BMW 5 Series (E34) Condenser Change

If your BMW air conditioning has stopped working the chances are you have lost most or all or your system refrigerant. The fastest way of finding out is to attempt to have the system refilled by a specialist. They will evacuate any remaining gases and then pressure test the system before refilling. When mine was pressure tested it was immediately obvious that there was a leak somewhere within the condenser matrix situated in front of the engine radiator.
I was shocked to be quoted £500 for the work by a local specialist so decided to carry out the work myself. A replacement condenser cost me £130 in the UK including VAT and I would estimate the time required for the job to be around 2-3 hours. Allow a little longer if you intend to clean up any corroded pipes while you are in there. A test and re-gas once the work is completed is around £60. Make sure the system is totally depressurised before doing anything – releasing any remaining refrigerant is bad for the environment and also illegal.
First of all, get the car off the ground – get the front wheels clear of the ground and supported on axle stands or ramps. You will need around 1.5 feet to remove the condenser from below. Open the bonnet and remove the trim from around the headlamps. You do this by releasing two plastic clips either side of the outer lamps with a long screwdriver and then pulling gently. 4 clips situated in the centre grill also need released before removal – this is documented in the headlamp section of this site. Get underneath the car and remove the plastic/rubber trim situated immediately behind the bumper on the bottom of the radiator housing that runs the width of the car. This is secured with around 8 plastic expanding plugs. Next, you need to remove the front bumper – this is a lot easier than you may think and makes the job a great deal simpler. Carefully prise back the plastic trim either side of the number plate. This reveals two large nuts (17mm I think) on either side, which hold the bumper assembly to two crash absorbing tubes. Loosen these off – you may need a little WD-40 as the steel/alloy combination makes for some stubborn corrosion. Disconnect any wiring that goes to the bumper – fog lights and temperature sensor. Tape any stray ends back out of the way to help later.

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