Check Ionisation Current; Flue Gas Temperature Sensor; Water Temperature Sensor; Fuses - Carel gaSteam UG045 05 Serie Manual De Servicio

2.2

Check ionisation current

Ionisation current is checked by placing a microammeter set to 10 μA full scale (direct current) in series with the fl ame detection
electrode. Incorrect positioning of the electrode may lead to a decrease in the ionisation current and burner shutdown due to
incorrect fl ame detection. In this case, check the correct position and condition of the electrode, its electrical connections, and
the earth connection of the burner. The ionisation current is normally 5 μA.
1
2.3

Flue gas temperature sensor

The fl ue gas temperature sensor is located in the fl ue and does not require periodical maintenance. If the sensor needs to be
replaced due to a fault, proceed as follows:
• stop the humidifi er by turning the switch to 0 (OFF) and checking that the display is off ;
• open the electrical compartment to access the panel;
• loosen terminals 10T and 11T (or 10Z and 11Z, see the wiring diagram) on the terminal block in the bottom of the electrical
panel and the probe holder nut on the adapter joint and remove the probe and the cable.
Then replace the sensor by following the same procedure in reverse.
2.4

Water temperature sensor

This does not require periodical maintenance.
To replace the sensor, proceed as follows:
• stop the humidifi er by turning the switch to 0 (OFF) and checking that the display is off ;
• open the panels to access the water circuit (Fig. 1.a);
• remove the sensor from the stainless steel housing in the level sensor support at the front;
• loosen terminals 12T and 13T (see the wiring diagram) on the terminal block at the bottom and remove the probe.
Then replace the sensor by following the same procedure in reverse.
2.5

Fuses

Fuses 1, 2, 3 measure 10.3x38 mm and are contained inside the fuse carrier; while fuse 4 measures 6.3x20 mm; to check the fuses,
test continuity using a tester. Use fuses with the ratings indicated in the table:
Models
fuses 1 and 2
fuse 3
fuse 4
2.6

Cooling fan

The cooling fan starts when the unit is switched on, and is used to keep the operating temperature of the electrical panel and
the electronics within the design limits. If the fan is faulty, after having removed panel B (Fig. 1.a):
• detach the electrical connections;
• replace the fan after having unscrewed the fastening screws;
Notice: being thermally protected, the fan may switch off temporarily if it overheats, and then will start again after having
cooled down.
Notice: If replacing the burner or one of its parts, the fl ue gas calibration procedure needs to be repeated (see the Instal-
lation, commissioning and user manual).
Notice: If the electronic controller is replaced, the correct unit model needs to be confi gured by following the guided
commissioning procedure (the unit model is shown on the rating plate inside the humidifi er).
gaSteam +0300123ML rel. 1.0 - 03.12.2021
Min 0,9 μA
UG045 UG090
2
Key:
1 microammeter with 10 μA full scale
2 test equipment
Fig. 1.b
UG150 UG180
2 A T
1 A F
3.15 A T
ENG
UG300 UG450
3 A T
Tab. 2.h
17