Help with non-working S4s Air con

[glynherron]

Hi Guys,

the air con on my 1995 S4s isn't working.

When the interior 'heater' fan switch on full, and the air con switch

is fully rotated the fans can be heard to start running, and the

engine speed increases slightly. It has just been evacauted and

vacuum tested and found to be OK.

950 grams of R134a has been put back in. - just found out it should be 1000grams

But the air is still not being chilled.

Has anyone else had symptoms like this?

We are having a great summer (well compared to what we are

used to...), and it would be nice to fix it.

Many thanks in advance

Glyn

[LotusS4S]

I had somewhat of the same issue with my S4S. My mistake was in the way I recharded my AC. What I thought was 2lb of R134a was really much less. I ended up putting an extra 1lb of R134a but kept the AC on high w/ fan on high while the car idled for about 15minutes. I felt it was TOO much time but I have had COLD COLD AC blowing for close to 5 months now. I also noticed that the more I used the AC, the better it works.

Ed-

Hi Guys,

the air con on my 1995 S4s isn't working.

When the interior 'heater' fan switch on full, and the air con switch

is fully rotated the fans can be heard to start running, and the

engine speed increases slightly. It has just been evacauted and

vacuum tested and found to be OK.

950 grams of R134a has been put back in. - just found out it should be 1000grams

But the air is still not being chilled.

Has anyone else had symptoms like this?

We are having a great summer (well compared to what we are

used to...), and it would be nice to fix it.

Many thanks in advance

Glyn

<{POST_SNAPBACK}>

[glynherron]

I had somewhat of the same issue with my S4S.  My mistake was in the way I recharded my AC.  What I thought was 2lb of R134a was really much less.  I ended up putting an extra 1lb of R134a but kept the AC on high w/ fan on high while the car idled for about 15minutes.  I felt it was TOO much time but I have had COLD COLD AC blowing for close to 5 months now.  I also noticed that the more I used the AC, the better it works.

Ed-

<{POST_SNAPBACK}>

Thanks Ed,

just to clarify what you did...

Filled with 2lbs, then with engine running and air con on full with heater fans on full, filled with another 1lb?

Is it possible to overfill the system? What would be the effects?

TTFN

Glyn

[LotusS4S]

Overfilling is BAD.. but I purchased the R134a kit with gauge ($27) (2cans of R134a). The gauge indicated that the system was not full. Yes... The AC on FULL and vent fans on FULL. THis took me 15min for the system to suck in (lack of a better word) the last can. I noted that it took a LOT longer than I thought for the R134a to go through the system. I kept an eye on the gauge to make sure it was not going into the "red" zone.

Hope this helps.

Ed-

Thanks Ed,

just to clarify what you did...

Filled with 2lbs, then with engine running and air con on full with heater fans on full, filled with another 1lb?

Is it possible to overfill the system?  What would be the effects?

TTFN

Glyn

<{POST_SNAPBACK}>

[lotus4s]

Thanks Ed,

just to clarify what you did...

Filled with 2lbs, then with engine running and air con on full with heater fans on full, filled with another 1lb?

Is it possible to overfill the system?  What would be the effects?

TTFN

Glyn

<{POST_SNAPBACK}>

Glyn,

Overfilling is not good and you really should use gauges to get the correct amount installed but there is a high pressure switch which will shut the system off if the pressure gets too high from too much coolant. If that happens, just let some of the R134a out until it starts working again...

Jim

[TimRdLotus]

Is the compressor engaged? You can usually hear it click in and out. If it's engaging, but not cold than your low on R 134a. If it's not engaging, then you could have a number of problems i.e. low R-134a, compressor fuse blown. Get a 12 test light and start at the compressor wire, check for 12 volts, if you got 12 volts, and the compressor is not engaging, then you got a compressor or clutch problem. If you don't have 12 volts, start back tracking it to the compressor relay, then the fues which are located in the back engine compartment. I'd check the fuse, it's a 10amp fuse next to the relays.

Mine had a bad fuse holder, replaced the fuse holder and ac works great. It's usually something very simple.

Good luck.

[alan]

Overfilling is BAD.. but I purchased the R134a kit with gauge ($27) (2cans of R134a).  The gauge indicated that the system was not full.  Yes... The AC on FULL and vent fans on FULL. THis took me 15min for the system to suck in (lack of a better word) the last can.  I noted that it took a LOT longer than I thought for the R134a to go through the system.  I kept an eye on the gauge to make sure it was not going into the "red" zone.

Hope this helps.

Ed-

<{POST_SNAPBACK}>

Hi - what kit is this. To be able to re-charge your own AC for $27 seems like a bargin to me!

Thx

Alan

[glynherron]

Guys,

the pump can be heard to click as the engine speed increases slightly. The pump can be turned over by hand with the engine not running.

I took it back to the guy who refilled it (initially 950grammes), who removed it again, and put in 1500grammes, and the gauge showed no sign of over filling!!.

The air feels cool in the morning, but in the heat of the day, it can hardly be noticed.

Any more ideas?

TTFN

Glyn

[TimRdLotus]

Did the person evacuate the system with a vacuum pump for about 30 minutes before he refilled the system?

But it sounds to me like your compressor might be disengaging when you rev up the engine. The compressor should stay engaged until the pressure is either too high or low. If the compressor keeps cycling on and off, then you might a bad pressure switch which is located on the Receiver Dryer at the front of the vehicle. Also there should be a sight glass, see if there are bubbles.

the best way to ck the system is to hook up pressure guages and check your pressures. That will tell you if the system is working properly.

