Several years ago after it had lost its cool, I removed the cooling compressor (located under the port side settee on my B36/2002) and pipework to the inset into the galley worktop refrigerator. This also included removing the cooling plate within refrigerator and took it all to a firm of refrigeration engineers in Mochdre in North Wales. There they examined the system and found a small leak in the pipework where it had been rubbing or chafing against the woodwork of the port side settee. The pinhole in the tube was soldered over, the system was re-gassed and then returned and refitted onto the boat where it continued to work right up to when the boat was sold to its new owner. Where the pipework passed through the woodwork of the settee I made sure that it was protected by wrapping the pipe with polyurethane foam in order to prevent further chafing. So it could be worth looking to see that your system has not suffered a similar problem, and to provide suitable protection. The repair at the time cost about £170 including re-gassing the system.
