CBMB MO GB SE

Trouble-shooting

Full heating power but no regulation

No heating

● Strap/short-circuit the terminals for the main sensor.

If this results in the heating now being turned off, then the fault is in the external sensor circuitry.

● Check that the airflow through the heater is sufficient. The airflow is insufficient if the yellow LED on the PCB is light up,

or the airflow might be sufficient but too turbulent for the electronics to be measured as sufficient, then the yellow LED

will sustain light up and there will be no heating.

The airflow sensor does need a couple of minutes of warm up time though, after the mains supply is switched on.

During this warm up time, the yellow LED will be light up, although the airflow through the heater is sufficient.

● Check that the sensor is of the correct type (TG-K310) and that its termination is made correctly.

● Check that the correct function for the Pulser or TTC is selected.

● Check the resistance of the sensor. Disconnect the sensor from the terminals before any measurements are taken.

The sensor for -20...+10°C (TG-K310) should have the resistance of 10k @ +10°C, 11k @ +4°C, 12k @ -2°C,

13k @ -8°C, 14k @ -14°C and 15k @ -20°C.

? ? ?

● Check whether or not the overheating cut-out, with manual reset, has been activated. If it has, then eliminate

the fault and reset it. Read furthermore the paragraph ”Overheating” at page 3.

● Check the overheating cut-outs and the heating elements by measurment.

● Check whether or not there is mains voltage at the heater terminal blocks. Check the interlocking devices, fuses,

breakers, etc.

● Disconnect the sensor from the terminals.

If the heater starts now, then the fault is in the external sensor circuitry. Otherwise, the fault is in the regulator

(Pulser/TTC).