Pump Available Head; Safety Pressure Relief Valve; Choice Of The Location; Location Of The Boiler - Baxi COMBI 224 Installation And Service Manual

Fig.10 Pump available head graph
6.0
5.5
5.0
4.5
4.0
3.5
85%
3.0
2.5
2.0
1.5
0 200 400
Q (l/h)
Fig.11 Discharge pipe
A
5.3

Choice of the location

7661586 - 2 - 12072016

5.2.9 Pump available head

This is a two-speed (85% CH and 100% DHW) high static head pump fit
for installation on any type of single or double pipe CH system. The auto­
matic air valve incorporated in the pump allows quick venting of the heat­
ing systems.
Tab.18 Pump head
100%
Q
H
1000
600 800
PN-0000270

5.2.10 Safety pressure relief valve

1
2
A
1
The pressure relief valve is set at 3 bar, therefore all pipework, fittings, etc.
should be suitable for pressures in excess of 3 bar and temperature in ex­
cess of 100°C.
2
The pressure relief discharge pipe should be not less than 15mm diame­
ter, run continuously downward, and discharge outside the building, pref­
erably over a drain. It should be routed in such a manner that no hazard
occurs to occupants or causes damage to wiring or electrical components.
If it is anticipated that any part of the pipe may be subject to freezing it
should be suitably insulated. The end of the pipe should terminate facing
down and towards the wall.
1
The discharge must not be above a window, entrance or other public ac­
PN-0000272
cess. Consideration must be given to the possibility that boiling water/
steam could discharge from the pipe.
A remote relief valve kit is available to enable the boiler to be installed in
cellars or similar locations below outside ground level.
A boiler discharge pump is available which will dispose of both condensate
& high temperature water from the relief valve. It has a maximum head of
5 metres.

5.3.1 Location of the boiler

The boiler may be fitted to any suitable wall with the flue passing through
an outside wall or roof and discharging to atmosphere in a position permit­
ting satisfactory removal of combustion products and providing an ade­
quate air supply. The boiler should be fitted within the building unless oth­
erwise protected by a suitable enclosure i.e. garage or outhouse. (The
boiler may be fitted inside a cupboard.
Where the boiler is sited in an unheated enclosure and during periods
when the heating system is to be unused it is recommended that the per­
manent live is left on to give BOILER frost protection. NOTE: THIS WILL
NOT PROTECT THE SYSTEM !
Flow
Head
Discharge pipe
Pressure relief valve
The end of the pipe should terminate facing down and towards the
wall
See
See BS 6798 for full details.
Note
The relief valve must never be used to drain the system.
5 Before installation
85% Speed in the CH
mode
100% Speed in the
DHW mode
27