Gas Valve Adjustment - Baxi LUNA HT 1.850 Installers And Users Instructions

Carry out the following ope rations in the given sequence:
1) Calibration of the maximum heat output. Check that the CO
heat output, is the same as that shown in table 1. Otherwise, turn the regulation screw (V) on the gas valve. Turn the screw
clockwise to reduce the concentration of CO
2) Calibration of reduced heat output. Check that the CO
heat output, is the same as that shown in table 1. Otherwise, turn the offset regulation screw (K) on the gas valve. Turn the
screw clockwise to decrease the concentration of CO
Pi: Gas supply pressure connection
point
Pl: Air signal input from fan
V: Gas flow adjuster screw
K: OFFSET adjuster screw
Caution: in the event of the boiler failing to ignite, or when replacing the gas valve, the recommended procedure is
to tighten the adjuster screw (V) fully and then back off 2 1/2 turns, repeating the steps described above.
IMPORTANT:
If the appliance is being converted from natural gas to propane (LPG), the following operations must
be performed before calibrating the gas valve as instructed above.
• Replace the gas nozzle placed inside the gas valve (flow gas connection).
To perform this operation it is necessary to remove the gas valve by undoing the inlet and outlet connections and un-
screw the nozzle using round-nose pliers.
Check the seal of the gas couplings removed beforehand.
• On the control panel display set ignition power parameters H536 - H541 - H608 - H609 - H610 - H611 - H612 and H613.
The values to be input and the diagram to use are given in table 2 or 2.1. The programming methods are described in
chapter 15.
To simplify calibration of the gas valve, the "calibration function" can be set directly on the boiler control panel by pro-
ceeding as follows:
1) Press the keys (2-3) together until the display shows the pointer " " alongside the
2) Press the keys to set the fan speed at the minimum and maximum heat output (%PWM);
NOTE -
to set the minimum and maximum heat output quickly, press the
3) press either of the two
INSTRUCTIONS PERTAINING TO THE INSTALLER

14. GAS VALVE ADJUSTMENT

2
and anticlockwise to increase it.
2
measured on the flue, with the boiler operating at the minimum
2
and anticlockwise to increase it.
2
keys to exit the function.
28
measured on the flue, with the boiler operating at the maximum
GAS NOZZLE
V
Figure 13
Pl
K
Pi
symbol (about 6 seconds).
keys respectively;
910.024.1 - EN (AUS)