Riello DB 16 SM C01 TC A0 FS1 T250 Installation, Use And Maintenance Instructions page 37

6
Maintenance
6.1 Photocell disassembly and maintenance
The photocell is fixed to the burner by a bayonet connection.
If it needs removing for cleaning, it should be turned by 1/8 in an anti-
clockwise direction and then removed.
Working with pre-heated combustive air.
Sensitive element disassembly
If the sensitive element in the photocell needs replacing, proceed as
follows:
1 Remove the four fixing screws from the rear cover and then re-
move the cover.
2 Remove the sensitive element support.
3 Remove the sensitive element from the fixing plate.
4 Install a new element on the plate, avoiding direct contact with the
hands.
5 Refit the sensitive element support and the photocell cover.
6.2 Checking the flame detector
UV cell
Minimum current for correct working is 70 µA.
If the value is lower, it could be due to:
• exhausted photocell;
• low current (lower than 187 V);
• bad regulation of the burner.
In order to measure the current, use a microammeter of 100 A c.c., connected in series to the photocell, as in the scheme, with
a capacitor of 100 F - 1V c.c. at the same level of the instrument.
6.3 Periodic checks
We recommend carrying out the following checks:
LIST OF MONTHLY CHECKS
1 Inspect the flame detection device and check it is undamaged and clean.
2 Check the ignition device and clean if necessary.
3 Check the right pressure levels for fuel and air.
4 Check the correct movement and setting of the air damper and relative lifting assemblies.
5 Check the start up sequence and the safety interlocks, by simulating the relative anomaly situation.
LIST OF YEARLY CHECKS
1 Check the fuel blocking valves are still well sealed.
2 Check the settings on the pressure switches.
3 Visual check of the wires and connectors.
4 Check and clean the pressure test points.
5 Check the installation pipes for leaks.
6 Visual check of any damage and/or deformation of the following components:
- cylinder/distributor unit;
- flame disc;
- ignition unit;
- flame pipes.
D2143
Extraction
Fig. 28
Fig. 26
Cooling air
attachment (Rp 1/4)
P max. 50 mbar
Fig. 27
Assembly
D1143
17
D2142