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Old 20th April 2019, 18:22   #1
donc
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Default Air con

I have not yet owned my 1.8t in hot weather (but I hope to soon!). Problem is the air con is not working. Is it likely to simply need re gassing or is there anything else I should look out for? Advice would be appreciated.
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Old 20th April 2019, 19:00   #2
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Check that the low speed radiator fan works as it should. The aircn system uses it to operate. Search for 'Demist Test' to find how to test it. If the fan doesn't work it'll need the low speed resistor replacing. These are vailable from forum traders, eBay and electronics outlets. Loads of threads on this including HowTos.

If the low speed fan is OK, check that the condenser mounted on the front of the main radiator has plenty of fins left. They lose the finning after a few years and the aircon needs this to operate. You have to remove the front bumper to check.

Finally, have the aircon system checked over by an aircon specialist and regassed if necessary.

TC
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Old 20th April 2019, 19:37   #3
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Default Air con

Thanks for that. Seems like there's more to it than I thought!
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Old 20th April 2019, 22:34   #4
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If you take it to an aircon depot first, they ought to be able to diagnose any of the factors that will cause it not to operate. The chances are it simply needs a regas, but those other things are vitally important.


TC
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Old 20th April 2019, 23:37   #5
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Also check the wire that goes down to actuate the compressor....when my AC stopped working my wire was completely missing. What had happened was in the winter my auxhillary belt had snapped and unbeknown to me also ripped out this actuating wire. When i switched the aircon on in spring I got no cold air at all as the compressor wasnt engaging.
Bit of a long shot but worth a check to see the wire is in place and plugged in
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Jobs done with help from this forum:-

Head Gasket/Belts/Water Pump.
T4 session and spare key fob reprogram (thanks BigRuss).
Shannon Tube Replaced.
Boot Leak fixed.
Bonnet Cable fix.
Additional Boot LED lights fitted.
Plenum Drains cleaned.
Air Bag warning light.
Low Fan Speed Resistor Replaced.
Drivers door central locking (thanks Unclefista).
Handbrake compensator mod (thanks Harry).
Alloy Wheel Refurb.
New Turbocharger.
190 front brakes/caliper/discs upgrade.
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Old 21st April 2019, 06:34   #6
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As T-Cut states take it to an AC specialist. I didn't do that and ended up buying a pump and the condenser/desiccant unit plus a lot of other bits. It turned out to be just the condenser/desiccant.
Jules supplied all the bits and the knowledge!
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Old 17th March 2020, 18:24   #7
Fred Byrne
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Default Air condition wiring

Quote:
Originally Posted by louis71 View Post
Also check the wire that goes down to actuate the compressor....when my AC stopped working my wire was completely missing. What had happened was in the winter my auxhillary belt had snapped and unbeknown to me also ripped out this actuating wire. When i switched the aircon on in spring I got no cold air at all as the compressor wasnt engaging.
Bit of a long shot but worth a check to see the wire is in place and plugged in
I am re-assembling my wiring after engine removal. I was helped by an over-enthusiastic friend he may have removed the wire to the compressor. I do not recollect ever seeing it but darned if I cn find it now. So, where does it come from ? does it have a colour? and does it exist at all in later models? It's nor urgent but it would help to find it whilst the car is in bits.

Many thanks

Fred
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Old 17th March 2020, 18:33   #8
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Quote:
Originally Posted by T-Cut View Post
Check that the low speed radiator fan works as it should. The aircn system uses it to operate. Search for 'Demist Test' to find how to test it. If the fan doesn't work it'll need the low speed resistor replacing. These are vailable from forum traders, eBay and electronics outlets. Loads of threads on this including HowTos.

If the low speed fan is OK, check that the condenser mounted on the front of the main radiator has plenty of fins left. They lose the finning after a few years and the aircon needs this to operate. You have to remove the front bumper to check.

Finally, have the aircon system checked over by an aircon specialist and regassed if necessary.

TC
Probably best to get it leak tested before re-gassing as well- otherwise the gas (refrigerant) will only leak out again.

When i investigated mine, there was a oily stain around one of the pipe on the condenser and when I looked closer the fins in the condenser were also falling apart so ended up replacing it with a new one. I got a mobile air con engineer to come and do mine, first degas it and then re-gas and test before putting the front end back together (much better to do that than find out it leaks after you've put the front end on)
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Old 18th March 2020, 08:44   #9
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Quote:
Originally Posted by Fred Byrne View Post
I am re-assembling my wiring after engine removal. I was helped by an over-enthusiastic friend he may have removed the wire to the compressor. I do not recollect ever seeing it but darned if I cn find it now. So, where does it come from ? does it have a colour? and does it exist at all in later models? It's nor urgent but it would help to find it whilst the car is in bits.
I've offered help in your other specific thread Fred.

Simon
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Old 23rd May 2020, 19:05   #10
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Am having an air-con problem.

System had a re-gas last June. The fan was replaced a few years ago.
Have used the system periodically through the winter to keep it oiled.
Demist test shows fan changing from low to high speed (late car with just two speeds).
Compressor engages when air con selected so must have gas.
Simply no chilled air at vents
System test holding Auto and distribution buttons gives FC 00 so looks fault free.

Thinking it might be the fins on the condenser but before I take the bumper off can anyone suggest any other things to check ?

Many thanks
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