One reason for air conditioner not cooling: Not enough Freon (also known as "snow seed" not enough)

This is a common situation, usually found in air conditioners that are three to four years old. The air conditioner doesn't stop cooling entirely, but the cooling effect is not as good. This is because older models use Freon as the refrigerant, which can evaporate over time. Additionally, there may be issues with incorrect installation leading to Freon leakage or inherent problems with the machine.

Reason #2 for Air Conditioner Not Cooling - Insufficient Voltage Supply

The voltage supply is unstable, often failing to reach the normal level, especially during peak electricity usage times when this issue tends to occur more frequently. Of course, this problem is clearly beyond the scope of a technically skilled air conditioning repairman. We must address the issue by ensuring a stable voltage supply.

What to do if the air conditioner doesn't cool: Maintain a normal power voltage or choose a variable-speed air conditioner. Why a variable-speed air conditioner can solve the voltage issue is answered in the article "What Are the Benefits of Variable-Speed Air Conditioners - A Comprehensive List of Benefits."

Three Reasons Why Air Conditioners Don't Cool - Insufficient Power

This is also one of the common reasons for no cooling, but the causes for this non-cooling can be various, such as: a low-power air conditioner in a large room, or in some cases, even though the air conditioner's power seems to match the room size, the room may not be well-sealed (e.g., doors and windows are wide open), or there may be heat sources inside the room (e.g., many computers can generate heat), of course, west-facing glass in a greenhouse can also be a heat source, etc.