My AC is not working in my Elise 2012

[design4p]

Hi,

My AC is not working in my Elise 2012

I've check the fuses F7, F19 and C4 - All OK.

I've shorted the Brown/White (the live feed checked at 12v) contact to the Red contact on the AC/Fan Relay module and the compressor does not start or click.

Would this mean the compressor is faulty or could there be a different fault?

Regards John

[design4p]

Hi,

Me again.  Just looking at the price of a replacement compressor (just in case this is the fault) and I am getting a price of around £3,300.

This appears ridiculous.

 Would there be any way or reducing this?  Such as buying a reconditioned compressor or a non original Lotus part or a bag or bits to recondition the compressor as a DIY project.

Any suggestions would be most welcome.

Regards John

Edited June 26, 2022 by design4p

[EXCEL V8]

21 minutes ago, design4p said:

Any suggestions would be most welcome.

Maybe post in the Elise section! 😉 🙂

Pete

[design4p]

Hi,

More information - Both the pulley and the outer flange rotate together when the AC is switched both ON or OFF.  IE no difference.

Trying to understand what this means.

Any assistance would be most welcome.

Regards John

[Trunnion 74]

Hi John,

Was the aircon working and then just stopped or has it been stopped for sometime?

If it was working and then just stopped blowing cold then it is possible that all it needs is a top up as the pressure in the system has fallen below that which the compressor needs in order to activate the clutch.  The compressor is always being driven by the belt the important part is the bit on the end of the compressor the bit with all the holes in.  With the aircon turned "off" the holes on the end will be visible and not spinning.  With the aircon turned on and provided there is sufficiant pressure the clutch will engage and the bit on the end will start to spin and the holes will not be visible as it will be spinning too fast.  Aircon gas naturally dissipates out of the system and needs to be topped up every so often, usually after 4-5 years.  When topped up the gas has with it a lubricant and an ultraviolet dye in it.  The lubricant to lubricate all the seals in the system and the dye to show you if you have any leaks, get a UV/Black light "torch" and you can easily check for leaks if you need to

The good news is that top up kits are available STP sell two types the "STP Air Con Gas Recharge Kit R-1234YF" for newer vehicles and the STP Aircon Recharge R134a for older vehicles.  You will have a label somewhere under the bonnet which will tell you which type (my guess would be the older type).  Once you have one of these kits it's an easy ten minute job to top up the system.

If however the aircon has not been working for some time then the seals may have dried out too much and it will not hold pressure. Handily the kit comes with a gauge/trigger which will give you an indication if you should proceed with the top up.

The clutch is controlled by the A/C button.  However even with the A/C button off the clutch can still engage when the defog/clear windscreen switch is active as it uses this setting to dehumidify the air to clear/defog the windscreen and also to move lubricant around the system.

Turn all the blowers off and just have the A/C switch on and see what the bit on the end of the clutch does then.

Hope that helps

 

Roland

 

[Rambo]

Good post Roland. Very informative 

[Trunnion 74]

Thank you Rambo. I like to do my bit when I can.

[philcool]

First of all I belive the compressor won't run unless the blower fan is running as in my S2 Exige 

As to do so would allow liquid refrigerant to flood back and damage the compressor so first make sure you have the fan turning.

Secondly the biggest and most common leakage point is the glandseal on the input shaft of the compressor which require lubrication between the polished surfaces of the seal to minamalise refrigerant loss so if the compressor isn't run for a while the oil film is lost and leakage accours.

If the standing gas pressure in the system has dropped due to leakage there is a low pressure switch fitted that will inhibit the compressor from running as to run with a low gas charge will damage the compressor due to lack of cooling and lubrication.

The compressor is only cooled by the returning cold refrigerant gas from the evaporator and lubricated buy the mist of oil also contained within this refrigerant as the compressor has no sump .

Hope this helps 

[design4p]

Hi,

Thank you for the information.  Just wondering about the refrigerant level - as said if too low or too high the compressor will not come on.  However, would it be possible to turn the outer disc (clutch outer plate) by hand when the engine is switched off.

Hi Trunnion 74 - The AC has not worked for quite a while - I did have the refrigerant topped up (changed) at a garage with a AC machine- which they say cycles the process, ie removes, checks for leaks, and refills.  However, it still did not work.

Regards John

[philcool]

If you remove the drive belt the pully should rotate very easily as it just freewheels on a bearing.

When the coil is engaged it pulls the middle in by about 1 to 2 mm and engages the shaft of the compressor to the outer spinning driven pully.

