Hi,

Well here's the first idea to try.

Tape the thermostat probe directly to the heat tape in the middle shelf of the rack. It's best to do this in a place where the movement of the tub sliding in and out won't displace it - to one side or behind the tub works fine depending on how you built the rack.

The one that doesn't heat up at all sounds like a wiring issue though so try it in a different socket of the thermostat to rule that in or out if you can.

In a rack the top tubs will usualy be slightly warmer than the middle one with the thermostat probe and the lower tubs will be slightly cooler.

The difference is generally only a few degrees though.


dr del