Hi guys,

It does sound like a leak. Not sure why my UV lamp showed up nothing. Do the guys at Shipston or any where else, off a service to find the leak for a fixed fee. Keep being charged £150 to allow them.to look for the leak, to be told no leak!!!!

Just ask them to fix the fault, or at least quote to fix the fault. Explain that you’ve had it recharged and no leak found, but the fault has reoccurred. Legally, an air con system should not be charged knowing that it may be leaking. The system should hold a nitrogen charge at MWP for a specific time prior to introducing refrigerant. The guys at Venture will know this.

geoffsnook wrote:

My car did that one side cold the other not my guy said the system works with just 50 grams but will not cool but will work and as soon as he found the leak fixed it and refilled it both sides were cold again in laymans terms there is pressure/gas but not enough to cool the complete system

Could there be a leak in the Evaporator which is located in the heater unit, which I assume is inside the car and which I also imagine would be difficult to access to locate a leak as there would be so much stuff around it, would probably need to remove some trim to get to it. Although if the leak was inside the car you might smell it as I assume the gas has a odour to it.

Cheers
Col

Yes, the evaporator is in the cabin, within the package that contains the heater core, air direction and mixer flaps etc, mounted under the dash. An electronic refrigerant sniffer will pick up a leak from a holed evaporator when poked into one of the outlet vents.
R134a (assuming a RRS2 uses R134a, could be the more modern R1234yf ???) does have an odour, but it’s quite faint.

Hope for the op's sake it's not that then, as that sounds like a lot of work and expense to replace it, hopefully would be under warranty though.


Cheers
Col

Hi guys,

So over the weekend I went all over every part of the air con system under bonnet I could get near, including removing the right air filter unit and use my new UV lamp. Not one drop of the. The type shows up a little at the charge points so it's got the in there.
So looks like no leak.
What I have found is a buliten on Topix for passager and drivers air vents at different temps. This is stepper motors not synchronised. Could be blowing half warm and cold at the same time???

Is there a way to see into the heater unit, just a little to look for any dye. Removing some trim is no problem.

Just looked Topix and it seems the heater motor is easy to remove. Lower passager trim out then un-bolt it. I would think with the motor out, the cores would be easy to see and UV show any leaks?

No access to view the evaporator, not without completely removing the whole heater assembly from the car, stripping it down on a bench and inspecting it.
The are two ways to determine if your air conditioning system is low on refrigerant charge. First is by by fitting a manifold gauge and making a judgement from the pressures seen with the system running, taking into account the ambient and cabin temperatures at the time of reading the pressures. A skill only a trained refrigeration engineer can successfully complete.
The second method is by weighing out the charge and comparing it with the specification. This method can be done with a modern charging machine, so doesn’t require the same training a refrigeration engineer has, only training for the operation of the machine required and therefore is the preferred route by many garage operators.
So... for example, if you car was recently correctly charged by weight to let’s say... 600 grams. Is now not cooling efficiently and the system was weighed out with only 450 grams recovered, then you have a very small leak.
If the system is recovered and the weight of refrigerant removed is what is specified for your car, then the problem lies elsewhere.
My advice would be, take your car to a garage that has a good air conditioning repair reputation and ask them to weigh out what is in the system. The result will rule out or confirm if you have a leak. Then you can move on to determine other problems. Make sure the garage doesn’t just go ahead with a ‘recharge’. Ask them specifically to do a step by step diagnosis. Firstly, informing you how much refrigerant has been recovered BEFORE doing anything further.

There are no air conditioning people in the west Midlands, that's the issue. The main dealer has stated no leak, the local supposed air con experts state no leak. Both added dye, both done pressure tests. I have checked all under bonnet and no dye, not even a mark. I will remover motor in next couple of days. I would guess that if dye is leaking in the heater unit, the airflow would splash it around so should be something but costs nothing to check.

If there is no leak and the correct charge remains in the system, assuming obvious things like you have a clear pollen filter, the heater blower fan is working ok etc etc then your problem could either be a sticking air mix flap motor on the side which isn’t cooling very well, effectively mixing warm air with the cold air you expect to feel from the vents OR you have a worn compressor which isn’t pumping efficiently. A worn compressor can give the same symptoms as a system low on gas, hence why it’s important to rule out a leak first by weighing out as suggested. A worn compressor is determined using a manifold gauge.
Inside a compressor is a ‘ring’ of pistons, each acting on a swash plate with a reed valve at the head of each cylinder. If one of those reed valves is cracked, the compressor will still pump but not to it’s full efficiency. If this is the case, a new compressor is required, they can’t be rebuilt.

Looking at Topix, if the dealer do the tests as instructed, they should run the car with high and low pressures measured etc so should show compressor issues. Pollen filters done a month or so ago at service.
There is a buliten on Topix describing the same issue and down to stepper motors not synced so this would cause the issue too

Why not simply check to see if the HVAC Control Module software has been updated, if not have it done. If still no different have the stepper motors, flap actuators etc. calibrated which should then eliminate that side of it, if that all checks out o.k. and if still no different then start to look elsewhere. You have already been told twice there is no leak found, could have it checked and re-gassed as many times as you like it will not cure it if there is no leak, surely you need to check everything that can influence it, not just some of it. Have you tried a thermometer in the vent which is blowing cold and see what it pulls down to, which I imagine should be in the region of 5 or 6 degrees not sure on that though, it should however actualy be checked through the center air vent I believe. If It doesn't that may point to the A/C side, if it does then that could point to the ventilation and air distribution side.


Cheers
Col