Sometimes the coils fail you can test by connecting to 12v via the plug pay attention to the polarity if 2 wires in the plug if only 1 wire then it will be positive and negative through the body of the compressor. 

You should hear a positive click and see the clutch move into the pully and engage.

All 3 parts can be replaced pully,clutch,coil by roving the middle bolt and usually a circlip under the clutch,makesure on removal you  don't loose and spacer washers that are usually fitted under the clutch plate to set the clutch gap to pully.

If the access to the compressor is difficult you can remove the mounting bolts and leave the suction and discharge flexible lines connected and gain some movement to help accessibility but don't strain or kink the lines whilst doing so.

 

[ramjet]

18 hours ago, design4p said:

Hi,

More information - Both the pulley and the outer flange rotate together when the AC is switched both ON or OFF.  IE no difference.

Trying to understand what this means.

Any assistance would be most welcome.

Regards John

I've read through this as well. If the pulley and the coil clutch plate are both turning whether the AC is in the on or off position, you have a seized clutch on the compressor. Depending on how long you have not had cold air from the vents may give you an idea how long the compressor has been running without lubrication. I think it is safe to assume that it would be anytime you had the engine running since you noticed it. I'll let you add how much longer the issue may have been there before you noticed it. A good AC joint has to pull a vacuum on the system to regas it. If the seals are stuffed on the compressor shaft, the vacuum operation will most likely fail.

And yes, 3.3k GBP for a compressor is ridiculous. Even fitted, it's ridiculous. Find a good AC company and go there. A compressor here in Aus is about $500 max, so about 250 GBP, the fully electric ones are only asking about $1,200 AUD, so about 600GBP. Add fitting, leak testing and regaling and you can't get near 3.3k GBP. 

[design4p]

Hi Ramjet & all other people assisting,

So it appear the clutch has seized.  Unfortunately, I noticed this over a year ago and the local garage which has the recharging equipment did a recharge service but this di not solve the problem (most likely due to the now known seized clutch).

So it looks like bad news and a new compressor is required.

I'll contact a few AC specialist for quotes - Me in North Wales, LL21 0NA, UK.

Just thinking would it be possible to refurbish the compressor with new internal parts?

Any further assistance would be most welcome.

Regards John

[ramjet]

Refurbishing the compressor is not something you want to tackle. Could be a bit of a rabbit hole. You would be better off doing a part exchange with a reputable firm.

if you're handy with tools, fit it yourself.

Then back to the company for gassing etc

 

[philcool]

Yes these compressors cannot usually economically be refurbished by an individual. If its just the clutch that's seized and won't pull in then a new clutch and for the cost of it pully with idler bearing and coil while your at it maybe all that's needed.

Then a vacuum and regas may well be all that's needed . The only fly in the ointment is that the compressor if its not run for ages will almost certainly leak from the shaft seal as it will have dried out so will require a regas run then re vacuum and regas again.

I would have thought if the clutch was seized in the drive position then the compressor would have seized and more than likely thrown the auxiliary drive belt off or had it skidding round making a racket with usually lots of smoke.

If you've been lucky enough to catch it quickly then you may still get away with a new clutch assembly.

Fingers crossed 🤞 

[design4p]

Hi Philcool and all other people helping,

The situation is that both the drive pulley and the end plate rotate when the AC in ON or OFF.  However, there appears to be a gap between the end plate and the drive pulley which does not change with AC On or OFF.  Please see earlier photos.

I'm a eager amateur engineer rather than a professional vehicle engineer.

It would be good to know that if both drive pulley and the end plate both continuous rotate (AC On and OFF)- but the gap remains the same - Is the actual compressor being driven?

Hi Philcool,  Great information all noted - Just to say the auxiliary belt is still in place and appears to drive the pulley without a noise concern.

Regards John

[philcool]

I belive you have a cluchless compressor fitted and so no magnetic cluch is fitted so the compressor runs all the time and it's output is regulated by a gas pressure controll solinoid within the compressor that regulates the angle of the swash plate within the compressor and thus the piston stroke.

Unfortunately I've not worked on one of theses systems but understand that the compressor is always lubricated by a special expansion valve that always returns oil to the compressor even when cooling is not required and so would explain your high quoted cost for a replacement compressor verses an older electro mechanical clutch type compressor.

As the newer cluchless compressors are controlled by many different factors such as engine speed ,ambient air temp,cabin air temp,and the fact that the controll solinoid can also fail a simple diagnosis is I'm afrade not that easey.

