Specifications

CAREL gaSteam
43
11.3 Checking the Ionization Current
The burner safety consists of an electrode that uses the
actual flame of the burner as a current path to determine
whether or not the burner is lit. If the flame goes out the
circuit will be broken and the controller will shut the gas
valve to avoid fuel gas from being released. Verification
of this current of ionization can be performed by inserting
a meter capable of measuring µA (continuous current) in
series to the electrode flame. Faulty positioning of the
electrode could involve a reduction of the current of
ionization and cause the unit to shut down because it
interprets this as no flame. Correct operation can be
checked as below. Commonly the value of the current of
ionization is 5 µA for UG045, and 1.5 µA for UG090.
11.4 Replacing Components
11.4.1 Exchanger
To replace the exchanger, proceed as described in the proceeding description of maintaining the steam
generator.
To ensure the perfect seal of the various components, whenever performing any maintenance/replacement
operations involving the exchanger, always replace all of the related gaskets.
11.4.2 PTC Over-Temperature Sensor
The PTC sensor is located in the exhaust outlet, and does not require periodical maintenance.
If the sensor needs to be replaced due to a fault, proceed as follows:
• stop the humidifier by moving the ON/OFF switch to 0 and then checking that the display on controller
is off;
• loosen terminals 5T and 6T on the terminal block in the lower part of the electrical panel and the probe-
holder nut on the adapter joint and then remove the probe and the electrical cable.
Then replace the PTC probe by following the same procedure in reverse.
11.4.3 NTC Temperature Sensor
As in the case of the PTC sensor, the NTC water temperature sensor does not require periodical maintenance.
To replace the sensor, proceed as follows:
• stop the humidifier by moving the ON/OFF switch to 0 and then checking that the display on controller
is off;
• using the Velcro strip on the left-hand wall of the cylinder, open enough insulation to allow good
visibility of the NTC probe.
• use a special tool to remove the probe-holder split pin, and then remove the NTC probe from its
housing.
• Loosen terminals 3T and 4T on the terminal block in the lower part of the electrical panel and remove
the probe.
Then replace the NTC probe by following the same procedure in reverse.
11.4.4 Cooling Fan
The cooling fan starts when the machine is switched on, and is used to keep the operating temperature of the
electrical panel and the electronics within the designed limits.
If the fan is faulty:
• Disconnect the electrical connections;
• Replace the fan after having unscrewed the fastening screws.
Note: being thermally protected, the fan may switch off temporarily if it overheats, and then will start again after
having cooled down.
Burner Co ntrol
Module
Micro ammeter
10
mA
Min 1.5 uA