SUN G50 - G70
To perform a preliminary adjustment of head and air damper during installation (before commissioning
and consequently calibrating the appliance using instruments), use the graph below:
Heat
output
Model
Max
kW
GN4.10
388
GN4.11
452
GN4.12
516
GN4.13
600
GN4.14
695
Prextherm N 400
435
Prextherm N 500
541
Prextherm 550
598
Prextherm 620
674
Prextherm 800
870
Prextherm RSW 350
378
Prextherm RSW 399
432
Prextherm RSW 469
507
567,5
Prextherm RSW 525
648
Prextherm RSW 600
781
Prextherm RSW 720
Adjusting pump pressure
The pressure of the pump is factory-set to 12 bars, for optimum operation, and normally should not be
modified. Nonetheless, if under specific circumstances a different pressure needs to be set, once having
attached the pressure gauge and ignited the burner, use the adjustment screws "6" indicated in fig. 4.
In any case, it is recommended to keep within the range 10 - 14 bars.
3.2 Commissioning
Checks to be performed on first ignition, and after all maintenance operations that involve the discon-
nection of the appliance from systems or intervention on the safety devices or parts of the burner:
Before igniting the burner
• Check that the burner is correctly fastened to the boiler, and the preliminary adjustments described
previously have been performed.
• Make sure that boiler and the system have been filled with water or diathermic oil, that the valves in
the water circuit are open and that the flue gas exhaust pipe is free and correctly sized.
• Check that the boiler door is closed, so that the flame only propagates inside the combustion cham-
ber.
• Fit the pressure gauge and the vacuometer to the pump (removed before operation).
• Open the gate valves in the oil pipes, making sure that there is fuel in the tank and that the return
pipe is not blocked.
Attention: Blockages may cause the pump seal device to break.
GB
Nozzles
Burner
min
kW
1st stage
229
G50
4,5
266
G50
5
309
G50
6
352
G70
7
416
G70
8,5
279
G50
5,5
345
G50
7,5
359
G70
7
404
G70
8,5
522
G70
10
242,5
G50
4,5
277,5
G50
5
325
G50
6
364,5
G50
7,5
417
G70
8
502
G70
10
Cod. 35445644 - 08/2007 (Rev. 00)
Pump
pressure
2nd stage
bar
1st stage
3
12
3,5
14
4
13
5
12
5,5
12
3,5
12
4,5
11
5
12
5,5
12
7,5
12
3
12
3,5
12
12
4,5
5
11
5,5
11
7
11
Servomotor
L (mm)
air
EV
2nd stage
8°
10
15°
9°
12
15°
10°
15
20°
8°
12
15°
10°
15
15°
12°
18
15°
13°
23
15°
8°
12
15°
10°
15
15°
15°
25
20°
13°
15
20°
14°
17
20°
10°
20
15°
15°
25
15°
10°
14
15°
14°
22
20°
32
28
24
22
21
25
24
22
21
20
27
26
24
23
22
22
33