25
Multi Pass Oil Boilers
3 - GENERAL BOILER INFORMATION
Fig. 16 - Sealed system
3
The expansion vessel can be fitted in either the
return or flow pipework in any of the
recommended positions as shown in Fig. 16. To
reduce the operating temperature of the expansion
vessel diaphragm, position it below the pipe to
which it is connected. The expansion vessel may be
positioned away from the system, providing the
connecting pipe is not less than 13 mm diameter.
4
The pressure gauge should have an operating range
of 0 to 4 bar.
5
The safety valve, set to operate at 3 bar, should be
fitted in the flow pipework near to the boiler. The
pipework between the safety valve and boiler must
be unrestricted, i.e. no valves. The safety valve
should be connected to a discharge pipe which will
allow the discharge to be seen, but cannot cause
injury to persons or property.
6
Provision should be made to replace water lost
from the system. This can be by manual or
automatic means.
7
An automatic air vent should be fitted to the
highest point of the system.
8
All fittings used in the system must be able to
withstand pressures up to 3 bar.
9
Radiator valves must comply with the requirements
of BS 2767(10):1972.
10 One or more drain taps (to BS 2879) must be used
to allow the system to be completely drained.
11 For proprietary expansion vessel/valve/gauge
packs, refer to the manufacturers instructions for
the correct location on the heating system.
Underfloor heating systems
3.13
Fig. 17 - Underfloor system
See Fig. 17
On underfloor systems it is essential that the return is
pre-heated by mixing flow water into the return before
it enters the boiler. The return temperature must be
maintained above 55°C to prevent internal corrosion
of the boiler water jacket.
General - Grant boilers are compatible with both
copper and plastic pipe. Where plastic pipe is used it
must be of an oxygen barrier type. The first metre of
pipe connected to the boiler must be made in copper.
Sealed systems - Where a sealed heating system is
fitted to the boiler only copper tube may be used.
Underfloor systems - Plastic pipe may be used on
underfloor systems where the plastic pipe is fitted after
the thermostatic mixing valve. Copper tube must be
used for the primary pipework between the boiler and
the underfloor mixing/blending valves.
Pipework materials
3.14
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Страница 13: ...13 Multi Pass Oil Boilers 3 GENERAL BOILER INFORMATION Fig 3 Two pipe system Fig 2 Single pipe system...
Страница 19: ...19 Multi Pass Oil Boilers Fig 11 Typical conventional flue with brick chimney 3 GENERAL BOILER INFORMATION...
Страница 20: ...20 Multi Pass Oil Boilers 3 GENERAL BOILER INFORMATION Fig 12 External flue Green system...
Страница 41: ...41 Multi Pass Oil Boilers 7 BOILER SERVICING Fig 34 160 200 Baffle arrangement Left Right...
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