[glynherron]

Hi Tim,

The guy left it on vacuum for about 20 minutes.

I don't know if this is relevant, but while evacuating the R134a, a lot of oil came out like 200ml, which he thought was a lot.

He then put about 20ml back in before he refilled with gas.

On the question about the compressor disengaging, would freescan pick this up? I think I saw a screen which senses AC status, but I can't remember if its logged. My laptops at school so I can't check this today.

Is the receiever dryer at the front of the stack (front of car) or the back one, and what does the switch look like?

I have found the sight glass under the plastic ABS cover, I will check this for bubbles and report back.

I don't know if the guy who refilled mine just has the equipment or is also a specialist. What would I tell him to look for on the gauges for a correctly operating system?

Thanks and TTNF

Glyn

Did the person evacuate the system with a vacuum pump for about 30 minutes before he refilled the system?

But it sounds to me like your compressor might be disengaging when you rev up the engine. The compressor should stay engaged until the pressure is either too high or low.  If the compressor keeps cycling on and off, then you might a bad pressure switch which is located on the Receiver Dryer at the front of the vehicle. Also there should be a sight glass, see if there are bubbles.

the best way to ck the system is to hook up pressure guages and check your pressures.  That will tell you if the system is working properly.

<{POST_SNAPBACK}>

[rens914]

Hi guy's

don't know if the SE Turbo has a bigger compressor but i just filled mine by R12 (it's forbidden in the Netherlands so i had it done in belgium)

we have filled it up to 1,4 kg

it works super and freezes my knee of

perhaps you dont use the switches right

all the other switches eccept the fan must be switched off otherwise the system doesn't work

and with the motor running you should heare the magnetic click when the compressor turns on

[TimRdLotus]

The oil coming out is not a major problem since he added some back in.

But troubleshooting the ac is as follows:

1. Is the system charged? Assuming in your case yes.

2. Is the compressor engaging? You should be able to hear the compressor "click" on and off as you turn the ac switch on and off. If you don't then you got a power problem to the compressor.

3. Is the cooling fans on the radiators working?

3. If the above is ok, then you got a problem with the evap system of the ac unit. This is where the pressure check comes in.

I would check power to the compressor and for air bubbles on the sight glass. If the compressor is working and system full, the sight glass will be clear. If the system is low, then you'll see air bubbles.

Troubleshoot via internet is very difficult, go to a AC specialist and they should be able to track it down.

[Techspy]

One other possibility is that the flaps in the dash that determine weather you get outside air, cooled air or heated air, aren't working properly. They are vacuum activated. I couldn't get my heater to blow hot air. The vaccum line was disconnected so the flaps wouldn't move to the correct position. Give this a look.

[KVJ 786]

Hi Guys

Reading your notes on ac probs I am now joining you guys as I have also developed a problem on my S4S in Florida. Took my car out after a long time and found ac was not cooling, took it to a garage to check for freon and found ac belt chewed up. It was diagnosed that the compressor has ceased up according to the mechanic.

Question which bit ceases up? If the belt is not in place will I still be able to test and hear the clucth click as I turn on ac?

I think I also noticed the fans on the rad coming on, and the engine rpm increasing as normal.

Lastly how difficult to take out compressor from a MY 95 S4s? Where can I buy the correct belt in USA to match my broken one and can that be replaced while everything in place. ( ie Do I have to remove anything to that )

The other issue I have is heater has not worked for hot air, reading earlier someone mentioned that it is controlled by vaccuum. Is the vaccuum pump in the engine bay that controls the functions? If so then I have a prob cause the vaccuum is constantly running as though there is air getting into it. Something under my exhaust area is dissconnected, which I was told that is for hot/cold starting.

Any ideas would be greatly appreciated

Thanks

[fflyingdog]

The exhaust area problem is your EBV which if removed should have the pipe plugged(if not your vac pump will run continously),also your heater flaps/ventilation system is operated by your vac pump so if you have a leak or bad actuator will cause your vac pump to run ,pain to find but not that hard just a process of elimination.

Nick S4s

[AJay]

I am no expert however i have asked one and he says,

If the reciever Drier is not replace regularly (every four years i think), then the bags of silica that takes the water from the system can split, these will then flow round the system and could block the expansion valve and stop the system from working.

Everything else will look ok, ie correct amount of oil and gas... but the flow will be very poor.

It is located up under the passager foot well and is a pig to replace, (not too Expensive though).

[KVJ 786]

Hi Nick

Thanks for your idea on the vacuum line, I found the problem to be in the dash area. A thin pipe was completely off two ends which kind of puzzled to see where it went. Especially if you cannot see the damn valves clearly, but my wife got under both sides of front ( after removing seats ) and looked around and manage to locate the valve end and the t end to connect the pipe. Now air flow works OK and pump only cycles every few seconds, also have heat for a change working after 5 years LOL.

But the bad news is compressor has had it, Fitted belt and swirched on ac and wow had to turn off instantly as belt screemed when compressor clicked and energised but did not turn. Yet it turns freely with ac switched off.

Temp in Central Florida currently at 90 deg. so no driving Lotus for a while till ac fixed.

So ordered new compressor from JAE parts in California and waiting to receive in due course. At the same time going to replace ac drier unit and switch.

PS Is this compressor repairable like starters and alternators?

Thanks again Nick.

Ameer