When we test your car and find you have no gas in the system we charge £10 for a Nitrogen test leak and spray a bubble solution on the condenser and pipes to highlight any potential leaks in your system. We also add UV dye to show future leaks. We only charge a £15 for a UV check, or half price service if it needs regassing within 3 months.
A nitrogen leak test will identify 80% of leaks. The test will not detect "High-Pressure Porous Leaks" This is because Nitrogen molecules are 10 times bigger than the refrigerant molecules and Nitrogen can only pressurize to 150psi. On a hot day, your car reaches pressures of over 300psi, which can cause the refrigerant to leak, due to potential high-pressure porous leaks, that the nitrogen test cannot detect.
Adding Extreme leak seal will rectify 90% of leaks, but when the AC system reaches high pressures, holes can then expand above 0.3mm which the sealer cannot repair. We can only check visible components of the AC system, we can not check evaporators or some compressors or hidden pipework for leaks, The pressure will slowly drop if a leak is apparent in most cases when under 150 psi of pressure, but we can not test above 150psi, so there is a potential it could leak due to higher pressures in operation in hot weather.
We believe the customer must be informed of the above information before deciding whether to have a regas or adding Extreme Leak Sealer.