07843 936155 / 0800 1930626 info@subzerouk.co.uk


Our aim is to keep the air conditioning system of your vehicle going as well as it was originally designed to work.

We service all types of vehicles from the current standard vehicles, classic and sports cars from the British, European, Japanese, American market to the larger vehicles like Tractors, Plant Machinery and Commercial HGV/PSV vehicles.

We can save you time and trouble by coming to your home or business with our specially equipped service vans. We handle both older R12/RS24 refrigerant gas systems (pre-1992 approx) as well as all modern R134a and R1234yf refrigerant systems.

A variety of leak testing techniques are available at our disposal including high pressure testing using environmentally safe pure Nitrogen, Ultra Violet dye and an electronic refrigerant sniffer. We can apply these individually or if necessary collectively to ensure we find and cure any elusive leaks.

Over the years we have built up a network of specialist parts suppliers  that ensures we can locate the right part for your vehicle, usually within 72 hours.

For the older R12 systems it is now impossible, due to environmental legislation, to offer this gas type. Our solution is to offer a true ‘drop in’ replacement to R12 known as RS24. This refrigerant solves the problem and considerable expense of having to completely retrofit your system to work with R134a or R1234yf refrigerant.

We are fast becoming Kent’s leading R12 to RS24 mobile replacement specialist. We are based in New Romney and the Folkestone area but cover the whole of Kent and also the surrounding areas of the M25.

Classic Cars - Early CFC refrigerant (R12 to RS24 drop-in)

Classic Cars

Early CFC refrigerant (R12 to RS24 drop-in)

Prior to 1993 the percentage of vehicles fitted as standard with aircon was relatively small. Jaguar Rolls Royce, Bentley,ect all used the popular refrigerant of the time R12 often called by the name Freon.

Around 1993 however once the potential environmental problems of this refrigerant which was a CFC were recognised a change to the refrigerant R134a was made for all new cars but it was at that time still entirely legal to use R12 to recharge the systems of these earlier vehicles which needed R12.

From 2001 onwards CFC’s were banned altogether and these earlier systems needed either conversion to R134a or the use of one of the drop-in refrigerants which were able to mimic R12 but were free from CFC’s.

Immediately after January 2001 with R12 now illegal most owners opted for the simple drop-in replacement we offer rs-24 as the drop in gas.

Standard Cars - CFC refrigerant (R134a / R1234yf)

Standard Cars

CFC refrigerant (R134a / R1234yf)

These days, most new cars come with some form of air conditioning or climate control. These systems use a special gas to cool the air which in turn helps control the temperature within the vehicle. The system also dehumidifies and cleans the air.

To avoid costly repairs and complete system failure, we recommend that the system is serviced and recharged at least every 2 years.

Contact us at your convenience for a temperature vent test, pressure test, and visual inspection. Over a period of time, the system can lose gas or become contaminated. In addition, filters gradually become saturated which can cause the system to become inefficient or fail completely

Some modern cars (often Mercedes) create Fault Codes (DTCs) when the refrigerant charge is allowed to get far too low. This has the effect of preventing the operation of the AC system even where it has been completely recharged. For the use of our Electronic Diagnostics Equipment to correct these DTCs there will be a small addition to the recharge cost if done at the same time.

Air conditioning units should be regularly serviced in a similar manner to other vehicle parts.


The main benefits are:

Improved system efficiency

The removal of potentially harmful bacteria

Reducing screen de-misting times

Inhibiting the recirculation of dust and pollutant particles

We can normally source most replacement parts either OE or pattern within 24 working hours

Some modern cars (often Mercedes) create Fault Codes (DTCs) when the refrigerant charge is allowed to get far too low. This has the effect of preventing the operation of the AC system even where it has been completely recharged. For the use of our Electronic Diagnostics Equipment to correct these DTCs there will be a small addition to the recharge cost if done at the same time.

Agricultural - CFC refrigerant (R134a)


CFC refrigerant (R12 – RS24) (R134a)

Although air conditioning is now considered a standard in the automobile industry, in the agricultural industry air conditioning is still a luxury that often affects the comfort of equipment operators.

When we first think of air conditioning, we automatically just think of comfort. However, it also plays a role in safety because it helps people to not feel as tired and fatigued when driving vehicles or operating machinery.

All in all, the purpose of the air conditioner is to provide cool dry air by removing the moisture or humidity and the heat energy from the air inside the cab of vehicles, which happens through a heat transfer cycle.

The air conditioning system as a whole is a sealed system. It operates under its own environment. The refrigerants inside the system are part of this environment. There really isn’t any rocket science here. It is just a system sealed internally that is controlled by heat and pressures. In conclusion, air conditioning is an item that people usually expect, even in the agriculture industry. You can hardly handle sitting in a combine, loader or a tractor with all that glass surrounding the cab anymore.

