What temperature to set your AC to in India

Updated August 25, 2026 · Claude AC · 2 sources cited

Contents (8)

Where 24 °C comes from
What each degree actually costs
Why a lower setting does not cool faster
Humidity does half the work
The ceiling fan is not optional
Night settings, timers and the sleep function
Setting by climate, in one table
Frequently asked questions

Most Indian households treat the AC remote as a throttle: 45 °C outside, so set 16 °C and the room will cool faster. It will not. A thermostat sets a destination, not a speed — the compressor runs at the same capacity on its way to 16 °C as it does on its way to 24 °C, and the only thing the lower number changes is how long it keeps running after the room is already comfortable. That difference is the entire argument, and it is worth a visible fraction of a summer electricity bill.

Where 24 °C comes from

The number is not folklore. In 2020 the Bureau of Energy Efficiency, under the Ministry of Power, made 24 °C the mandatory default setting for star-rated room air conditioners sold in India: switch a new machine on, and that is where it starts. The reasoning was arithmetic at national scale — room air conditioning is one of the fastest-growing drivers of India’s summer peak demand, and a few degrees of collective restraint moves gigawatts.

The policy has since gone further. In June 2025 the Union power minister announced that the government had asked BEE to prepare a framework restricting the settable range on new air conditioners to roughly 20 °C to 28 °C, ending the 16 °C setting altogether. At the time of writing the framework has been announced rather than notified, so no date should be treated as fixed; what is settled is the direction of travel, and any machine bought today will still start at 24 °C.

What each degree actually costs

The physics is straightforward: the lower the setpoint, the larger the temperature difference the machine has to maintain against the outdoors, and the longer the compressor runs. Field and laboratory studies converge on a rough figure of 3 % to 6 % of cooling energy per degree Celsius — the exact value depends on the machine, the insulation and how hot it is outside. Applied to a typical setpoint ladder, that compounds quickly:

Setpoint	Indicative energy relative to 24 °C	What it feels like
18 °C	Roughly 25–35 % more	Cold; most people add a blanket, which is the tell
20 °C	Roughly 15–25 % more	Cool, comfortable for very few Indian households
22 °C	Roughly 6–12 % more	Comfortable in high humidity, generous elsewhere
24 °C	Baseline	The BEE default; comfortable for most people with fan support
26 °C	Roughly 6–12 % less	Comfortable in dry heat with a ceiling fan running
28 °C	Roughly 12–20 % less	Acceptable at night in dry climates; marginal in coastal humidity

The percentages are bands, not guarantees: consumption also depends on the ISEER of the machine, on how well the room holds cool air, and on whether the outdoor unit is baking in afternoon sun. But the ordering never changes, and on the bill it is real — the method for putting rupees on it is in our electricity bill guide.

Why a lower setting does not cool faster

A fixed-speed compressor has exactly one output: on. Set 16 °C or 24 °C and the machine removes heat at the same rate; the room reaches 24 °C at the same moment either way. The difference arrives afterwards — at 24 °C the compressor cuts out, while at 16 °C it keeps running toward a target it may never reach on a 44 °C afternoon.

An inverter machine behaves differently in the detail and identically in the conclusion. It modulates capacity, so it does run harder at first and then throttles down to hold the setpoint. But holding 16 °C in a Delhi May means running near full capacity indefinitely, which discards precisely the part-load efficiency you paid for. The mechanism is set out in our guide to inverter ACs; the practical instruction is the same for both technologies — pick the temperature you want to live at, and let the machine get there.

Humidity does half the work

Comfort is not temperature alone. At 60 % relative humidity a room at 26 °C feels warmer than the same room at 26 °C and 45 % humidity, because sweat evaporates more slowly. Air conditioners dehumidify as a by-product of cooling, and that is why the same setpoint feels adequate in Chennai and generous in Jaipur.

Two consequences follow. In coastal cities — Mumbai, Kochi, Kolkata, Chennai — a slightly lower setpoint, or a spell on dry mode, buys comfort that raising the fan speed cannot. In dry inland heat, the opposite: 26 °C with a ceiling fan is often more comfortable than 22 °C without one, and it is where an evaporative machine remains a serious alternative, which our comparison of air coolers versus AC settles city by city.

The ceiling fan is not optional

Air movement shifts perceived temperature by a couple of degrees for a few tens of watts, against an AC’s several hundred. A ceiling fan running alongside the AC lets the setpoint sit one to two degrees higher for the same comfort, and it breaks up the stratification that leaves cool air pooled at floor level. Of every trick on this page, it returns the most for the least effort.

Night settings, timers and the sleep function

Thermoregulation shifts during sleep, and a temperature that felt right at 11 p.m. is often unnecessarily cold by 3 a.m. — which is why households wake to switch the machine off, then wake again because the room has become intolerable. Two better options sit on almost every remote:

Sleep mode raises the setpoint automatically by a degree or two over the first hours, tracking the way comfort requirements ease overnight. It is the single most under-used button on an Indian remote.
The timer stops the machine after a set period, letting a well-shaded room coast until morning. In dry climates this works well; in coastal humidity it usually does not, because the moisture returns before the temperature does.

Switching the AC off entirely when leaving a room for ten minutes is counterproductive: the room reheats, and the machine pays the whole pull-down again. For absences of an hour or more, off is right; for short gaps, raising the setpoint is better.

Setting by climate, in one table

Situation	Sensible daytime setting	Sensible night setting
Dry inland heat — Jaipur, Nagpur, Ahmedabad	25–26 °C with a fan	26–28 °C, or sleep mode from 25 °C
Humid coast — Mumbai, Chennai, Kochi	24–25 °C, dry mode on muggy days	25–26 °C with sleep mode
Composite north — Delhi, Lucknow, Chandigarh	24–26 °C depending on the month	26 °C with sleep mode
Temperate — Bengaluru, Pune, Mysuru	26 °C, often fan alone will do	Timer for two hours, then off

Treat these as starting points to adjust downward only if genuinely uncomfortable — not as ceilings to be undercut on principle. And remember that the star label on the machine multiplies whatever you set: a 5-star inverter unit at 26 °C and a 3-star fixed-speed unit at 26 °C are not the same electricity bill, which is what the BEE star rating is measuring.

Frequently asked questions

Is 16 °C ever the right setting?

Only if you genuinely want a 16 °C room, which almost nobody does — the blanket that follows is the evidence. It does not accelerate cooling, it prevents the compressor from cycling off, and it is the setting the proposed 20–28 °C range is intended to remove from new machines.

Does 24 °C really save that much?

Against a habit of 18–20 °C, yes: in the order of a fifth to a third of cooling energy, depending on the machine and the climate. Against 26 °C it costs a little more. The honest framing is that every degree is worth roughly 3–6 %, and the total depends entirely on where you were starting from.

Should I use dry mode instead of cool mode?

In humid weather, and when the temperature itself is bearable, dry mode is often the more comfortable setting for less energy — it runs the compressor in short cycles at low airflow to wring out moisture. In dry heat it achieves little, because there is not much moisture to remove.

Does the AC use less power once the room is cold?

Yes. A fixed-speed compressor switches off entirely and only the fan continues; an inverter compressor throttles down to a fraction of its capacity. This is exactly the behaviour a too-low setpoint prevents, and exactly why the setpoint matters more than the number of hours the machine is switched on.

Where should the indoor unit be so the thermostat reads correctly?

High on a wall with a clear throw across the room, away from direct sunlight, curtains, cupboards and any heat source. A sensor reading air warmed by a west-facing window will hold the whole room colder than you asked for — a placement question decided on installation day, as our installation guide notes.