78
4.1
GAS VALVE (fig. 16)
The boiler is supplied as standard with a
gas valve, model SIT 822 NOVAMIX (fig. 16).
4.2
GAS CONVERSION (fig. 17)
This operation must be performed by
authorised personnel using original Sime
components.
To convert from natural gas to LPG or vice
versa, perform the following operations
– Close the gas cock.
– Replace the nozzle with OR (1) and gasket
(2) with the one supplied in the kit.
– Inspect all the gas connections using
soapy water or relevant products. Do not
use naked flames.
– Apply the nameplate with the new gas
flow layout.
– Calibrate the maximum and minimum
pressures of the gas valve following the
instructions provided in paragraph 4.2.2.
4.2.1
New fuel configuration
For access to the installer’s parameters,
press simultaneously keys
5
3
1
2
4
and
5
3
1
2
4
for
5 seconds (3 fig. 12).
The parameters will scroll up and down
with the keys
5
3
1
2
4
and
5
3
1
2
4
.
The display pane will show the values of the
parameter PAR 1.
If the boiler is a methane (G20) model,
SET
68
will be displayed.
To change the fuel to propane (G31), it is
necessary to set
SET 70
, by pressing the
key
5
3
1
2
4
.
The standard display will automatically
return after 10 seconds.
The table below shows the SET settings to
enter when the type of gas fuel is changed.
(*) In case of installation with polypropyle-
ne flue gas manifold with clapet valve.
4.2.2 Calibrating the gas valve
pressures
Measure the CO
2
values with a combustion
analyzer.
Sequence of operations:
1)
Press and hold the button down for a
few seconds
5
3
1
2
4
.
2)
Press the button for a few seconds
5
3
1
2
4
.
3)
Identify the CO
2
values at max. power by
adjusting the shutter (5 fig. 16):
4)
Press the button for a few seconds
5
3
1
2
4
.
5)
Identify the CO
2
values at min. power by
adjusting the OFF-SET regulation screw
(6 fig. 16):
6)
Press the buttons several times to
check the pressures
5
3
1
2
4
and
5
3
1
2
4
chan-
ge them if required.
7)
Press the button
5
3
1
2
4
once more to quit
the function.
4.4 DISASSEMBLING
THE SHELL (fig. 19)
To simplify maintenance operations on the
boiler, it is also possible to completely
remove the shell, as shown in figure 19.
Turn the control panel to move it forward
and be able to access the internal compo-
nents of the boiler.
EV1
EV2
1
2
5
6
Fig. 16
KEY
1 Upstream pressure intake
2 Downstream pressure intake
5 Shutter
6 OFF-SET
4
USE AND MAINTENANCE
MAX power
CO
2
(Methane)
CO
2
(Propane)
9,0 ±0,3
10,2 ±0,3
MIN power
CO
2
(Methane)
CO
2
(Propane)
9,0 ±0,3
10,2 ±0,3
2
1
Fig. 17
GAS
MODEL
PAR 1
Single (110 R ErP)
68
METHANE
(G20)
Sequence/cascade
69 (*)
Single (110 R ErP)
70
PROPANE
(G31)
Sequence/cascade
71 (*)
ATTENTION: Before performing any work on the boiler, make sure
that the same and its components have cooled in order to prevent
the risk of burns due to high temperatures.
