Sorry for the long delay in post but I have been very busy.. By April I will be fully off grid solar powered for Electricity and  Today I will start to integrate the good bits of my my 20 year  old Fridge Freezer into my 1 year old Laser cutter ready for full scale Production in April if all goes well fingers crossed.. .. Reason the laser cutter needs to have its coolant kept below 20C Currently even with a CW3000 Industrial Laser chiller Im limited to 2-3 hours of Laser cutting this is ok for R&D work depending on my coolant start temperature which is about 8-10C. As I discovered last year Ambient temperate soon creeps up and reduces my lasering time considerably.  It took me 2-3 hours of careful destructive disassembly to recover the whole freezer refrigerant system in tact still full of its refrigerant gas.
You ask why dose a 60W laser need so much cooling!! Well the laser tube is only 15% efficient so there is about 300W of waste heat to get rid of. The American RF Lasers are built into a huge lump of Aluminium the 50W one I had on loan was set in 25+ kilos of Aluminium this is then cooled by a stack of cooling fans take a look at the FabLab 30W laser it has a full row of fans on the top and bottom and back of the machine. Pictures of my Laser cutter the mods to follow...