22
5.1
D.H.W. PRODUCTION
The preparation of hot water is guaran-
teed by the glass enamelled tank unit with
magnesium anode for the protection of
the tank and inspection flange for its con-
trol and cleaning. The magnesium anode
must be checked annually and substituted
when it is worn. If the boiler does not pro-
duce hot water, make sure that the air has
been released by pressing on the manual
vents after having switched off the main
switch.
5.2
ADJUSTMENT
OF HEAT OUTPUT
FOR C.H. MODE
To adjust boiler heat output for heating pur-
poses, i.e., modifying the setting made at the
factory which is approximately 19 kW, use a
screwdriver to adjust the C.H. heat output
trimmer (1 fig. 21). To increase working
pressure, turn the trimmer clockwise; to
reduce pressure, turn the trimmer coun-
terclockwise. To facilitate the operations of
adjusting heat output, see the
pressure/heat output diagrams for natural
gas (methane) and butane or propane gas
(figg. 24/a - 24/b - 24/c).
5.2.1
Measuring gas
pressure at nozzles
To measure pressure at the nozzle, con-
nect the manometer as shown in figure 25.
This connection must also be used when
checking maximum and minimum gas pres-
sure; refer to the directions provided under
point 5.4.1 if you need to correct the set-
tings.
5.3
GAS VALVE
The boilers are equipped standard with the
SIT 845 SIMGA gas valve (fig. 26).
The gas valve is set at two pressure values:
maximum and minimum.
According to the type of gas burnt, these
correspond to the values given in
Table 4
.
The gas pressures at the maximum and
minimum values, are factory set. Conse-
quently they must not be altered.
Only when you switch the appliance from
one type of gas suppl y (me t hane) t o
another (butane or propane), it is permit-
ted to alter the operating pressure.
5.4
GAS CONVERSION
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 (fig.
27):
5
USE AND MAINTENANCE
11
10
9
8
7
6
5
4
3
2
1
8,1 (7.000) 11,6 (10.000)
17,4 (15.000)
23,2 (20.000)
POTENZA TERMICA/PUISSANCE CHAUFFAGE kW (kcal/h)
PRESSIONE UGELL
O /PUISS
AN
CE INJECTEUR mbar
29,0 (25.000)
12
W
ALL 25/60 - FORMEL 2560
FORMA
T/PL
ANET 25-30/60
25/60 C - OF (G20)
25/60 V - BF (G20)
13
25/60 C - OF (G25)
14
25/60 V - BF (G25)
30/60 BF (G20)
30/60 BF (G25)
15
Fig. 24/a
Pressure/heat output diagram for natural gas (methane)
20
15
10
5
8,1 (7.000) 11,6 (10.000)
17,4 (15.000)
23,2 (20.000)
POTENZA TERMICA/PUISSANCE CHAUFFAGE kW (kcal/h)
PRESSIONE UGELL
O/PUISS
AN
CE INJECTEUR mbar
25
30
0
29,0 (25.000)
W
ALL 25/60 - FORMEL 2560 - FORMA
T 25-30/60 - PL
ANET 25-30/60
25/60 C - OF
25/60 V - BF
30/60 BF
Pressure/heat output diagram for butane gas (G30)
Fig. 24/b
20
15
10
5
8,1 (7.000) 11,6 (10.000)
17,4 (15.000)
23,2 (20.000)
POTENZA TERMICA/PUISSANCE CHAUFFAGE kW (kcal/h)
PRESSIONE UGELL
O/PUISS
AN
CE INJECTEUR mbar
25
30
0
29,0 (25.000)
35
W
A
LL 25/60 - FORMEL 2560 - FORMA
T 25-30/60 - PL
ANET 25-30/60
25/60 C - OF
25/60 V - BF
30/60 BF
Pressure/heat output diagram for propane gas (G31)
Fig. 24/c
N
OZZLE
PRESSURE
mbar
HEAT OUTPUT kW (kcal/h)
N
OZZLE
PRESSURE
mbar
HEAT OUTPUT kW (kcal/h)
N
OZZLE
PRESSURE
mbar
HEAT OUTPUT kW (kcal/h)
4 W.M. (G20)
4 W.M.
4 W.M.
