3M 9209 is our most popular 3M repair kit. We recommend that if you have 2-5 PG II glue guns operational keep one repair kit on hand, 6-15 PG II glue guns it’s nice to have two 9209, 16-20 glue guns in use best to have 3 of the thermostat TCO repair kits.
Make sure your PG II pneumatic glue gun is disconnected from electrical and compressed air service. Remove the 3 screws from the heat shield. The thermostat and TCO are assembled as a unit you need to replace the entire old unit, regardless of which piece has failed. Remove the Quick-Slide clips from the current thermostat. Then remove the two screws holing the thermostat in place and pry the thermostat from the block. Next simply insert your new thermostat. Make sure the rear rim of the thermostat has been slipped into the slot in the heat block before affixing the screws. The thermostat cutout assembly is removed by unscrewing the Phillips screw that holds the thermal cutout to the head block on the stand off strips. Remove the other end of the thermal cutout from the terminal strip with a small Phillips screwdriver. Naturally the procedure is reversed when replacing the thermal cutout.