There are a few reasons you can experience an under temperature fault on your Nordson ProBlue unit. Many people do not think about this particular cause discussed below.
ProBlue units circuity monitors the manifold temperature every 15 minutes after the "heaters" button is active. If the line voltage is low in your plant, the manifold may not reach the expected set temperature with in the 15 minute time frame set in the software. In this case, the unit will display a F2 fault.
There is a remedy for this situation. You can reprogram the unit to give the unit 30 minutes to heat instead of the default 15 minutes to heat.
One simple step on the circuit board will make this change:
Press and hold the "heaters" and "pump" buttons together while powering up the glue melter. During power up, the unit will display the code of Lo17O which indicates the 30 minute set time.
If you want to change the unit back to 15 minutes, repeat the process.