Mitsubishi AC Pressure Test Carried Out in Walsall

A white Mitsubishi came into us recently for an air conditioning check. The customer had noticed the system was not cooling as well as it should, and wanted to know whether it needed a recharge or whether there was something more going on. Before we put any refrigerant into a system, we always carry out a pressure test first. There is no point topping up a system that has a leak, because you will be back in a few weeks with the same problem and you will have paid twice.

The AC System Was Pressure Tested Using Specialist R1234yf Equipment Before Any Work Was Done

This Mitsubishi uses R1234yf refrigerant, which is the newer type of refrigerant now fitted to most cars built in the last several years. It is not the same as the older R134a refrigerant, and you cannot service an R1234yf system with older equipment. We use a dedicated AC service machine that is specifically designed for R1234yf. It has its own set of pressure gauges, a digital readout, and connects to the vehicle's high and low pressure sides via colour-coded hoses, blue for the low side and red for the high side. The machine draws the system down into a vacuum first, then monitors whether that vacuum holds over a set period of time. If the pressure drops during that hold period, it tells us there is a leak somewhere in the system. On this Mitsubishi, the pressure readings came back well within range and held steady. That told us the system was sealed correctly and had no leaks we needed to worry about.

A Leaking or Low AC System Does More Than Just Blow Warm Air

A lot of people think a failing air conditioning system is just an inconvenience, something to put up with until it gets really bad. But there are a few things worth understanding here. The refrigerant in the system does not just cool the air, it also carries the oil that lubricates the compressor. If the refrigerant level drops too low, the compressor starts running dry. Compressors are not cheap. A replacement AC compressor on a car like this can run into several hundred pounds, and that is before you factor in the labour to fit it and the cost of evacuating and recharging the system properly. Catching a low refrigerant situation early, before the compressor starts suffering, is the difference between a relatively modest service job and a significantly more expensive repair. Beyond cost, in warmer months your air conditioning also plays a role in keeping you alert and comfortable on longer drives. It is not just about luxury.

The System Checked Out and the Car Was Confirmed Ready for the Warmer Months

Because the pressure test showed no leaks and the system was holding correctly, this Mitsubishi did not need any remedial work beyond the diagnostic check itself. The readings were solid, the system integrity was confirmed, and the customer left knowing exactly where they stood with their air conditioning. That is what a proper pressure test is for. It gives you a clear answer either the system is sound, or it is not, and if it is not, you know before you have wasted money on a recharge that would just leak straight back out.

At Platinum Vehicle Services in Walsall, we carry out air conditioning checks, pressure tests, recharges, and repairs on a wide range of vehicles. If your AC is blowing air that feels less cold than it used to, or if it seems to take much longer than normal to cool the cabin down, those are signs worth getting looked at. The same applies if you can hear an unusual noise when the AC compressor kicks in, or if you notice the system cycling on and off more than it should. These are all early indicators that something may be developing. Bringing it in sooner rather than later usually keeps the cost down considerably. If you want your air conditioning checked or serviced ahead of the summer, get in touch with us or book in through our website at platinumvehicleservices.co.uk.

BMW Air Conditioning Regas Service in Walsall

This black BMW came into us at Platinum Vehicle Services blowing hot air from the air conditioning. The owner had noticed it over a period of time, the air just was not getting cold anymore, and by the time it arrived with us it was putting out nothing useful at all on a warm day. That is a common pattern with air conditioning systems. They do not usually fail overnight. The refrigerant level drops gradually, performance gets worse, and then one day it simply stops working. We got it booked in, carried out a full inspection of the system, and then carried out a complete air conditioning regas service to bring it back to where it should be.

The System Had Lost Refrigerant and Was No Longer Able to Cool the Air

The first thing we do before any regas is put the system through a vacuum process. We connected our PRO series air conditioning service machine to the BMW using the blue and red hoses you can see in the video, one to the low pressure side and one to the high pressure side of the system. The machine pulled the system down to a vacuum of -0.95 bar and held it there for just over twenty minutes. The reason we do this is twofold. First, it removes any moisture that has found its way into the system. Moisture in an air conditioning circuit reacts with the refrigerant to form acids, and those acids will corrode the internal components over time, including the compressor, which is the most expensive part in the system. Second, holding a vacuum lets us see whether the system holds pressure. If the vacuum drops during that period, it tells us there is a leak somewhere before we put any refrigerant in. There is no point filling a leaking system. You would be wasting gas and the customer would be back within weeks with the same problem.
Once the vacuum held, we moved on to the oil and dye injection stage. The oil lubricates the compressor and the other moving parts within the circuit. Without it, the compressor runs dry and will eventually seize. The dye is a UV-reactive fluid that we inject so that if there is any slow leak present, it shows up clearly under a UV lamp during the flush test at the end of the job. This BMW uses R134a refrigerant, which is the standard refrigerant for vehicles of this age. There is a label under the bonnet, fitted by the manufacturer, which specifies R134a and gives the exact fill weight as 550 grams, with a tolerance of plus or minus 10 grams. We follow that specification precisely. Overfilling an air conditioning system causes excessive pressure and can damage the compressor. Underfilling it means it will not reach the correct operating temperature. Neither outcome is acceptable, so we charge to the manufacturer figure every time.

Leaving It Any Longer Would Have Risked Compressor Damage and a Much Larger Bill

When an air conditioning system runs low on refrigerant, the compressor is not just working less effectively, it is working under strain. The refrigerant in these systems also carries the lubrication oil around the circuit. When refrigerant levels are low, there is less oil circulating, and the compressor starts running with reduced lubrication. Over time, that causes wear on the internal components. A compressor on a BMW of this type can cost several hundred pounds to supply and fit, sometimes significantly more depending on the model. The regas itself is a fraction of that cost. So if your air conditioning is blowing warm or just not as cold as it used to be, getting it looked at sooner rather than later is always the more cost-effective decision. Waiting until it stops completely can mean the compressor has already been working dry for some time, and by then you may be looking at a more involved repair.

Full Regas Completed with 550 Grams of R134a, Oil and Dye Injected, and a Flush Test Carried Out

After the vacuum held and the oil and dye were injected, we recharged the system with 550 grams of R134a refrigerant to the manufacturer specification. Once the charge was complete, we carried out the flush test. This involves running the system and checking all the connection points and components under a UV lamp to confirm there are no leaks and that the dye we injected is circulating properly. The BMW passed the flush test without any issues. The air conditioning was blowing cold air correctly before the car left us, and the owner was satisfied with the result. The whole process, from vacuum through to final check, is done properly and in the right order every time. There are no shortcuts that are worth taking on a pressurised system like this.
Air conditioning is something a lot of drivers do not think about until it stops working, but it is worth having the system checked and regassed roughly every two years as a matter of course. The refrigerant does seep out slowly even on a system with no faults, and keeping the levels right protects the compressor and keeps everything working as it should. If your air conditioning is blowing warm air, taking longer than it used to get cold, or making an unusual noise when you switch it on, those are the signs to watch for. Any of those things is worth getting looked at before the problem develops further.
We carry out air conditioning regas and inspection services here in Walsall for all makes and models. If your car's air conditioning is not performing the way it should, get in touch and we will book it in. You can reach us and find out more about what we do at platinumvehicleservices.co.uk.