I'm repairing a GBC 4250 laminator for a customer. When you turn the mach. on, the OK light comes on at the same time and the mach. doesn't heat up. Switch or main board? How do you repl. switch if bad. Been repairing all sorts of machines for 33 years, but this is a first. Any help would be greatly appreciated.

Eugene, September 2011

Probably a bad temp sensor. its located under the bottom heat roller center, held in place by 2 screws behind the lower spring loaded idler bar. the transistor fails open or the board comes unplugged and it can show ready when its stone cold. sensor part number is LM135h i think its available from digi key for about 12 bucks or you can order the board for about 200 bucks from GBC.

if you or anyone else have roll laminator troubles feel free to give me a call.

GBCs local first hour rate of $317.00 has been wonderful for my business

bob haller service and sales pittsburgh pa 412 366 4906, September 2011