Frequently Asked Questions

SOME COMMONLY ASKED QUESTIONS ABOUT CAR AIR CONDITIONING SYSTEMS


Q: Can I top up the gas in the air conditioning myself - I've seen small DIY cans on sale?
A: We strongly advise against using any kind of DIY kit to refill the AC system yourself for several reasons. Firstly your car needs a specific quantity of refrigerant in it. This could be 500 grammes or 1,500 grammes. The only way to accurately measure the amount of gas in the system is to evacuate it and add a specific weight of refrigerant back in. Over filling can cause more damage than under filling. Secondly R134A refrigerant boils at around -26° C when under normal amospheric pressure. R134A is present in liquid and gas form under pressure within the vehicle AC system. If you get it on your skin it will cause severe frostbite and if you managed to squirt it into your eyes then you would have no need for a car any more! There are many other reasons which we won't go into here but bear in mind it is illegal to work on vehicle AC systems unless you are licensed to do so and there is a good reason for that. Don't try and save £10 by doing it yourself and risk expensive repairs or personal injury, leave it to the professionals who are trained to do it properly.

Q: A guy in a white van offered to recharge my AC for £20 and said it would only take 5 minutes. How can he do it so cheaply and quickly?
A: We have heard some alarming stories recently about certain dodgy people recharging systems on the cheap. These people simply add propane gas by letting the compressor suck it in. Propane is cheap and can be used as a refrigerant, it is also used in caravans which is where we suspect these shady operators usually live. However propane is explosive and with the condenser at the front of your car full of it you would be driving around in an unexploded bomb! Remember too that the guy will not have vacuumed your system to remove moisture which will form ice, plus you have no way of knowing how much gas is in there - and both of these can cause damage. Always ask to see proof that the person working on your car is qualified to do so - nobody genuine will take offence at this!

Q: Is it true I should use the air conditioning all year round, even in winter?
A: We recommend you use the air conditioning year round regardless the temperature your heater is set to. AC is not just for cooling - it also removes moisture from the air so prevents misting of windows. Also modern cars are very efficient and you should not notice any increase in fuel consumption. If you prefer not to have the AC switched on constantly then you should run it for at least 10 minutes once per week. This will ensure the refrigerant and oil circulates and prevents the seals from drying out which can cause them to leak.

Q. Can you put an additive into the air con system to seal leaks?
A. There are products you can purchase which claim to seal up leaks. We would never recommend using these. Firstly we have seen vehicles which have had these added and they were still leaking so they don't seem to work as intended very well. A corroded and battered condenser which is full of holes really needs replacing with a new unit. More worryingly, leak stop additives often cause compressor failure as they cannot distinguish between a hole that needs to be sealed and the small openings that are part of the air conditioning system itself. (Refrigerant is pumped by the compressor through a valve which is essentially a small hole or set of holes and this is where the cooling occurs). If your compressor fails due to a leak stop product having been added then you will not only need a new compressor but the whole system will need to be flushed (cleaned out) to get rid of the rogue sealant and any parts that cannot be flushed such as the condenser, evaporator and valve will need replacing. This would be a four figure job and not economically viable on most vehicles - plus we wouldn't be prepared to do it anyway as you cannot guarantee the system is 100% clean again after flushing it. We recently worked on a vehicle where one service valve was almost welded in place by some kind of leak stop product and the whole pipe which housed the valve needed replacing before we were able to connect a manifold set to the car and diagnose the fault with the air conditioning.