has failed?
How we put this guide together
This guide is compiled from common Delhi NCR service patterns and reviewed by the XpertWorker team. XpertWorker connects you with independent, local professionals — we never charge you a paisa, and each professional sets their own price and quotes you free.