Air con troubles

[Burgunder]

Hi all ,
I'm after some advice on an air con fault on old Merc R129 sl 500 with early air con. The one with just a few dials. Not the common dual sided system.

Basically I have no air con. I believe the compressor pump isn't running. I have had it in to two Indy air con recharge places. Both have full modern Bosch air con recharge stations. And both came across the same issue and were clueless as to why or how to proceed. Basically when the Bosch system is connected on auto mode it first removes the old gas. Then it vaccums the system and monitors it for a period to see if it can see any pressure loss. If that passes which mine did every time it then goes to recharge the vehicle. However at this point after approx 0.3100 to 0.500kg of charge had transferred it pauses for some time before failing. If the process is repeated it seams to load a little more by about 0.100 each time. I have tried this cycle four times on two machines. Any ideas why it's failing to fill? What can be checked?

 

[whirsk]

Hi there,
Is the compressor running during recharge of refrigerant ?
What is the correct factory charge of refrigerant?
Has there been any work done on car recently new pipes/coolant hoses etc ?

Sent from my SM-G920F using Tapatalk

 

[Burgunder]

Hi thanks for your reply. The technician doing the recharge said the engine and pump remains off during the full cycle. There has been no work done but air con history is unknown as car has been in storage for few years. Are you supposed to run while filling then?

 

[Burgunder]

Forgot to say correct quantity of refrigerant is 0.900kg apparently.

 

[Trickythemerc]

The engine should be off when recharging the aircon,if the machine is shutting down mid cycle it should tell you what the problem is on the print out.

 

[Burgunder]

Thanks again for your time to reply. I have the printout. There is no mention of any error on it. Just all the amounts listed. Bosch at top and model SL r129. It says, no gas recovered, no oil recovered, vaccuum time 001.00 min, leak test NO LEAK DETECTED and it charged 0.495kg. I watch the machine when it was running and when it got to filling gas it counted up very quickly to 0.500kg then slowed to a stop and crept down to 0.495kg over about 10 mins before timing out. With an error unable to complete fill refur to manual or similar. The ignition was off.

 

[ivan1983]

Im sure whe I have had my aircon done the engine was running, im not an expert.

I guess each time it fails they drain the system so you cant check if the compressor functions.

 

[Burgunder]

Ok Ivan, cheers again. Need and answer on this anyone. Should engine run when filling? Gonna try shorting pressure switch next to see if compressor will kick in. Might lead somewhere.

 

[cass]

cass

I know your a long way from Preston,Lancashire but you could give a company called "chill out" a call he just sorted out my wifes Honda air con out he is a car air con specialist his tel No is 01772 603000 or mobil 01704331537 the address is Long Fold Farm,North Road,Leyland,Preston,PR26 9AY. he is called Chris & seems to know his stuff,hope this is helpful.He can be hard to contact as he is quite busy.