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Common AC Parts and the Repairs They Need

What would we ever do without an air conditioning unit in our homes? Truly, it is thanks to the AC unit that we are able to enjoy the hot summer days and get cozy during the crisp winter season. The AC unit is a complex system that has many parts working together to provide cool air during hot weather. Understanding the different parts of an air conditioning unit can help homeowners and technicians diagnose problems and ensure proper system maintenance . As the top air conditioner repair techs in Marysville, we will discuss the most common parts of an air conditioning unit to help you recognize potential repairs.


The compressor is perhaps the most important part of the AC; without it, the unit will not function. The compressor to an air conditioning unit is like the transmission to a car. The key function of compression is to pump refrigerant throughout the system to remove heat from the air.  It essentially compresses the refrigerant, causing it to heat up and become a high-pressure gas. This gas then flows to the condenser. 

Below are some telling signs that your compressor needs repair: 

  • Warm air coming from the vents
  • Strange noise
  • Vibration in the AC unit
  • High energy bills 

If you notice any of these signs, do not hesitate to contact an air conditioning repair tech in Marysville. 


The condenser is also known as the outdoor unit of the air conditioning unit. The condenser is responsible for converting high-pressure gas back into a liquid form. This liquid will then flow through the condenser, releasing the heat into the surrounding air, which is blown away by a fan. The cooler liquid refrigerant then flows to the evaporator. 

Though most condensers are built to last, you may need to contact a repair tech if you observe the following signs of repair:

  • Reduced cooling performance
  • Tripped circuit breaker
  • Leaking refrigerant 
  • High energy bills


The evaporator is the indoor unit of the air conditioning unit. This is where the liquid refrigerant is converted back into a gas. As the refrigerant evaporates, it absorbs heat from the surrounding air. That air is cooled, then blown back into the room by a fan, and distributed throughout the home via the ductwork. This process is repeated over and over again during the work of the air conditioning system. 

Evaporators develop malfunctions from time to time, and if you notice the following signs of repair, be sure to call an air conditioning tech in Marysville:

  • Decreased cooling function 
  • Ice buildup 
  • Foul odors
  • Build up of moisture

Expansion Valve 

The role of the expansion valve is to regulate the flow of refrigerant fluid from the high-pressure side of the system to the low-pressure side. It performs this function by creating a pressure drop in the refrigerant fluid, which causes it to evaporate and absorb heat from the air.

If the expansion valve is not functioning properly, it can cause a variety of issues with your air conditioning system. Here are some common signs that your expansion valve may need repair:

  • Poor cooling performance
  • Buildup of frost
  • Odd sounds coming from the AC
  • High pressure or low pressure in the AC system
  • Poor energy efficiency

Refrigerant Fluid

Refrigerant fluid is a chemical substance that is used to transfer heat from the air inside your home to the air outside. There are many different types of refrigerants, but the most common is R-410A. It is a more environmentally friendly refrigerant that is used in newer air conditioning units. Sometimes an air conditioning service tech in Marysville may need to come in to perform the following services: 

  • Recharging the refrigerant
  • Fixing refrigerant leaks
  • Flushing the refrigerant lines
  • Changing the refrigerant

Top Rated Air Conditioning Service in Marysville

Are you in need of air conditioning repair in your home? Whether you require attention to one of the aforementioned AC parts or to a whole other component, CM Heating is just a phone call away to restore your AC back to order.


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