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Air conditioner does not work at all

Air conditioner does not work at all — Unit unresponsive

MHI · Air Conditioning

What does Air conditioner does not work at all mean?

The air conditioner is completely unresponsive and does not turn on. This can be caused by a lack of power supply or incorrect timer settings.

Common Causes

  • Power failure or a blown fuse/tripped circuit breaker.
  • Main power switch for the unit is turned off.
  • Timer set in the 'ON' position, which delays startup.

Repair Steps & Checklist

Click steps to track your progress.

  1. 1

    Check for a power failure in your home or a blown fuse/tripped circuit breaker.

  2. 2

    Ensure the main power switch for the air conditioner is turned on.

  3. 3

    Verify if the timer has been set to the 'ON' position, which delays startup.

  4. 4

    If the unit still does not operate, 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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