Two Types of Air Conditioning Systems In Your truck

Air conditioning systems is an essential component of every truck. It comes in handy when the cabin temperature is high and cools it down. Although it is used more often, most people do not understand how it functions and the types of air conditioning systems. After reading this guide, you can understand various air conditioning systems.

Most trucks use two main types of air conditioning systems. One uses the expansion valve system to reduce the refrigerant pressure, and the other uses the orifice tube. 

Expansion Valve System

The aftermarket AC systems use the efficient expansion valve system when it comes to regulating the refrigerant to the evaporator. It is situated at the firewall between the inlet, outlet tubes, liquid, and section lines.

Its disadvantage is that it might get clogged with debris, and its small moving parts may stick together or fail to function due to corrosion. 

Orifice Tube System

The orifice tube system is common in General Motors and Ford models. The orifice is at the inlet tube of the evaporator or sometimes the liquid line. The orifice tubes are about 3 inches long. It has small brass tubes with plastic surrounding it and a filter covering each end.

However, the orifice tube system has disadvantages, such as clogging from debris accumulation. The clogging is avoided by installing a larger pre-filter before the orifice tube. The high repair cost is another downside of the orifice tube system. 

How the Air Conditioning Systems Works

The air conditioning systems work through the transmission of AC gas between the liquid and gaseous states. The state transition is vital and aids in heat and humidity absorption, and provides cool and dry air in your cabin. Here is how each type of air conditioning system works.

There are four key stages for the expansion valve system to cool down your cabin. This is what happens in every stage.

Stage 1

The evaporator supplies the compressor with low-pressure refrigerant. Compression takes place, which results in a high-pressure refrigerant vapor that is carried to the condenser.

Stage 2

The condenser receives the hot, high-pressure refrigerant vapor. The heat exchanger has special tubes where the high-pressure refrigerant is forced down. The refrigerant vapor’s role is to absorb the heat within your cabin. The bottom of the refrigerant has a relatively lower temperature than the top. The lower temperature condenses the vapor released from the bottom of the condenser as a high-pressure liquid refrigerant.

Stage 3

A fan blows on the fins to cool the refrigerant vapor, which cools your truck even if it is not running.

Stage 4

The process occurs in the expansion valve where the high-pressure liquid refrigerant moves to the dryer as some go to the evaporator. The expansion valves moderate the temperature of the refrigerant vapor that leaves the evaporator. It also controls the quantity of liquid refrigerant moving into the evaporator. 


The air conditioning system plays the role of cooling the temperature within your cabin. There are two main types of AC. This guide has elaborated on how these two AC system work. Knowing the type and model of your truck will aid you in knowing the type of AC in your truck. 

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