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What Happens If You Install a 1.5 Ton AC in a 300–350 Sq. Ft. Room?

Normally, a 1.5 Ton AC is considered suitable for a room size of 110–150 sq. ft. But many people make the mistake of installing the same AC in a much larger hall (300–350 sq. ft.) thinking it will still provide sufficient cooling. Let’s break down what really happens in such a scenario.

1. Cooling Performance

When you run a 1.5 Ton AC in a 300–350 sq. ft. room, the AC struggles to bring down the room temperature.
After 2 hours at 24°C, the room temperature may only drop to 26.5°C on average.
Even if you set the AC to 16°C, the room will hardly go below 26°C because the AC is simply under-capacity for such a large space.
This means you will not feel uniform cooling. The spot directly in front of the AC vent may feel cooler, but in the far corners, you may still feel warm and even sweaty.

In short: The AC will never achieve the set temperature in such a big room.

2. Electricity Consumption & Power Bill

Because the AC cannot reach the set temperature, it will continuously run at full load (~1400 watts).
In a 24-hour test at 24°C, the AC consumed around 25–28 units of electricity.
At 16°C setting, the consumption was almost the same, because the AC kept running at maximum power the whole time.
This means whether you set it at 24°C or 16°C, the bill will be very high since the AC is always operating at peak power.

Expect your monthly bill to shoot up significantly if you run it 24×7.

3. Warranty Risk (Hidden Point from the User Manual)

Here’s the most important point many people don’t know:
If you use an AC in a room much larger than its recommended size, the manufacturer warranty may become void. This is clearly mentioned in most AC user manuals.

So, by installing a 1.5 Ton AC in a 350 sq. ft. hall, you’re not only wasting money on high bills but also risking your product warranty.

4. Best Possible Settings in an Oversized Room

If you still want to use the AC in a larger room:

Set the temperature to 27–30°C instead of 24°C or 16°C.
This way, the AC can at least achieve the set temperature and reduce power consumption slightly.
But realistically, for 300–350 sq. ft., you should have minimum 2 Tons AC capacity (or two 1.5 Ton units) for proper cooling.

Final Conclusion

1.5 Ton AC is not suitable for a 300–350 sq. ft. hall.
The cooling will be weak, uneven, and never reach the desired temperature.
Power bills will be extremely high since the AC runs at full load nonstop.
Warranty may be voided if used in a room larger than recommended.
Always use an AC Capacity Calculator to determine the correct tonnage for your room size before purchasing.

For your 300–350 sq. ft. room, the right choice would be at least a 2 Ton Inverter AC.

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