Self Re-Gas of the 156 Air Con using R134a+
The (2000) 156 Sportwagon aircon was putting out only micrograms of cool air so I purchased a re-gas bottle of R134a+ refrigerant from a well known high street chain.
The re-gas canister comes with a pressure gauge and connector which quickly tells one the state of the system. In my case it was pressured but low. To re-gas you have to have the engine running at 1500rpm which means you need to be very comfortable, confident and safe working very close to moving belts, pulleys and fans. The refrigerant does not normally leak out during this operation but you need to take precautions (gloves/glasses) as it can burn and the canister does get cold as the juice is going into the carís system. The R134a+ also contains lubricant.
The process is simple. First check is to see whether the A/C pump clutch is engaging. You need to look on the left hand side of the pump on the left hand side on the engine bay (viewed from front - it's near the front connected to the pipes with the gas ports on. You may need a torch to see the end of the pump. When you switch the A/C off the centre of the pulley stops turning. The whole pulley and centre spins with the A/C engaged. If it doesn't engage then you have some other issue or low pressure.
To re-gas, the canister is connect to the (smaller) low pressure port on the A/C (just behind the radiator) using the umbilical and connector. The pressure in the system then shows on the gauge. It may well show a very high pressure (in the red) when the engine is off. After starting and running for 3 mins or so and leveling the rpm out to 1500 the pressure should be in the blue/amber range (depending on ambient temperature Ė conversion table on canister). To re-fill the A/C squeeze the trigger for a few seconds and recheck pressure (following all manufacturers instructions Ė some even have tutorials on the Web)). I suggest letting each charge settle, warm up (paradoxically) and expand for 30 seconds or so before adding the next charge. This helps ensure that an equilibrium is reached otherwise it's possible to over-gas the system - which is a 'bad thing'. Keep the can agitated whist re-gassing (it will get quite cold). The whole re-gas takes about 10 minutes. It did improve the output from next to nothing to the usual 156 dismal something . I had a little fluid left so also checked my wifeís Peugeot.
If you get a kit and the pressure is reading completely zero when you connect it then I guess its 50:50 whether there is a more serious leak and you might be better getting it checked out properly first rather than wasting the contents of the can. If you know the history of you A/C; use it all the time and know it's generally working but the performance is slipping away then these kit's (or your local dealer) seem like a good idea. If you have to top up more frequently (monthly or so) then you've definitely got a leak and need to get it sorted. I'm pleased with the result so Iím likely to get a refill bottle so that I can periodically recheck the pressure using the original gauge (usually once each year).
It's nice to have some weather that warrants it (it's good for clearing mist too when it's raining)
Last edited by Camphorball; 27-06-10 at 18:09.