Plant Machinery - CFC refrigerant (R134a)

Plant Machinery

CFC refrigerant (R134a)

We offer servicing for all types of Construction and Industrial mobile air-conditioning systems

Our customers can depend on our reliable, professional, and efficient maintenance and support services at a time that is convenient for your company’s needs, even if it’s outside of our normal working hours.

Our vehicles come fully equipped and most repair work can be undertaken on-site, including hose and pipe repairs thus optimising repair times. Specialist parts can be ordered for next day delivery.

Carrying out a regular maintenance service to your equipment can reduce potential breakdowns and repairs.

We ensure your air conditioning systems are kept in good working order by offering a maintenance plan that suits the individual customers’ needs.

Our maintenance plan is designed to ensure your air conditioning system is operating to its best efficiency.

Commercial HGV/PSV - CFC refrigerant (R134a)

Commercial HGV/PSV

CFC refrigerant (R134a)

For heavy trucks and PSV we provide an AC servicing for a number of different fleet company’s.

Mostly we would be asked to find a leaking component and then after repair to return and evacuate, recharge with refrigerant and test the system.

Sometimes it would be a simple task of degassing the AC system to allow the removal of the condenser in order to replace a water radiator and then to evacuate and recharge after the repair was finished.

We have also managed to source new components at competitive prices for their AC systems.

One minute……the more comfortable the driver feels the more accurate is his work likely to be. When he is hot and uncomfortable he is more likely to make expensive mistakes

R1234yf Air Conditioning Regas Service


Did you know?

The Mobile Air Conditioning Systems (MAC) Directive introduced far greater focus on protecting the environment from greater climate damaging air conditioning system refrigerants.

From the 1st January 2017, a new more environmentally friendly vehicle air conditioning system refrigerant gas (known as R1234yf) has become widely used (instead of R134a) on passenger cars and Light Goods Vehicles (LGVs) up to 3.5 Tonnes.

For example, if R134a gas was released into the atmosphere, it had a lifespan of 13 years in comparison to just 11 days for R1234yf refrigerant.

R134a refrigerant gas was the most commonly used refrigerant gas by vehicle manufacturers in recent times up to 2017. The MAC Directive only applies to new vehicles since the start of 2017, so all vehicles currently using R134a are still able to continue to use that refrigerant.

A number of vehicle manufacturers switched to R1234yf refrigerant gas before 2017, so now there are a mixture of vehicles on UK roads using either refrigerant gas.


How can Subzero help?


Subzero offers a full range of air conditioning re-gassing solutions. R12 – RS24 Drop-in , R134a , R1234yf at either our workshop in New Romney or via one of our mobile service vans. Vehicle manufacturers typically recommend drivers get their refrigerant gas levels checked in their vehicle at least every 2 years, to ensure maximum system operating efficiency.

Specific air conditioning equipment is required to complete an R1234yf regas service. SubZero has everything required to meet all your Re-gassing requirements.

Price Lists

Diagnostic Air Conditioning Systems

To be at the top of our field we have invested heavily in the latest Snap-on diagnostic equipment as most new vehicles air conditioning are computer controlled

Over the last couple of decades, vehicle manufacturers have pushed boundaries to improve occupant safety and comfort. They have given us many innovations to enhance our driving experience while making vehicles safer. One tool that has evolved over many years is air conditioning, which now forms part of a vehicle’s active safety system.

Many cars now have air conditioning at the very least, or even climate control; systems that contain high- and low-pressure sides, compressors, condensers, evaporators and refrigerant, along with many more components. Most comfort systems now have some form of diagnostic capabilities, be it codes only, codes and data, or actuators.

When automatic air conditioning is working correctly, all of the components listed as actuators will be commanded by the control module to perform a given task.
However, when a system is not working as it should do, that is where diagnosing automatic air conditioning is a difficult task.

Using a diagnostic tool to actuate many of the components fitted in the system – like the blend motors, blower, hot and cold taps and other parts – is a must.
These components are usually in very hard-to-reach places at the rear of the dashboard, making access incredibly difficult.

We use the latest snap on diagnostic tools help us to carry out these tests

That said, before we rush in with the diagnostic tools, it is important to make sure that the basics have been checked first – such as ensuring that the mechanical system is good, visually inspecting the system, checking the correct amount of refrigerant and PAG oil, referring to technical data and using the air conditioning service station

Anti-bacterial & Odour Removal Treatment

We have invested In the latest anti-bacterial ozone cleaning machine from Snap-on. Over time the air con begins to generate unusual smells which are accustomed to. We can help clear that odour, leaving your car’s ventilation smelling as good as new.

