The Heavy Duty A/C System Experts

Revised September, 2023

Understanding the 2 Types of A/C Systems

It’s Hot Outside, We’re Here to Help

A/C System with Expansion Valve

Expansion Valve systems offer adjustable refrigerant flow to meet the varying demands of complex A/C systems. This provides consistent cool air temperatures even in stressful environments. The expansion valve plays a crucial role in balancing the refrigerant flow, ensuring sufficient cooling without freezing the evaporator. Additionally, expansion valve systems incorporate a receiver drier to filter contaminants and residual moisture in the refrigerant or lubricant.

Orifice Tube A/C System

In an Orifice Tube system, the orifice tube meters the amount of refrigerant entering the evaporator. However, unlike the Expansion Valve system, it cannot vary the refrigerant flow based on system demands.

The Orifice Tube system utilizes an accumulator, located before the compressor, to filter out contaminants and residual moisture. In this system, the refrigerant remains in a semi-liquid state. As such, the accumulator helps it descend to the bottom and vaporize before reaching the compressor. A properly functioning accumulator is crucial as compressors cannot handle liquid refrigerant.

Ensuring the comfort and safety of your truck's cab is crucial for truck drivers and fleet owners. The A/C system actively provides a cool and comfortable environment during long hours on the road. Understanding the different types of A/C systems and their components is essential to maintaining optimal performance and preventing costly repairs. In this article, we will explore the two main types of heavy-duty A/C systems: Expansion Valve and Orifice Tube.

Standard Components of A/C Systems

Expansion Valve

The Expansion Valve is responsible for metering the refrigerant flow. However, due to its small valve openings, it is prone to failure from particles. Replacing the expansion valve is essential whenever opening or servicing the A/C system.

Orifice Tube

Orifice Tube (CCOT) : The fixed orifice tube meters refrigerant in an accumulator system. It is prone to failure due to clogging particles in its small openings. Just like the expansion valve, you must replace the orifice tube whenever you open or service the A/C system.

Compressor

The Compressor acts as the heart of the A/C system, pumping refrigerant and oil throughout the system. Typical compressor failures include head pressure issues, improper refrigerant levels, and inadequate lubrication.

Condenser

The Condenser’s primary function is to remove heat by dissipating it while compressing the refrigerant back into a liquid state. Common condenser failures include build up of bugs or debris, fin damage, leaks from vibration or fittings, and internal restrictions. These issues may lead to clogged A/C drain lines, restricting the flow. You must replace parallel flow condensers and cannot flush them.

Receiver Drier

The Receiver Drier is positioned just past or as part of the condenser outlet. It actively filters liquid refrigerant and removes moisture from the A/C system. Moisture can cause acidic refrigerant conditions, leading to internal damage. Just like the expansion valve, you must replace the receiver drier whenever you open or service the A/C system.

Accumulator

Accumulator (CCOT) : The accumulator collects liquid refrigerant from the evaporator and filters it while removing moisture from the A/C system. You must replace the accumulator whenever you open or service the A/C system.

Rely on Expertise for Optimal Performance

Gain optimal performance and longevity of your heavy-duty truck's A/C system. You can achieve this by understanding the two main types of A/C systems: Expansion Valve and Orifice Tube. Properly maintaining and replacing components, including thorough flushing and inspecting for debris, contaminants, moisture, and air. In doing so, you can prevent system inefficiencies and failures.

Trust the expertise of FleetPride's Heavy Duty A/C System Experts. FleetPride provides you with the cleanest air for your truck's cab, ensuring maximum comfort and safety on the road.

* The forgoing is provided for informational purposes only. Please consult your local FleetPride Heavy Duty Experts to verify the suitability of a part for the intended application.