xmexclusive wrote:Never sectioned one but rumor has it that the dryer contains silica gel and when it gets saturated the containing bag bursts and the resultant mess gets spread all round the system. This then overloads the compressor and burns it out. Chances are the system is then inadequately flushed and the residual debris slowly works round the system then takes out the replacement compressor the day after the warranty ends. All crap spread by aircon specialist to fleece you or is it?
The exact composition of chemicals and the construction does as far as I can see vary from manufacture to manufacture and range to range, however from such X section drawings I have seen there is no way they will burst and contaminate the system.
R 134 systems will self contaminate and destruct if they get contaminated by moisture which can happen during charging and maintenance if adequate care is not taken and from observation and conversation I am sure that many mechanics who work car aircon systems do not really appreciate just how clean and how much attention to detail is required.
E.G you cannot afford to leave any pipe open for more than a few seconds, if the system is broken down and is going to be left like that for a while each section really needs to be capped and charged with dry nitrogen. If the lines to the compressor are left open for more than about fifteen minutes the oil will have absorbed more moisture than is good for the system and because of the tight molecular bonding between the oil and water the dryer will only get some of it out. Result the whole lot slowly turns acidic and starts rotting from the inside out.