A 2021 BMW 3 Series came into us recently for an air conditioning regas. The customer had noticed the air con was not performing the way it should, and after connecting the car to our diagnostic equipment it was clear why. The system was running almost completely dry of refrigerant.
The System Contained Only 30 Grams of Refrigerant Against a Required 550 Grams
When we pulled the car in and connected our specialist service machine, the reading came back at just 30 grams of R1234yf refrigerant remaining in the system. The label under the bonnet on this BMW states clearly that the system requires 550 grams, with a tolerance of plus or minus 15 grams. That means the car was running at roughly five percent of what it should have contained. At that level, the air conditioning compressor is working against nothing. The cold air the customer expected was simply not there because there was not enough refrigerant present to transfer heat away from the cabin air. It is worth noting that this vehicle uses the newer R1234yf refrigerant rather than the older R134a type. The two are not interchangeable and require separate, dedicated service equipment. Using the wrong machine or the wrong gas on a system like this causes damage and can be a safety risk, as R1234yf behaves differently under pressure and temperature. We have the correct equipment for both types here at the garage.
Leaving a System This Low Puts the Compressor at Risk and Makes the Problem More Expensive to Fix
An air conditioning compressor relies on the refrigerant itself to carry lubricating oil around the system. When the refrigerant level drops as low as 30 grams, the oil circulation is severely reduced. Run the system long enough in that state and the compressor begins to wear prematurely, and in some cases seizes. A compressor replacement on a BMW 3 Series is a significantly bigger job than a regas. You are looking at a component that can cost several hundred pounds on its own before labour is even factored in. The moisture side of it matters too. When refrigerant leaks out slowly over time, air and moisture can work their way into the system. Moisture in an air conditioning circuit reacts with the refrigerant to form acids, which attack seals, valves, and internal components. That is why the vacuum phase of a regas is not just a formality. It is the step that removes moisture and old gas before anything new goes in.
The System Was Vacuumed Down Thoroughly and Recharged to the Full 550 Gram Specification
Before we put any new refrigerant into the system, the service machine held the circuit under vacuum for a sustained period. This draws out residual moisture and any remaining old gas, leaving the system clean and dry before the recharge begins. Once we were satisfied with the vacuum hold, the machine filled the system back up with fresh R1234yf refrigerant to the manufacturer specification of 550 grams. After the recharge was complete, we confirmed the system was performing correctly and blowing cold as it should. The whole job was carried out using equipment designed specifically for R1234yf, which is the only correct way to service this type of system.
If Your Air Con Is Blowing Warm, Do Not Leave It Until the End of Summer
Air conditioning systems lose refrigerant gradually over time, even on well-maintained vehicles. Most manufacturers recommend a regas every two to three years as a routine service item, though many customers only notice a problem when the warm weather arrives and the air con stops keeping up. If you are based in or around Walsall and your air conditioning is blowing warm, taking longer than usual to cool the cabin, or has not been serviced in a few years, it is worth getting it checked before the problem develops further. The cost of a regas is a fraction of what a compressor replacement would set you back. At Platinum Vehicle Services we carry out air conditioning servicing on a wide range of vehicles using the correct equipment for both R134a and the newer R1234yf systems, so whatever you drive, we can handle it. Book in with us at platinumvehicleservices.co.uk
