Aircon Yet Again

[mikej]

Hi all i have a fully functioning air con system which works as it should with no flashing panel etc apart from the fact that it just is not cold enough , its cool but not cold as it should be . It has been regassed 3 times in two years to try and get to the bottom of it and each time no leak has been detected the compressor kicks in and out as it should and i have used it for hours on end but it just ain't bloody cold enough each time its regassed to the required quantity of gas but cannot reach the required temp , has anyone experienced this or have any suggestions please??????

mike.....

[chromedome]

Comparing my climate control a/c to a manual version, like in my son's Picasso, I find the cooling effect to be more "subtle" but still cools the car ok.

 

Have you tried manually setting the temperature to 18C and putting the fans on full. I think you are looking to get around 4C at the vents.

Edited May 13, 2008 by chromedome

[mikej]

Just had a quick look under the bonnet at the AC sticker and it states Charge Level , Evaporator is

 

1 700 + 50g

2 1050 + 50g

 

What is the correct amount of Refrigerant that should be put into the system is it 700 + 50g or is it 1050 + 50g although unlikely maybe these garages are not putting the correct amount in to start . I believe i have climate control , i deffo have dual front and rear controls or another blower in the rear but was under the impression that this was just to recirculate the already cooled air to the rear not actually rear aircon ? . Can someone advise on the correct amount of R134a refrigerant that should be going in and what would be a realistic % quantity left in the system say a week after a refill .

thanks again , determined to get to the bottom of this once and for all.

mike.....

[chromedome]

Sounds like you have single a/c, therefore option 1 700 + 50g.

[marinabrid]

i had this problem last year , the dryer unit may need changing, it worked wonders for me. the fitter said that they were supposed to be swopped every 2 years. i believe this could be argued though after reading some threads. they are around

[mikej]

Quote ( Sounds like you have single a/c, therefore option 1 700 + 50g. )

 

This is a little confusing as there are additional aircon pipes running to the rear beneath the car and as already mentioned i have dual controls 2x individual fan & temp controls for front and rear from the same climate control unit thats fitted beneath the stereo so i would have opted for the higher figure of 1050 + 50g but its not the first time i have been wrong ??, i mentioned that i believe the rear was just to circulate the already cooled air this is something i read on this forum and might not actually be the case , if anyone knows different then please shout

[sparky Paul]

If you look under the bonnet, two aircon pipes come from the back of the front evaporator and through the bulkhead. On a single aircon vehicle, these two pipes then head towards the offside of the bulkhead before disappearing down and towards the front of the car.

 

If you have an additional two pipes which join these near where they pass through the bulkhead, heading down and underneath the car towards the back, you have twin aircon - i.e. an additional evaporator at the back of the car. I believe the cars with twin aircon also have roof vents for the cooled air.

 

The fill quantities 1: 700g+50g and 2: 1050g+50g refer to the number of evaporators fitted, 1 or 2.

 

Sounds like you have two evaporators, so 1050g would be correct.

[MrT]

On the MK2 if you have two evaporators you will have air outlet vents in the roof above the second (3 outlets) and third (2 outlets) row seats, a really thick rear left pillar against the hatch (for the air pipes) and normally no sunroof and a non-opening very rear left window.

 

Another point I have noticed is that in very hot weather 25+ at idle there may not be enough speed on the compressor to get maximum cooling, once you are get a few revs there is a good increase in cooling power. This will vary according to the type of engine and compressor across the models. On mine at idle (about 600rpm) with maximum cooling front and rear, the incoming air is around 48F at idle and 40F at 2000rpm+ (6250rpm is max).

[mikej]

Well i havn't got a single roof vent anywhere and all my windows including the rears open so maybe the rear blower is just to circulate the already cooled ( or not in my case ) air around the car after all , why would the bloody controls for the rear include a temperature adjustment then ? don't make much sense to me !

[widu13]

It's for the rear heater matey. In summer it just helps push the conditioned air around.

[DaveM]

You'll also find the 'dual climate control' temperature for the rear cannot be set lower than the front (I think it might let you select 1 degree lower, but that's it)

 

If you have no ceiling vents, you only have single air con.

 

I made the mistake of believing I had dual air con so charged the system to the upper figure which screwed up the whole system !

 

looking at a compressor change now, but not sure if the over charge was the cause of the failure

[big_kev]

Quote ( Sounds like you have single a/c, therefore option 1 700 + 50g. )

 

This is a little confusing as there are additional aircon pipes running to the rear beneath the car

 

You will find that these are water pipes for the hot water from the engine to get to the rear heater.

[mikej]

QUOTE 1,I made the mistake of believing I had dual air con so charged the system to the upper figure which screwed up the whole system !

 

2,You will find that these are water pipes for the hot water from the engine to get to the rear heater

 

 

Oh sh1t ! i'm pretty sure on the last few recharges the garages have charged at the upper figure so maybe my system is now stuffed as well , what problems if any did you have before and after the recharge and did your new compressor sort your issues out ? Didn't know i had a rear heater so you live and learn , thanks all for the input people , the quest i feel continues . Having only experienced non ford aircon my wife pug 307 which was very cold maybe i need to sit in another working galaxy to get an idea of just what i should be getting as i have said the system is working as it should apart from the fact it just ain't cold enough its cold but not cold enough !

[MrT]

Normally on an overcharge your pressure goes way to high and the overpressure switch (same switch as low pressure) will trigger and cut out the air-con and you will get the flashing display on the climate control and lack of aircon, just as you would with low pressure. If the overpressure switch fails, it could be expensive.

