Ariston UNO Installation Instructions Manual page 17

3.5 O
PERATIONAL
A
DJUSTMENTS
17
- Check the system pressure and, if it has dropped, open the filling loop
again to bring the pressure back up to 0.7 bar.
2. Check the exhaust flue for the fumes produced by combustion.
3. Make sure that all gate valves are open;
4. Turn on the gas cock and check the seals on the connections, including
the one for the burner, making sure that the meter does not signal the
passage of gas. Check the connections with a soap solution and
eliminate any leaks.
5. Turn and release the knob "C" to the RESET position for the lighting
system; the spark will light the main burner. If the burner does not light
the first time, repeat the procedure.
6. Check the minimum and maximum pressure values for the gas going to
the burner; adjust it if needed using the values indicated in the table in
section 4 (See the relative section for burner pressure adjustment within
the servicing manual).
(See section 3.2 for references) it is possible to:
- Set the temperature of the heating system by adjusting the knob "A"
- Set the temperature of the domestic hot water by turning knob "E"
To access the areas in which adjustments are made, it is necessary to open
the control panel, as indicated in section 3.3, then rotate the control panel
forward and remove the P.C.B. cover. Access is thereby provided to the
P.C.B. and to the following components:
1. the power supply cable connector;
2. the fuses;
3. Slow Ignition Adjustment and Maximum Heating Adjustment
Jumper "P" used to set the maximum heating adjustment and the slow
ignition adjustment is set to position "B" for normal operation.
To change the factory setting move the jumper "P" from postion ""B" to
postion "A". The red L.E.D. will begin flash. This indicates that it is now
possible to adjust the slow ignition and the maximum heating adjustment.
The slow ignition adjustment can be carried out by turning knob "E"
(D.H.W. temperature adjustment), the maximum heating adjustment can
be carried out by turning knob "A" (C.H. temperature adjustment)
To store the new settings, return jumper "P" to its original position "B".
During this operation the boiler must be powered at all times.
4. Setting the Ignition Delay
Jumper "N" controls the ignition delay and is factory set to 2 minutes
(position "B"). By moving the jumper to position "A" the ignition delay is
cancelled (0 minutes).