I do hope that a technician trained on these systems can pinpoint the fault with the correct diagnostic equipment.

It may be the system is just undercharged.

Again fingers crossed 

 

[design4p]

Hi Philcool,

That is very good information Re Cluchless Compressor.  

I have purchased the STP Aircon Recharge package and will use this when it arrives in the post.

Also I will contact my local Lotus dealership (Cheshire) for clarification on the type of compressor I have.

I agree a AC compressor should only be a few hundred pounds not £3,300.

I appreciate your assistance and all other comments made.

Regards John

[philcool]

Remember when recharging please don't get carried away with the notion of more refrigerant the colder and better it will be.

The only real way of recharging the system is to vacuum and charge by weight.

There are many variables when topping up such as engine speed,ambient air temp,interior fan speed. Thus topping up with the STP option is a bit of a gamble as it's guid is pressure only via a gauge.

But i understand its your only option,if you are topping up remember the golden rule fare better to be slightly undercharged than overcharged good luck 👍 

[design4p]

Hi Philcool,

Thank you for your assistance.

Called my Lotus dealership (Chester Parts) and the £3,300 quoted for a Lotus AC compressor has reduce to £299 + VAT for a (Non Lotus part) - Presumably a Toyota AC Compressor.  Which seems logical as the engine is a Toyota.

Maybe on the way to a solution now with your assistance.

Regards John

[design4p]

Hi Philcool

Used the STP package - There was very little or no gas in the system.  Went through the process and filled as instructed.

Unfortunately still no AC cooling.

I would appreciate your view on the latest situation.

Regards John

[philcool]

So you connected the STP canister and it was reading a low pressure below the green I assume.

You added refrigerant and ran the A/C and did you notice the pressure again drop and you added more refrigerant.

At this point as you were adding refrigerant with the system running did the pressure whilst running and adding refrigerant come back into the green or is it a case you kept adding and it just kept dropping away in which case the compressor is pumping but the expansion valve is closed.

Or was it the case you topped it up ran the A/C and the needle never moved in which case the compressor is not pumping 

[design4p]

Hi philcool,

Sorry not sure about what was actually happening at that point I was adding refrigerant whilst reading the instructions - ie adding for short bursts and then wait and then again until the gauge was in the green.

However thinking about it - after a 10 second burst the needle dropped a little and then the needle increased at each burst of gas.

Another thought - initially I was told to check the relay module and short the brown/white with the red (giving power direct to the compressor) and to listen for a click from the compressor.  However, would this only be possible if the compressor was a magnetic clutch - thinking with clutchless compressor there would not be any click.

Is it possible to test the relay module on a clutchless compressor?

Can you suggest anything I should do

Regards John

[philcool]

Yes you can link the relay out on a magnetic clutch compressor while the engine is off and see and hear the centre of the clutch pull into the pully I can hear my clutch engage and the revs rise on my s2 exige from inside.

But looking at your clutch in your pictures it looks like a constantly running clutch I stress looks.

I would re connect the STP gauge and your need 2 people and look at the gauge pressure with the engine off start it rev to 1500rpm does the pressure drop down or not turn the A/C on with the internal fan on 3 and again rev to 1500rpm does it drop down if not then the compressors not pumping. 

Now if its not then either the compressors running and has an internal problem or its not turning and that could be an issue with the clutch.

I looked again at your pictures and can't see any wires on a plug behind the pully maybe if ypu have a closer look you should be able to see 1 or 2 wires going to a plug behind the pully as that's where the coil is situated on a magnetic clutch 

Keep at it John nothing ventured nothing gained .

Just a thought does your A/C switch have a light in the middle mine does and shines blue when A/C is called for just a thought 

 

[EuropaSman]

@design4p just a heads up in case you do end up needing a new compressor, Bell & Colvill have  an OE one listed on Ebay for £1795. It's still pretty expensive, but a lot cheaper than the £3300 you were being quoted.

Link: https://www.ebay.co.uk/itm/174545385182?hash=item28a3b736de:g:CMIAAOSwknBfyk3B

[design4p]

Hi Philcool,

Engine off - Needle very high in the middle of Alert

Engine on @ 1500 Rev & AC off -  No movement of needle

Engine on tick over AC on full - needle moved through the green to the top of the white.

Engine on @ 1500 Revs and AC on full - very slight wriggle but nothing really.

Regards John