Diagnostic Equipment

State-of-the-art Diagnostic Equipment

At CMS AutoAir we identify the refrigerant gas in your vehicle’s air conditioning system as to its purity for the correct system operation, usually 134a. The refrigerant analyser Identifies illegal replacements & blends including propane & butane, While quickly & automatically determining if the purity of R134a refrigerant is at industry acceptable levels. When purity levels drop below 98% this has an effect on the cooling capacity & operation of the air conditioners components. Air in the system can lead to premature compressor failure & other costly parts. By knowing its Pure 134a in the system, your air conditioning system will operate as it was designed toby the manufacturer. Side effects of excess air in an A/C system can lead to false readings in electronic low charge indicators in some vehicles; rapid clutch cycling and potential clutch failures; and noisy compressor operation.

Mixed refrigerants can result in elevated system operating pressures, and this includes CFC-12 mixed with HFC-134a. A mixture of these two refrigerants will raise operating pressures to a point higher than either would ever reach by itself in a “normally” operating system.

How high the pressure goes is determined by the mixture ratio between the two refrigerants. The raising of system operating pressures above normal can result in poor A/C performance. With some reclaimed refrigerants it is also essential to know the makeup of that refrigerant, whether it contains contaminants like, Air, Nitrogen, Hydro-carbons etc, possibly from a previous regas.

The use of flammable refrigerants in an automotive air conditioning system is usually without the consent of the system manufacturer, which not only compromises the warranties but can also raise safety concerns to the vehicle occupants should a leak appear.

It is for this reason CMS AutoAir want to know what’s in your car? We don’t use flammable refrigerants in your car, only 134a the approved & manufacturers designed refrigerant is used in your car. A printed diagnostic makeup of the refrigerant in your system can be produced at the completion of the repair confirming the refrigerant’s identity so you can be confident in what’s in your air conditioning system and achieving the cooling performance it was designed for.

Diagnostic equipment by CMS Auto Air in Newcastle

Have you had your air conditioner…

Careful leak detection is a must.

Difficult to find and troublesome leaks that can’t be found with other repairers is what we specialise in. With our advanced leak detection methods using Nitrogen/Hydrogen leak detection, leaks in your air conditioner will become a thing of the past with CMS Auto Air. 


Dry nitrogen can also be used for leak tests. For leak tests, the air-conditioning system is filled with dry nitrogen. The pressurised system is then monitored for a period (e.g. 5–10 min) to see if the pressure remains constant. Leaks can be detected through a “hissing” noise or foaming detergent solution being sprayed over the A/C components identifying the visible leakage spot, forming foam at the point of the leak.


To accurately detect smaller hard to find leaks, the empty a/c system is filled with a forming gas mixture of 95% nitrogen & 5% hydrogen. The components are checked for leaks using a special electronic leak indicator. Due to the fact that hydrogen is lighter than air, the sensor needs to be moved slowly above the a/c components. Typically this will find internal evaporator leaks with a great deal more certainty than most other methods. After the end of the leak detection process, the forming gas can then be released safely into the ambient air. This leak detection method complies with Article 6, & 3 of the EU Directive 2006/40/EC.

Using a hydrogen mixture in determining leak location in automotive a/c systems allows for high sensitivity testing with an environmentally friendly gas.


The injection of a UV dye solution when re-gassing your cars air conditioner is another sound method of leak detection used by CMS Auto Air. Once the Ultraviolet dye is added into the system it will remain in the system for years

Why we choose the hydrogen leak detection system 5% Hydrogen/95% Nitrogen as a Tracer Gas