Air Con - doesn't work - what and where to check

[rizla603104]

Hi there, I know from last year - I really need to get the aircon working before the summer. I does not work. It does nothing after I turn the switch. I understand from GST who had a quick look - that it wash;t holding a vacuum. Where to start looking?

[dodge1979]

The clutch wont engage on the pump if the system is seriously low...a safety precaution to save wrecking the compressor. Where to start? Simplest thing is to get an aircon specialist to fit compressed air source onto the filling valve a simply listen to where its leaking out. This will tell you the area to attack firstly...

[fflyingdog]

As above ,get a specialist out,the connectors are in the engine bay you may have to remove the undertray(almost certainly) to get to the Hi and Low point connectors.It may have just leached out or you may have a leak on one of the component pieces.I ended up replacing the compressor i managed to source a second hand re-conned unit,have to say it was a pain to replace it but it works well in the summer although not up to modern 'boxes' standard.

 

      Nick S4s

[benjamincalleja]

Help my fans are working, cutting in when the engine gets to about 90-99 and then cutting out again at 80 but if I turn the aircon knob nothing happens anymore, it used to energise the fans? I can hear the the clicking if the relay but nothing happens? Where do I look? It can't be the relay because the fans obviously still work? Unless they are on separate relays??

[superdavelotus]

Pressure is too low in aircon system. Mine was the same until I had it regassed last week. Works fine now. As they are gassing the system, they do a vacuum test. Also if you have a small leak, they can add dye to the gas to locate the leak. I was lucky as mine retained the vacuum and then the gas.

Your description of fans cutting in at different temperatures is correct and has nothing to do with air con operating.

[benjamincalleja]

But if I turn the aircon knob shouldn't it always energize the radiator fans regardless of whether or not I have any r134a in there or not? Turning the knob makes a relay somewhere make a click noise but the fans don't energize like they always used to?

[Bibs]

It won't run as the gas contains lubricant for the compressor...

[rizla603104]

As Bibs says - the relay clicks but nothing else starts. That is normal for a Lotus A/C system that does not have any coolant in it.

[benjamincalleja]

...which brings me to the real crux of the matter then, where the hell does all my refrigerant keep going!!! Damn leak somewhere hmmmmmmmmm. Thanks guys I'll investigate...

[Alex Carter]

Air con pipe inlets are under the car inside the frame if your stood at the back facing the car there under to the left of the belts

[benjamincalleja]

What through the center of the chassis tunnel? Christ. How accessible.

[rizla603104]

no one said it'd be easy

[Alex Carter]

No silly just behing the turbo passenger side tuts

[rizla603104]

well one of my goals is to have the aircon sorted - at the same time I get a new radiator - makes sense to do that. It was also suggested to get the brake pipes replaced as well?

[Qavion]

I've been told by Club Lotus here in Australia that the newer gas has smaller molecules and that the original Lotus pipes are basically porous to this type of gas. They recommended a hydrocarbon based refrigerant such as HyChill. There is a debate running on how safe this is, but 1.2 million vehicles here run with hydrocarbon based refrigerants.

I've had a couple of leak checks carried out without success, but just haven't got around to trying HyChill. I'm not sure what the equivalent brands are in the UK.

[Clive59]

The standard refrigerants are more toxic, and less efficient than the HyChill type. Read some very interesting docs on HyChill, and makes sense. The risk is minimal I think, and considering the amount in a typical system is way less than a kilo. Let us know how you go, I will probably go the same path with my Elite when I re-attach the aircon. Are you using a more modern compressor? I know mine is massively heavy, and there must be better alternatives.

[amoss]

My 1991 Excel was converted to the newer gas which does have smaller molecules. after changing the fittings for the recharge the air con engineer pressuried the system using nitrogen with a fluorescent dye to check for leaks. None were seen and the pressure held. As a precaution the system was first charged with what the engineer described as  the air con equivalent of Radweld and the newer gas was then installed. Seems to work.

[910Esprit]

I changed my derelict R12 system to R134 by looking at youtube videos and asking basic questions online...  Made my own hoses using a modern non-porous versions and replaced the compressor, added the appropriate amount of PAG oil and recharged - Its still fine one year on....   

[EuropaSman]

I've been doing some reading up, as I've been toying on and off with the idea of an Esprit X180 stablemate for my Evora (or possibly even an Elan M100 - depends on how much I'm going to spend), but it must have aircon - I get very hot feet in the summer!. I understand that R12 was the refrgerant used up to about 1993 and the gas had larger molecules compared to R134a. I've found a few websites that suggest RS24 (also known as R426A) as a "drop in" replacement for R12.

From the Refrigerant Services Inc.website (http://rscool.com/rs-24/):

"RS-24 is a non flammable blend of HFC 134a, HFC 125, butane and isopentane which has a zero ODP and is also compatible with both traditional and synthetic lubricants so that a retrofit is not required. RS-24 is a “Drop-in” alternative for R12 which also provides a long term solution at the same time. It provides, therefore, a one change solution to the replacement of R12 at minimal expense. Because there is no need to use expensive and hygroscopic synthetic lubricants, the risk of moisture ingress into a refrigeration system is completely avoided. RS-24 has lower discharge temperatures than R12 thereby reducing degradability of the lubricant in the system."

"RS-24 can be used in all the main applications used where R12 is present including mobile air conditioning, hermetic and semi-hermetic compressor systems, cold stores, refrigerated transport, dairy chillers, vending machines, cellar cooling etc…

RS-24 is an excellent performance match for R12 providing a similar performance in almost every respect."

The webpage includes a lot of additonal information including details on the conversion procedure.

One provider of such a service I found is a mobile one in Kent: http://www.subzeroac.co.uk/

 

 

 

Edited February 19, 2016 by EuropaSman
Re-doing my English - doh!

[MikieP]

Mine was leaking at the o-rings in the filler valves located under the car near a wheel well! Another small leak from the compressor shaft seal. Once replaced, all was well. Kept R12 as some is still available here.

[rizla603104]

Just thought I'd update you on the outcome. It was decided to park the issue until the radiator needed replacing. Actually a few things needed doing at the front of the car - including new brake pipes. The main radiator had practically rotted out - but was still holding water - just. charge cooler / air con radiator was shot. In fact it looked like it had been like that for many a year. The condenser drier - was full of water. In all it was a bit of a mess. Having the radiator re-cored and new rails - as the old ones had pretty much disappeared the new double charge cooler and aircon system was installed. Finally it held charge. I had it converted over to the newer gas and all seems to be well. Now just need a few hot sunny days to give it a good test! So finally - everything works in my S4 Esprit. Also had a new cam belt and oil change done at the same time. Although I am lighter in the pocket - I now have the car where I want it!

[Jacques]

Did you use the R24?

Kind regards,

Jacques.

[lotusesprit1]

R413A works well if you can get it I have tried it on other ex R12 systems