PeachParts Mercedes-Benz Forum - View Single Post - Thinking of buying a new a/c compressor "kit"

Graham · #40 06-24-2010, 10:36 AM

Just another piece of information re the hydrocarbon based refrigerants.

I have an '85 300D that was converted to R134a when the original R-12 compressor failed. The replacement compressor failed the next year. It was replaced under warranty with a rebuilt and that unit lasted for about 4 years. It eventually seized and I gave up on A/C because we no longer used that car for long trips.

But, my wife drives the car and has been complaining about lack of A/C. So, I took it into a local A/C expert. This is the best A/C shop in our area and even the MB dealer uses them. They SUGGESTED I switch to a hydrocarbon based refrigerant. I asked why and they gave several reasons. Main one being that the 300d's R-12 system was not designed for the higher R134a pressures which just puts a strain on old parts making them more likely to leak. Second reason, was a legal one in Canada which requires them to completely evacuate a system that is even suspected of leaking IF it has R-12 or R134a. But this is not the case if it has HC. In latter case, it is permissible to just top up from time to time.

I asked them about contamination of their equipment etc. They said it was not a problem because they tested refrigerants to find out what they were and had equipment to recover all types. Only concern they had was if stop-leak additives were presnt because they clogged their recovery systems.

In Canada it is not legal to buy or use R-12. Nor can we buy R134a retail (unless we visit USA!). Only DIY refrigerant sold (and it is quite common), is hydrocarbon based (several makes). Major chains like Canadian Tire sell it and install it.

I have not gone ahead with A/C for 300D. They wanted $1200 for complete job of which $500 was a NEW compressor (but still of Chinese manufacture). 1 year warranty.

I don't really know what I will do. Maybe look for a junkyard compressor and install it myself either with R134a or HC. (I bought some R134a for my E-Class, but no leaks since condenser was replaced)