08.04.2021
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CONDENSINOX -
Installation, Use and Maintenance
4.5. Hydraulic connection
The presence of a water pump built into the boiler with intelligent
regulation allows optimum operation at up to Pinst/35 (Pinst =
instantaneous power expressed in Th/h – 1 Th/h = 1.163 kW).
Below this rate of Pinst/35, the boiler will continue to operate but with a
gradual reduction in power (the boiler will stop below Pinst/51).
Care must be taken with the exchanger never to exceed the rates
prescribed in paragraph 3.3 (nominal boiler power/7).
The system circulating pump(s) must be sized for the maximum power
supplied.
The pipes connecting the boiler to the installation must be specified carefully
to minimise pressure losses and so avoid overspecified circulating pumps.
In some cases the diameter of the connection pipes will be greater than the
diameter of the boiler tappings. The diameter can then usefully be increased
after the union connectors, the stop valves, and/or the hydraulic balancing
valves.
The diagram below allows approximate sizing of these pipes: Note that this
does not take account of bends, reductions, valves etc. along the way that
can have a significant impact on total pressure loss in the ducts.
figure 11 -
Diagram of regular pressure drops in steel ducts (cold water)
1
10
10
100
1000
1''
1''¼
1''½
¾''
2
3
4
5
6
7
8
9
Débit en m³/h
P
er
te de c
har
ge,
en m
m
C
E
par
m
èt
re de c
ondui
te
Diagramme des pertes de charge régulières dans les conduites en acier (eau froide)
20
30
40
50
60
80
200
300
400
500
600
800
Pressure drop in mmCE per metre of duct
Flow rate in m
3
/h
