TL;DR: This AC maintenance checklist has 12 checks for the week you switch off your split AC for a Gurgaon or Delhi NCR winter. It takes about an hour per unit. While the AC still runs, record any faults. Then wash the filters, run fan mode for 1–2 hours to dry the coil, switch off the MCB, take out the remote batteries and fit a breathable outdoor cover. Through the winter, run fan mode for 15–20 minutes every 2–3 weeks.
Key takeaways
- While the AC still runs, record weak cooling, error codes, drips and noises. Book a diagnosis in November instead of waiting for the April rush.
- After washing the filters, run fan mode for at least 1–2 hours so a damp coil and drain tray don't sit sealed for four months.
- Switch off the AC's MCB or dedicated switch for the season and take the batteries out of the remote.
- Cover the outdoor unit with a breathable fabric cover, leaving roughly 4–6 inches open at the bottom of each side. Never use sealed plastic, which traps fog moisture against the metal.
- Treat oil stains under the outdoor unit as a possible refrigerant leak. Book a pressure and leak check, not a blind gas refill.
Run this AC maintenance checklist the week you stop using your split AC, usually early or mid November in Gurgaon. It takes about an hour per unit, and when you're done, any existing fault has been caught while there's time to fix it. The unit also won't sit damp, powered on or exposed to NCR smog and pigeons for four months. Many summer AC breakdowns are set up in November: a damp coil, a powered unit and an uncovered condenser left alone until April. The 12 items below are in execution order across three phases. Each one names the failure it prevents and what skipping it costs.
Phase 1: Before you switch off (while the AC still runs)
Do these four checks on a warm afternoon while the AC still works. A fault you record now can be diagnosed and fixed in the off-season, not in the April rush when technicians are busiest. The graphic below shows the full 12-point sequence. Phase 1 is the step most winter guides skip.
☐ 1. Set cool mode to the lowest temperature (16–18°C), run it for 15 minutes and confirm the vent air feels distinctly cold.
Prevents: no cooling in summer. The lowest setting keeps the compressor running even when a November room is already near 24–26°C, so the test isn't cut short. The air should feel distinctly cold, not just cool or close to room temperature. If it doesn't, the cause is usually airflow, low refrigerant or a weak compressor. Skip it and you find out on the first hot day of April. For the full method, use the 5-minute self-check before booking a repair.
☐ 2. Photograph any error code on the display, and note any rattling, grinding or clicking from the outdoor unit.
Prevents: compressor and fan noise turning into a seized part. A loose mount or a worn fan bearing doesn't get better after months of idling and rust. Skip it and the technician has to diagnose from scratch in summer. A photographed code and a one-line description of the noise usually mean the right part arrives on the first visit.
☐ 3. Check the wall below the indoor unit and along the pipe run for drip marks or damp patches.
Prevents: water leakage. A slow drip usually means a partly blocked drain or a poor slope. Skip it and next season's drip becomes a stained wall or swollen furniture. See why an AC leaks water inside for the causes.
☐ 4. Look for oily patches on the outdoor unit, at the copper pipe joints and on the floor or ledge beneath it.
Prevents: a slow refrigerant leak becoming a compressor problem. A Techno Power Aircons checklist (January 2026) puts it plainly: "Oil often means a refrigerant leak, which requires a technician." Refrigerant doesn't get used up. If it's low, it has leaked somewhere. Skip it and you pay for a gas top-up in summer that leaks out again.
Decision rule: if any of checks 1–4 shows a problem, book a diagnosis this month and finish Phase 2 after the repair. If all four are clean, go straight to shutdown day.
Phase 2: Shutdown day (about 60–90 minutes)
Shutdown day dries the AC out, cuts its power and protects the outdoor unit for a four-month idle period. Most of the time goes on the dry-out run in item 6, and you can do the outdoor items while it runs.
Indoor unit: items 5–6
☐ 5. Switch the AC off, remove the indoor filters, wash them and let them dry fully in shade before refitting.
Prevents: weak cooling and a musty smell at the first switch-on. A clogged filter left in for months traps damp dust against the coil. Here's how to clean your AC filter at home. Skip it and the first April run blows stale, dusty air across the room.
☐ 6. Refit the dry filters and run fan mode, with the compressor off, for at least 1–2 hours on a dry day.
Prevents: water leakage, smell and corrosion. Months of cooling leave the coil and drain tray wet. Daikin's split-AC operation manual tells owners to "operate the 'FAN only' for several hours on a fine day to dry out the inside" before long non-use. ABP Live (25 October 2026) calls switching off and covering a damp AC straight away a common and costly mistake. Skip it and the drain tray grows slime that blocks the outlet next summer.
