Installation of air bleed valves at the high spot(s) in the system will allow for air
elimination when filling the system and will allow re-venting in a day or so after all
air has been driven out of solution.
2.7.7
System Pump Selection (if required)
The C45, C40P and C55(P)
feature an integral circulating
pump which has sufficient
excess head to drive most
domestic
systems.
The
available head is indicated in
the chart below. If the system
index circuit resistance, at the
desired flow rate, is in excess
of the available head from the
integral pump an additional
system pump will be required.
The
schematic
above
illustrates
a
recommended
approach
to
using
an
additional system pump. The
additional system pump should
be sized to overcome the index
circuit resistance only as the
boilers
integral
pump
will
overcome boiler resistance.
If an additional pump is
required the selected pump
must comply with BS 1394.
2.8
FLUE SYSTEM
2.8.1
Design
Individual air supply and flue outlet pipes are used. The material used for flue
outlet &/or air inlet must be muPVC to BS5255 and/or BSEN1566-1 and
BSEN1329 of an internal diameter of 51 mm. (i.e. nominal 50 mm diameter
muPVC solvent weld waste pipe). Marley muPVC Solvent Weld Waste System
(50mm) and Polypipe System 2000 muPVC Solvent Weld Waste (50mm) are
recommended systems. DO NOT USE ABS PIPE OR FITTINGS.
WD536
Chapter 2 - Boiler Location
The Keston C45, C40P, C55 & C55P
Installation & Servicing Instructions
Page : 14
Fig 2.7.7 Available Pump Head Graph
10
20
30
40
50
60
1.0
2.0
3.0
4.0
5.0
6.0
Water Flow - L/min
St
at
ic
P
re
ss
ur
e
- m
W
C
8.0
7.0
C45/C55
Additional system
pump.
Primary flow
Primary Return
Expansion
Vessel
Safety
Valve
AAV
42mm
Header