7
10
9
6
7
6
+ H
TECNO 34-L
- H
Ø (mm)
(m)
8
10
+ 4.0
52
134
160
+ 3.0
46
119
160
+ 2.0
39
104
160
+ 1.0
33
89
160
+ 0.5
30
80
160
0
27
73
160
- 0.5
24
66
144
- 1.0
21
58
128
- 2.0
15
43
- 3.0
8
28
- 4.0
-
12
(A)
(B)
A
5
8
4
5
9
B
L (m)
TECNO 44-L
Ø (mm)
12
8
10
12
35
90
152
30
80
152
26
69
152
21
59
130
19
53
119
17
48
108
15
43
97
13
37
86
96
9
27
64
65
4
16
42
33
-
6
20
4
1
2
3
2
1
3
D3911
5
D3871
9
HYDRAULIC SYSTEM
FUEL SUPPLY
Double-pipe circuit (A)
The burner is equipped with a self-priming pump
which is capable of feeding itself within the limits
listed in the table at the side.
The tank higher than the burner A
The distance "P" must not exceed 10 meters in
order to avoid subjecting the pump's seal to
excessive strain; the distance "V" must not
exceed 4 meters in order to permit pump self-
priming even when the tank is almost com-
pletely empty.
The tank lower than the burner B
Pump depression values higher than 0.45 bar
(35 cm Hg) must not be exceeded because at
higher levels gas is released from the fuel, the
pump starts making noise and its working life-
span decreases.
It is good practice to ensure that the return and
suction lines enter the burner from the same
height; in this way it will be less probable that
the suction line fails to prime or stops priming.
The loop circuit
A loop circuit consists of a loop of piping depart-
ing from and returning to the tank with an auxil-
iary pump that circulates the fuel under
pressure. A branch connection from the loop
goes to feed the burner. This circuit is extremely
useful whenever the burner pump does not suc-
ceed in self-priming because the tank distance
and/or height difference are higher than the val-
ues listed in the table.
Key to lay-out (A)
H = Pump/Foot valve height difference
L = Piping length
Ø = Inside pipe diameter
1 = Burner
2 = Pump
3 = Filter
4 = Manual on/off valve
5 = Suction line
6 = Foot valve
7 = Rapid closing manual valve remote con-
trolled (only Italy)
8 = On/off solenoid valve (only Italy)
9 = Return line
10 = Check valve (only Italy)
HYDRAULIC CONNECTIONS (B)
The pumps are equipped with a by-pass that
connects return line with suction line. The
pumps are installed on the burner with the by-
pass closed by screw 6)(B)p.11.
It is therefore necessary to connect both hoses
to the pump.
The pump will break down immediately if it is run
with the return line closed and the by-pass
screw inserted.
Remove the plugs from the suction and return
connections of the pump.
Insert the hose connections with the supplied
seals into the connections and screw them
down.
Take care that the hoses are not stretched or
twisted during installation.
Pass the hoses through the holes on the left-
hand plate 5)(B), removing the thin diaphragm
that closes the two holes or as per the following
instructions: unscrew the screws 1), now divide
the insert piece into its two parts 2) and 3) and
remove the thin diaphragm blocking the two
passages 4).
Install the hoses where they cannot be stepped
on or come into contact with hot surfaces of the
boiler.
Now connect the other end of the hoses to the
supplied nipples, using two wrenches, one to
hold the nipple steady while using the other one
to turn the rotary union on the hose.