1. Check the refrigerant

When central air conditioning fails to cool, it's usually due to a lack of refrigerant or because the unit hasn't been cleaned for a long time, leading to reduced heat dissipation efficiency in the cooling fins. At this point, we should first check if the refrigerant is low due to long usage or due to leaks. For units that haven't been cleaned in a long time, a thorough cleaning is necessary to ensure proper heat dissipation.

2. Indoor unit dripping

When a central air conditioner's indoor unit is leaking water, it's usually due to incorrect installation, not being level, or poor drainage from the air conditioner's drain pipe causing water leakage from the indoor unit. A clogged drain pipe is also a common reason for the indoor unit to leak. When encountering water leakage from the air conditioner's indoor unit, we can first inspect these aspects.

3. Excessive noise

During the operation of central air conditioning, if the noise is excessive, check if the outdoor unit's fan blades are deformed or if there is too much dust accumulation, which can cause loud noise during operation, or if the fins are blocked. An incorrectly placed compressor and excessive workload are also common reasons for loud noise during air conditioning operation. We can address the issue of loud noise in the same way by focusing on these aspects.