13
Type of boiler Combustion gas pipe
dimensions (mm)
Flue gases
pipe
(methane gas) (m)
RTT 930
350
69.14
99.56
If the fuel is methane gas:
Type of
boiler
(*) Cross-section of the
opening for natural ven-
tilation (cm²)
(**) Volume of air
required for forced
ventilation
***
Lower part
Upper
part
Lower
part
Upper
part
RTT 378
1,971
985
1,224
816
RTT 448
2,285
1,142
1,450
967
RTT 506
2,546
1,273
1,639
1,093
RTT 564
2,808
1,404
1,827
1,218
RTT 610
3,017
1,509
1,978
1,319
RTT 663
3,253
1,626
2,147
1,432
RTT 715
3,488
1,744
2,317
1,545
RTT 773
3,750
1,875
2,505
1,670
RTT 831
4,011
2,006
2,694
1,796
RTT 878
4,221
2,110
2,844
1,896
RTT 930
4,456
2,228
3,014
2,009
(*) If natural ventilation is used.
(**) If forced ventilation is used.
(***) The value in the “Lower” column refers to the clean air in-
put, the one in the “Upper” column to the air output.
To ensure the boiler is operating at optimal conditions, the tem-
perature difference between the supply water and the return
water should be no greater than 20 °C. The boiler should not be
started or run with water volumes lower than those indicated in
the following table.
Type of
boiler
Output
∆
t = 15 K (*)
∆
t = 20 K (*)
kCal/h
kW
Water
flow
rate
Water
resist-
ance
Water
flow
rate
Water
resist-
ance
m
3
/h
mbar
m
3
/h
mbar
RTT 378
325,000
377.9
21.67
102
16.25
54
RTT 448
385,000
447.7
25.67
147
19.25
80
RTT 506
435,000 505.8
29.00
180
21.75
105
RTT 564
485,000 564.0
32.33
160
24.25
78
RTT 610
525,000 610.5
35.00
175
26.25
88
RTT 663
570,000 662.8
38.00
200
28.50
115
RTT 715
615,000
715.1
41.00
220
30.75
130
RTT 773
665,000 773.3
44.33
160
33.25
85
RTT 831
715,000
831.4
47.67
180
35.75
90
RTT 878
755,000
877.9
50.33
205
37.75
125
RTT 930
800,000 930.2
53.33
220
40.00
140
(*)
∆
t = temperature difference
NOTA:
The RTT boiler has been designed only for heating systems
with forced circulation of hot water.
1.16
Gas side resistor and output temperature of
combustion gases
0,30
100
200
300
400
500
600
700
800
900
1,20
2,10
2,70
3,30
4,50
5,10
5,70
3,90
Heat output (kW)
Gas side resistance (mbar
)
Full load
Part load
100
130
180
200
220
160
10
20
30
40
50
60
70
80
90
100
Exit flue gas temperature (°C)
Load (%)
1.17
User instructions
Heating system
The difference in temperature between the supply temperature
and the water return temperature should not exceed 20°C. The
temperature of the return water should higher than 50-55 °C.
Use the boiler's protection pump to raise the temperature of
the return line water. The water level in the system should be
measured every day (if the circuit is open with a water gauge, if
closed with a pressure gauge) topping up with water if the level
is too low. Do not add water when the system is hot. If there are
problems that are causing leaks, these should be dealt with as
soon as possible. The water circuit should be made by certified
professionals, in conformity with the requirements and using
the materials specified in current regulations.
Connections to the electrical system and fuel delivery system
These connections should be made by certified professionals, in
conformity with the requirements and using the materials spec-
ified in current regulations. Burner, control panel, Ecopanel etc.:
read the warnings and the instruction manuals provided by the
manufacturer of by the distributor. The burner should not start
before the boiler's recirculation pump is running. If there is a
fault with the recirculation or protection pump, switch off the
burner. The operation of the systems should be coordinated. Do
not switch on the pumps when the water temperature is at 40
°C or higher. The recirculation pump and the burner should op-
erate contemporaneously.
The protection pump should be chosen taking into account the
boiler capacity. The connection of the pumps to the manifolds
should be carried out correctly with valve and thermostat. In this
way the system will stop at the temperature that has been set. If
