[Wendymott]

In the 80's our company was requested to look at the problem of Beer Cooler compressor motors killing the relay switch module. The Peak voltage was horrendous as the contacts opened, killing the relay drive transistor, thus keeping the relay on, thus the Ice bank becoming solid ice.
We had little room to fit an R/C snubber circuit, thus we bought many 1000 VDR's (voltage dependant resistors)... I cannot remember the value at which they conducted, but Farnells were well happy. We drilled two holes one either side of the relay/ motor contacts.
As I say we retro fitted many 1000, NO returns... Eventually IMI paxman who made the coolers, had them fitted at source.
The hardest part of the whole operation was removing the pcb that was mounted in a tight fitting plastic case, a lot of sealant was used in some versions, and none in others..
I seem to remember the VDR's were rated at 300/400V.... but as I say.. its a long time ago.