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Poor cooling or heating

Poor cooling or heating — Air conditioner not performing effectively

MHI · Air Conditioning

What does Poor cooling or heating mean?

The air conditioner is not providing sufficient cooling or heating to the room. This could be due to various factors affecting its performance or environment.

Common Causes

  • Doors or windows left open.
  • Too many people or a heat source in the room.
  • Clogged air filter.
  • Thermostat set at an unsuitable temperature.
  • Direct sunlight entering the room.

Repair Steps & Checklist

Click steps to track your progress.

  1. 1

    Check if all doors and windows in the room are closed.

  2. 2

    Ensure the air filter is clean and not clogged. Clean it if necessary.

  3. 3

    Adjust the thermostat to a suitable temperature setting.

  4. 4

    Block direct sunlight entering the room if it's affecting temperature.

  5. 5

    If the problem persists after these checks, switch off the power and contact your dealer.

Browse all codes in this manual (124)
Verified technical data. Last updated: April 2026

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Source: MHI Air Conditioning
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