When's A Service Plan Not A Service Plan?

[wass]

Regards the re-gassing of the aircon I can't find anywhere whether this should be covered under warranty. Actually I can't find detailed info. as to what the warranty does cover. Can someone help me out on this?

Air conditioning work has in the most part , been misunderstood for years.The gas part of the air conditioning system also contains the oil and as such is totally sealed. Regassing or replenishment of air contditioning oil is only necessary when a component has failed. The component which has failed may be as small as a seal but never the less, it has failed and should be covered by waranty,however, many in the auto industry like to promote the idea that all airconditioning systems leak and as such, air conditioning regasses are a matter of course and are therefore not covered by warranty.

The concept of an air conditioning system having an acceptable amount of routine leakage flies in the face of F gas regulations.

In the case of R134A refrigerant, which a lot of air conditioning systems use, more or less ensures that the system will cease to function if it has the slightest of leaks. R134A is a refrigerant which is made up of a mixture of various compounds of gases;some components of the mixture have an extremely small molecular size which enables those elements to leave the system through the smallest of apertures whilst leaving the larger molecular size of components in the system. In this way, a minute pressure drop will be observed ,however the refrigerant gas remaining in the system will be all but useless. Pressure testing the system with nitrogen fails to reveal the leak simply because nitrogen has a larger molecular size than he component of R134A which has leaked.

If you follow this line of argument, you can see that to the non specialist observer, it would appear that there isnt a system leak and therefore one would conclude that the refrigerant has 'worn out' and requires replacement as a matter of routine.

I found out about this issue some years ago from the manufacturer of catering refrigerators. They has an issue with porus refrigerator coils. Having pressure tested the coils successfully, they would build the coils into a refrigerator and test run the unit over some months only to find that the performance of the unit would gradually deteriorate. Subsequent pressure testing of the coils would reveal no problems at all, however, when, oout of desparation they immersed the coils in water and pressure tested with R134A they discovered a mist of small refrigerant bubbles rising from the solid copper coils. Respecifying the refrigerator coil construction solved the problem in one and brought to an end a complete mystery. The same mystery still exists in the motor industry to the extent that many garages and indeed manufacturers look upon refrigerant as they would look upon the air in the tyres. They will not accept that refrigerant fails to be effective due to one fault and one fault only and that fault is a leak.

[Opifex]

That's very interesting and informative,Wass.

Thanks for posting.

[stompe]

Thanks Wass, i found it interesting too.

[monya]

Yep, I reckon I was had. I had to argue to get the brake fluid changed FOC as well. I think these service plans are a con. The only advantage would be if fixed service costs rise during the plan lifetime. There is too much left out of these plans eg de dusting brake pads. Greasing locks and catches. Seems common sense in a service. Next time around any 'extras' they come up with I'll ignore and if something fails as a result they can fix it under warranty. If they argue that a problem is due to lack of maintainance I'll refer them back to the service plan and suggest it should have been included.