you need to check the compressor motor to see if its running, its down at the back outside (black pot).if it is not running you need to determine if its getting current or not, it is supplied via a thermostat or pcb, if you have a supply down at the compressor the problem is within the pot, there is a thermal overload cutout (toc) that may be blown or the whole unit may be fried, you need someone competent with a meter to check the electrics and compressor windings
keymatic
July 2012
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