[mikej]

QUOTE Normally on an overcharge your pressure goes way to high and the overpressure switch (same switch as low pressure) will trigger and cut out the air-con and you will get the flashing display on the climate control and lack of aircon, just as you would with low pressure. If the overpressure switch fails, it could be expensive.

 

????? Well my display has not flashed and the aircon has always worked although not cold enough so god knows whats going on ??????

[daran71]

If the overcharge hasnt triggered the HP (high pressure) switch to trip then the system still wont work properly even if its still running and that may be your problem. The other thing to check is the condensor (like the radiator to get rid of the heat) it needs to be clean through the fins to ensure maximum efficiency.

 

I would see if you can get someone who knows what they are doing to do the following-

 

1 - Reclaim the gas out of the system

2 - Nitrogen pressure test the whole system for leaks

3 - Evacuate the system usng a vac pump for a couple of hours to make sure there is no moisture in the system

4 - Use the nitrogen to blow the condensor clean

5 - Recharge system to the correct levels

6 - Warm the car up with the heaters

7 - Switch on a/c and use the refrigeration guages to check the pressures in the system - a good engineer could actually charge the system without knowing the correct charge and just feather refrigerant in until the pressures were correct!!!

8 - Check the temperature at the vents is correct

 

Hope this helps - spent many a day going through this method on cars and unless there is a major part failed it should sort you out!!!

[MrT]

if you have not already done it, by an air con thermometer from Halfords or similar for under

[mikej]

Wow a lot of good advice coming through , thanks everyone i will firstly go and try to purchase a thermometer to test the actual temp from the vents . If anyone has any tips on how best to do this , what to set the climate to etc please feel free to shout .

thanks again

mike ........ :)

[MrT]

Somewhere on this site someone a year or so ago posted the information from the Ford TIS on how to do this. It includes the graph of what the outlet temperatures should be compared to the outside temperature. If you spend a bit of time searching this technical section you should find it.

[mikej]

Ok managed to get a thermometer from halfrauds and after 40 mins of driving on motorway the centre vent temp was bang on 40 degrees Farenheit and wouldn't budge under that , that was with the aircon set to coldest setting with front and rear blowers going full chat and only the central vents open . The temp inside the car on the climate control was showing 19 degrees centigrade which i think is 66 degrees Farenheit , while in Halfrauds i purchased a can of R-134a refridgerant this came with a gauge for measuring the system pressure , when i fitted the gauge it gave an alert reading of 45-65psi ( DO NOT ADD REFRIGERANT SEEK PROFFESIONAL HELP) apparently it should read 25-45 psi so it could have been overcharged by quickfit DO THESE TEMP FIGURES MAKE ANY SENSE TO ANYONE ? Also found the graph from a previous posting but this i think shows outside temp against vent temp unless i am mistaken and i ain't got a clue how cold it is today lol..

 

Think i am about to loose it anytime now .........

[seatkid]

40 deg F = 5 deg C. Its working fine! (much lower and the evaporator would ice up)

 

You probably put the gauge on the high pressure port - the one near the radiator/condensor. Its supposed to go on the low pressure port - on a Mk1 its hidden behind the offside indicator, don't know where it is on the MK2

 

You either have overly high expectations or maybe your pollen filter is blocked leading to low air flow. Best temperature lowering is acheived by setting the CC to vents only and recirc.

[mikej]

Quote 40 deg F = 5 deg C. Its working fine! :)

 

Please don't tell me that now , just been in the wifes 7 year old pug 306 never ever been regassed since new , put thermometer in center vent and got 32 degrees farenheit ? Is the aircon on the Galaxy really so crap ????????

[MrT]

When you fill and measure the low pressure you are meant to have the air con running, if it is not, the low pressure reading will actually be higher than it should be. Also I have the same guage and when my car had just been correctly filled the pressure reading was just over where it should be. The gauge does not make good contact with the valve in the low pressure connector and I have to push the gauge connector hard down to get the pressure to read correctly. I don't trust the gauges accuracy at all but as it is consistant I can tell if the pressure has dropped.

[mikej]

You probably put the gauge on the high pressure port - the one near the radiator/condensor. Its supposed to go on the low pressure port - on a Mk1 its hidden behind the offside indicator, don't know where it is on the MK2

 

No not possible both ports in front of engine bay and the gauge only fits on the low pressure one , the wifes car is definately colder just double checked and the temp dropped straight to 35 degrees F sorry not 32 , my eyes were bloody watering trying to read the gauge maybe like you say i'm expecting too much from it , it is after all a larger cabin to cool . Can the pollen filter affect the temp i havn't changed it for two years ???????

what are others able to get at the center vents i wonder as many have said their aircon is freezing , i say many but it may be the few were the system is still working lol..... :)

[mikej]

When you fill and measure the low pressure you are meant to have the air con running, if it is not, the low pressure reading will actually be higher than it should be. Also I have the same guage and when my car had just been correctly filled the pressure reading was just over where it should be. The gauge does not make good contact with the valve in the low pressure connector and I have to push the gauge connector hard down to get the pressure to read correctly. I don't trust the gauges accuracy at all but as it is consistant I can tell if the pressure has dropped.

 

Yeh i had the car running at fast idle for about five mins and this is after leaving the motorway and without switching the engine off , had no issues fitting the gauge , pressure was constant and the wifes car was well within the claimed safe zone on the gauge ???? i give up. :)