aircon

sheldon6 · Post by **sheldon6** » 17 Jun 2004, 01:37

can anyone help?
I have a 98tdlx est, last summer i had the system re-gassed and all was well, icy cold and both fans running whilst the switch was green.
recently the car does not get quite as cold and is not good enough to chill the cabin during this tropical spell we are having. i hava also noticed that only one fan cuts in and out intermittently, the pupmp runs and there is gas / bubbles in the sight glass. i have checked all fuses and the relays that are situated between the fans
Any help would be grately appreciated.

monkeyman · Post by **monkeyman** » 17 Jun 2004, 02:37

Hello!
It could be its lost a bit of gas, they do over time anyway. A good check you can do is switch the air con on / engine running. Check the temp of the air coming into the condensor at the front of the car, then check the temp of the air coming through the center vents inside the vehicle. There should be a 10 to 12 differance in temp. If its not, then check the front condensor for leaves and bugs etc. If ok then double check the fans for correct operation
Good luck.

Richard Gallagher · Post by **Richard Gallagher** » 17 Jun 2004, 03:13

Have you been using the aircon regularly throughout the winter, i.e. at least 10 minutes every fortnight?
If not then there is a good chance that the seals have dried out thereby allowing the gas to escape.
Apart from the system being filled with gas it also has an oil lubricant which drops to the bottom of the system unless the system is used regularly.
The gas/bubbles you can see in the sight-glass doesn't mean a lot with newer systems/gas compared with those of years gone by, I would however get the non working fan sorted out, (both of mine work in tandem). This obviously will not help the aircons efficeincy.
Just in case you didn't know, when it is really hot/humid then put the air intake onto recycle, this helps the aircon because its not continually taking in hot air, but the cooler air from the cabin.

sheldon6 · Post by **sheldon6** » 17 Jun 2004, 04:21

thanks for all your replies.
the system was regassed last summer and i have run the system pretty much all the time.
i have cleaned between the rad and intercooler as there was lots of leaves and have power washed throught. the air blows cold and the pipe to the sight glass gets hot so i presume that it is removing heat from the car.
is there a possiblity that the one fan is running fast to compentsate what could be a duff fan and is there an easy way to get to the wire to test for juice, but i am still mystified as to why the fans dont run at half speed contunuasly as they did before when it was low on gas.
hmm, puzzler, great forum and thanks again

alan s · Post by **alan s** » 17 Jun 2004, 04:57

Could be that one fan has thrown in the towel and the fan that is operating is being triggered by the HP switch on top of the receiver/dryer that cuts in when the head pressure gets too high. If only one fan is operating when it should be two, the gasses won't be condensing in the condensor and as a result the low pressure side will also be all out of whack affecting its cooling capacity.
I'd suggest getting the fan that's not going tested and if in doubt change it. I'm not sure on how it operates but it is possible that each fan has it's own relay and if the fan checks out OK, that should be the next port of call.
Alan S

tomsheppard · Post by **tomsheppard** » 17 Jun 2004, 14:15

These fans are wired in a silly way. To run slowly, they are wired in series but to run fast they are wired in parallel. This is done with two relays. If only one fan works then you have no low speed available at all. Yippee! nice easy diagnosis. If one fan has become disconnected then you won't get good aircon and you will be risking the engine.
Fault tracing: Short the low speed switch contacts on the plug connected to the radiator. Nothing will happen I reckon. What should happen is that both fans should run slow.
Now short the duff fan out at the fan connectors.
No change? wiring to fan
other fan kicks in fast? duff fan is bust.

wotsupnow · Post by **wotsupnow** » 17 Jun 2004, 15:14

The fans appear to be identical to Pug306, goto this link
http://www.peugeotlogic.com/workshop/base/workshop.htm
and then electrical (top right) then 306cooling fans on left.

wotsupnow · Post by **wotsupnow** » 20 Jun 2004, 18:52

Following the Pug diag I just mentioned I have fixed my Xantia fans prob. The 12v supply to the single relay ( not the pair ) measured only 10v and when a bulb was put on that connection at the relay socket it dropped to 0v !, I took a wire from here via a 5A fuse to the fan supply on the same relay which fits neatly under the relay cover and now both fans run as they should, wnet for a run up the motorway and around town and engine temp stayed pretty constant halfway between 60 & 90 and the aircon managed to frost up the windscreen above the vents. The feed that must have a high resistance connection somewhere is off fuse 14 inside, fuse measures 12v both sides so I guess theres a multiplug involved somewhere.
Pete

wotsupnow · Post by **wotsupnow** » 21 Jun 2004, 17:38

Update, the car has a lot more ooomph than previously !
I guess this is because the intercooler now has more air flowing over it a: because I cleaned all the vegetation out of its fins when I replaced the radiator and b: because the fans are running again, without fans I doubt there'll be much airflow as the grill opening is quite small then there's the a/c condensor - intercooler - radiator to get past and then the engine , in fact where can the air exit other than going around the engine and out under the back ?
Pete