Outdoor unit and power: items 7–10
☐ 7. Clear the outdoor drain outlet and keep about 60 cm clear in front of and beside the outdoor unit.
Prevents: no cooling and corrosion. Techno Power Aircons gives 60 cm as a working clearance. On a wall bracket the back faces the wall, so measure the front and sides, and follow your unit's installation manual where it differs. Remove leaves, plastic bags, plants and stored boxes, and make sure the unit isn't standing in water. Wipe only the surfaces you can reach. Never use a pressure washer, and don't bend the fins. Dust and water trapped around the base speed up rust on the pan and fan mounts.
☐ 8. Inspect the copper-pipe foam insulation along its whole visible run, and check that the wall hole where the pipes enter is sealed.
Prevents: refrigerant leaks and wire damage. Voltas (August 2025) warns that damaged insulation "can reduce cooling efficiency and lead to leaks in summer." ABP Live advises sealing wall gaps to keep rodents out. Photograph any cracked, missing or chewed section for a technician. Skip it and exposed pipes and gaps give rats an easy path to the wiring.
☐ 9. Switch off the AC's dedicated switch or MCB for the season, and take the batteries out of the remote.
Prevents: PCB and electrical faults. Voltas advises disconnecting an AC you won't use for several months. Daikin's manual says: "When the system is not used for a long time, take the batteries out." Batteries left in for four or five months can leak and corrode the remote's contacts. Switch off at the breaker only. Don't open panels or touch wiring.
☐ 10. Fit a breathable fabric cover on the outdoor unit, leaving roughly 4–6 inches (10–15 cm) open at the bottom of each side, and leave the indoor unit uncovered.
Prevents: no cooling, corrosion and PCB damage. Moneycontrol (16 October 2026) explains that NCR smog settles on the condenser fins and, "when this layer mixes with fog moisture, it hardens and becomes difficult to clean." It also notes that pigeon droppings are acidic. Voltas advises a breathable cover so condensation isn't trapped inside, and ABP Live (November 2025) warns against polythene or plastic covers and says to keep the cover loose. The open gap at the bottom lets air move and moisture escape. The indoor unit needs only a dry wipe.
Phase 3: Through the winter (10 minutes a month)
Two short routines keep an idle AC healthy until March: a brief fan run and a look under the cover. Together they take about 10 minutes, and they catch damage while it's still cheap to fix.
☐ 11. Every 2–3 weeks, switch the MCB on, run fan mode for 15–20 minutes, then switch the MCB off again.
Prevents: water leakage and noisy start-ups. Voltas recommends exactly this interval, saying it "keeps internal components lubricated and prevents moisture accumulation." Take off any indoor cover first. Skip it and moisture builds up in a sealed-up indoor unit for four months, and the first run brings smell and drips.
☐ 12. Once a month, and after any storm or dust spell, lift the edge of the outdoor cover and check for nests, droppings, chewed insulation or standing water.
Prevents: PCB and wiring faults. A Moneycontrol follow-up (21 October 2026) notes that water can reach the outdoor unit's wiring and circuit board, "a problem most users discover only when the AC fails to start in March or April." If your unit sits on a high-floor bracket, a rooftop or a builder-floor ledge, also check after high-wind days. Wind loosens covers and wears pipe insulation faster at height.
What each item prevents: the five summer failures
Each of the five failures people find at the first switch-on in spring maps to specific checks on this list. Use the table to see what you're risking if you skip a check. Then use the linked guides if a symptom has already appeared.
Summer failure | Checks that prevent it | What usually goes wrong if skipped |
|---|---|---|
No or weak cooling | 1, 5, 7, 10 | Clogged filter, smog-crusted fins or an undetected fault found in April |
Water leakage indoors | 3, 6, 11 | Damp drain tray grows slime and blocks the outlet |
Compressor or fan noise | 2, 7, 12 | Loose mounts or nests in the fan, worsened by rust |
Refrigerant leak | 4, 8 | Slow leak at joints or exposed pipe, then a repeat gas top-up |
PCB or electrical fault | 9, 12 | Moisture, droppings or rodents reach live wiring |
If the breaker trips the moment you switch on in spring, stop resetting it and read what to check when an AC trips the circuit breaker. That's an electrical fault, not a maintenance task.
Where DIY stops: book a technician
Stop and book a professional if any check turns up a sign of a refrigerant, electrical or mechanical fault. Your part of the checklist ends at looking, cleaning and switching off.
