Nozzle Assembly; Combustion Head Setting - Riello RL 70 Installation, Use And Maintenance Instructions

D691
(A)
(C)
D694
(D)

COMBUSTION HEAD SETTING

(E)
Notches nr.
(F)
Light oil delivery
kg/h
Example with the RL 70 Model:
Boiler output = 635 kW - efficiency 90 %
Output required by the burner =
635 : 0,9 = 705 kW;
705 : 2
therefore, two equal, 60°, 12 bar nozzles are re-
quired:
1° = 7.0 GPH - 2° = 7.0 GPH,
or the following two different nozzles:
1° = 6.0 GPH - 2° = 8.0 GPH,
or:
D692
1° = 8.0 GPH - 2° = 6.0 GPH.

NOZZLE ASSEMBLY

At this stage of installation the burner is still dis-
(B)
assembled from the blast tube; it is therefore
possible to fit two nozzles with the box spanner
1)(A) (16 mm), after having removed the plastic
plugs 2)(A), fitting the spanner through the cen-
tral hole in the flame stability disk. Do not use any
sealing products such as gaskets, sealing com-
pound, or tape. Be careful to avoid damaging the
nozzle sealing seat. The nozzles must be
screwed into place tightly but not to the maxi-
D693
mum torque value provided by the wrench.
The nozzle for the 1st stage of operation is the
one lying beneath the firing electrodes Fig. (B).
Make sure that the electrodes are positioned as
shown in Figure (B).
Finally remount the burner 3)(C) to the slide bars
2) and slide it up to the flange 5), keeping it
slightly raised to prevent the flame stability disk
from pressing against the blast tube.
Tighten the screws 1) on the slide bars 2) and
screws 4) fixing the burner to the flange.
If it proves necessary to change a nozzle with the
burner already fitted to the boiler, proceed as
outlined below:
- Retract the burner on its slide bars as shown
in fig. (B)p.5.
- Remove the nuts 1)(D) and the disk 2).
- Use spanner 3)(D) to change the nozzles.
COMBUSTION HEAD SETTING
The setting of the combustion head depends ex-
clusively on the delivery of the burner in the 2nd
stage - in other words, the combined delivery of
the two nozzles selected on page 5.
Turn screw 4)(E) until the notch shown in dia-
gram (F) is level with the front surface of flange
5)(E).
Example:
The RL 70 Model with two 6.0 GPH nozzles and
12 bar pump pressure.
Find the delivery of the two 3.00 GPH nozzles in
table (D), page 5:
25.5 + 25.5 = 51 kg/h.
Diagram (F) indicates that for a delivery of 51 kg/
h the RL 70 Model requires the combustion head
D462
to be set to approx. three notches, as shown in
Figure (E).
D695
6
= 352 kW per nozzle;