[Car Knowledge] Car air conditioning is not cooling and has a strange smell? This article will show you the reasons behind it and how to repair and maintain it.

I don't know if you have ever had the experience of having a strange smell. There will be a smell of shit coming out when you turn on the air conditioner. The editor can say that he has suffered from this himself. The following is a summary of the causes and solutions for the air conditioner not cooling well and having odor. I hope it can help everyone!

1. Cause Analysis

1. Common causes of insufficient cooling of air conditioner

• Insufficient or leaking refrigerant
  Insufficient refrigerant and the air conditioning is not cool enough.
• Air conditioner compressor is damaged or belt is loose
  The compressor cannot work and the air conditioner only blows air but does not cool.
• Condenser or evaporator plugged
  There is dust, insects and debris on the outside of the condenser; there is dust and mold inside the evaporator, which affects heat exchange.
• Fan failure
  The condenser or indoor fan speed is low and the heat dissipation is poor.
• Temperature control system or computer sensor failure
  The sensor readings are wrong, causing the refrigeration system to work abnormally.
• The pipe is damp or blocked
  Water or impurities have entered the system, causing the air conditioning to not cool.

2. Common causes of odor

• Evaporator/air conditioning duct is moldy and dusty
  Moisture accumulates, dust and mold multiply, and produce musty and smelly odors.
• Cabin Filter is dirty
  The filter is dusty and damp, creating a musty smell.
• Carpet and interior are damp
  Long-term moisture causes bacteria and mold to grow.
• Condensate drain hole blocked
  Condensed water accumulates near the evaporator, causing odor.

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2. Corresponding solutions

A. Solutions for insufficient cooling

1. Check and replenish refrigerant
   • Have a professional garage check for leaks and add appropriate refrigerant.
2. Check the air conditioner compressor and belt
   • Repair or replace damaged parts.
3. Clean the condenser and evaporator
   • Clean the heat sink with high pressure air or a water gun.
4. Check fan operation
   • Check fuses, wires, motors, and repair or replace them.
5. Check sensors and control systems
   • Computer diagnosis, repair or replace depending on the situation.
6. Cleaning air conditioning ducts
   • Remove internal water and impurities.

B. Solutions with odor

1. Replace air conditioner dust filter
   • It is recommended to replace it once a year, and in serious cases, it can be replaced every six months.
2. Clean the evaporator and air duct
   • Use spray disinfectant to clean and special cleaner to remove musty odors.
3. Keep your car dry
   • Open the car doors regularly for ventilation, and dry the carpets/mats if they are damp.
4. Unclog the condensate drain hole
   • If the drainage hole under the vehicle is blocked, it should be cleaned.
5. Use antibacterial deodorant for air conditioners
   • Spray regularly at the air inlet and evaporator.

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3. Schematic diagram of common components

4. Daily maintenance suggestions

• Completely clean the air conditioning system every 1-2 years.
• Replace air conditioner dust filters regularly.
• If the air conditioner does not cool for a long time, do not force it to stay on for a long time and check it as soon as possible.
• If you find odor, you can use antibacterial deodorants, but a thorough cleaning is required to cure it.