- Oil stains at joints or under the outdoor unit
- A hissing sound near the pipes or the outdoor unit
- Chewed wires or insulation
- A burning smell, or marks on the plug or switch
- The MCB tripping when the AC starts
- Noise that is still there after clearing debris
- Cooling that stays weak with a clean filter
A gas refill should only follow a pressure check and leak inspection. Refrigerant runs in a sealed circuit, so low gas means there's a leak to find and fix first. A technician who offers to "top up" without testing is a red flag.
If your AC is still under the manufacturer's warranty, take it to the brand's authorised service centre first. If it's old and the quote involves the compressor, weigh it against our guide to whether to repair or replace an old AC. For out-of-warranty units in Gurgaon, Eazzy's technicians inspect and diagnose before naming a cost. You approve the quote before any work starts, jobs are verified by OTP in the app, and selected services carry a service warranty under the applicable warranty terms.
Non-negotiables and a version to copy
If you only do four things this November, do these: the 1–2 hour fan-mode dry-out (item 6), MCB off for the season (item 9), a breathable cover rather than plastic on the outdoor unit (item 10), and a booked leak check if you find oil stains (item 4). These four prevent the most expensive failures: mould in the drain tray, electrical damage and a refrigerant leak that ends up harming the compressor.
Copy this list into WhatsApp or your notes app and run it once for each AC:
AC WINTER SHUTDOWN CHECKLIST
Phase 1 – while it still runs
- Cool mode at lowest setting (16–18°C), 15 min: vent air distinctly cold?
- Photograph error codes; note outdoor rattles, grinding or clicks
- Check wall below indoor unit for drip marks
- Check outdoor unit, pipe joints and floor for oil stains
(Any problem in 1–4: book a diagnosis now)
Phase 2 – shutdown day
- Wash filters, dry fully in shade, refit
- Fan mode 1–2 hours minimum on a dry day
- Clear drain outlet; keep about 60 cm clear in front of and beside outdoor unit
- Inspect pipe insulation; check wall hole is sealed
- MCB/dedicated switch OFF; remote batteries out
- Breathable cover on outdoor unit, 4–6 inches open at bottom of each side (no plastic); indoor unit uncovered
Phase 3 – through winter
- Every 2–3 weeks: MCB on, fan mode 15–20 min, MCB off
- Monthly and after storms: check under cover for nests, droppings, chewed wires, water
Conclusion
Block out an hour this weekend, before the first properly cold night, and start with Phase 1 while the AC can still run in cool mode. If all four baseline checks come back clean, finish shutdown day the same afternoon and set a phone reminder for the fan run every 2–3 weeks. If any check shows a problem, book the diagnosis now. In November a technician can take the time to find the cause. In April, demand peaks and slots are harder to get.
Frequently asked questions
Should I cover my AC outdoor unit in winter?
Yes in Delhi NCR, but use a breathable fabric cover and leave roughly 4–6 inches open at the bottom of each side. Moneycontrol (October 2026) reports that winter smog settles on the condenser fins and hardens once it mixes with fog moisture, and that pigeons and rodents use idle units. Voltas advises a breathable cover so condensation isn't trapped inside, and ABP Live (November 2025) warns against polythene or plastic covers and says to keep the cover loose.
Should I cover the indoor AC unit in winter?
There's usually no need. The indoor unit is protected inside the home. Wipe the body and grille with a dry cloth after the dry-out run and leave it uncovered. If you want to keep dust off, use a loose, breathable cover that doesn't block the air inlet or outlet, and take it off before the monthly fan-mode run.
Should I switch off my AC at the main switch or MCB for winter?
Yes. For a four-month idle period, switch off the AC's dedicated switch or MCB after the dry-out run. Voltas recommends disconnecting an AC you won't use for several months. Use only the switch or breaker. Don't open panels or disconnect any wiring yourself. Switch the MCB back on only for the short fan-mode runs during winter.
How do I dry my AC before switching it off for winter?
Wash the filters, let them dry fully in shade and refit them. Then run the AC in fan mode, with the compressor off, for at least 1–2 hours on a dry day. Daikin's operation manual tells owners to run 'FAN only' for several hours to dry out the inside before long non-use. A damp coil and drain tray left sealed grow mould and smell.
How often should I run my AC in winter?
Voltas recommends running the AC in fan mode for 15–20 minutes every 2–3 weeks during low-use months. This keeps internal components moving and stops moisture building up. Switch the MCB on for the run, take off any indoor cover, then switch the MCB off again afterwards. You don't need cooling mode in winter.
Should I get my AC serviced before winter or before summer?
Book the full service before summer, ideally in February or early March before demand peaks. The winter shutdown checklist doesn't replace that service. If your November baseline check finds weak cooling, a drip, an odd noise or oil stains, book a diagnosis now rather than waiting. Off-season visits are easier to schedule, and you start summer with a working unit.