Ozone Shock Treatment

Does your vehicle’s interior smell of old cigarette smoke, bad pet odours, vomit, mould, damp or any other nasty smell? Ozone shock treatment is the most effective chemical-free broad based sanitising method available to completely rid any nasty smelling odours & viruses, leaving your whole vehicle smelling clean and fresh.

Ever wondered how does your vehicle Air Conditioning actually work?

You need the 5 main pieces of equipment below to be working correctly


The Compressor transports the refrigerant at the required pressure through the air conditioning system. The refrigerant is a low-pressure gas as it enters the Compressor from the Evaporator. The Compressor increases the refrigerant pressure and also its temperature so it becomes a high-pressure gas which, in turn, helps the refrigerant condense more rapidly in the next component, which is the Condenser. The Compressor is mounted on the engine and is driven by a belt from the engine’s crankshaft pulley.


The Condenser works in the opposite way to the Evaporator. The refrigerant gives up its heat generated by the Compressor by passing cold air across its fins and tubes by ram air or by an extra fan. The end result of this change is that the refrigerant is now a high-pressure liquid and is forced out to the Receiver Drier through the liquid line.

Filter Drier

Depending on the type of air conditioning system fitted, this item can be called a Receiver Drier or an Accumulator. (The Accumulator is fitted on the low-pressure gas line of an air conditioning system between the Compressor and the Evaporator and is used in conjunction with an orifice tube). The Receiver Drier is fitted on the high-pressure liquid line of an air conditioning system between the Condenser and Expansion Device. The Receiver Drier has two parts to it, the receiver and, of course, the drier. The receiver section holds the right amount of refrigerant required by the system to ensure correct operation and to supply a steady flow of liquid refrigerant to the Expansion Device. The drier section is responsible for removing moisture from the air conditioning system by means of a bag of desiccant, which absorbs small quantities of moisture.

Expansion Device

The Expansion Device comes in many forms. It can be a brass internally or externally equalised valve, a block type valve or an orifice tube (the latter being part of an Accumulator type air conditioning system). Expansion Devices have an inlet and an outlet which separates the high side of the system from the low side. A small restriction in the valve allows only a small amount of refrigerant to pass through it into the Evaporator, the amount of refrigerant passing through the valve depends on the Evaporator temperature.


As soon as the liquid pressure drops, the refrigerant begins to boil (R134A refrigerant boils at approximately -26 degrees centigrade). As it continues to boil the Evaporator absorbs the heat passing over its tubes and fins and as a result, the air is cooled. Remember that heat is being removed from the warm air and cold air is not being created. The compressor, on its suction side, removes the low-pressure vapour from the Evaporator and the cycle starts all over again.

What can go wrong with your vehicle Air Conditioning?

Automotive air conditioning systems are designed to leak. Car engines vibrate, the pipework moves and the rubber ‘O’ rings expand and contract, all allowing leakage. Over a period of 12 months up to as much as 70% of the air conditioning refrigerant may have escaped from the system, leaving the air conditioning system to gradually perform poorly and eventually stop.


The Compressor is mounted on the engine and is driven by a belt from the engine’s crankshaft pulley. The most common reasons for failure are lack of oil, pulley bearing wear, electromagnetic coil burn-out, and lack of regular servicing.


The Condenser is usually located at the front of the vehicle behind the grill, it can become damaged by debris or corroded by materials from the road. It can also fail because of weak spots in its construction and lack of regular servicing.uid line.

Filter Drier

This is a very important part of the air conditioning system and should be changed at least every two years or when the system is repaired. The most common reasons for failure, is corrosion and desiccant deterioration, which leads to severe system failure.

Expansion Device

The most common reasons for failure are contamination, moisture, and lack of regular servicing.


The most common reasons for failure are corrosion, weak spots in construction and lack of regular servicing


Your air-conditioning system is alive! Whenever you switch on your air conditioning, bacteria, fungi and other micro-organisms can reach then the interior of the vehicle via the ventilation equipment. These pathogens cause unpleasant allergic reactions in many people: sneezing, coughing, streaming eyes, etc. On top of this, the micro-organisms cause a bad musty smell. Disinfection of your air conditioning system guarantees clean air and a great climate!

Over 20 years of experience in the industry

We pride ourselves on the excellent customer service that we provide for every project we undertake


Company Details



Contact Details

Phone: 0800 193 0626
Mobile: 07843 936155

Email: info@subzerouk.co.uk

Certified Marine Technician

Certified Webasto Dealer