British Gas 330, Инструкция по использованию, установке и обслуживанию

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13 0020008877-04
4 Water System
Diagram 4.3
12999
4.8 Combined Feed and Vent
For combined feed and vent, a 22mm pipe must be fitted in
accordance with BS 5449.
4.9 Domestic Hot Water Cylinder
SINGLE FEED INDIRECT CYLINDERS ARE NOT SUITABLE
The domestic hot water cylinder must be of the double feed fully
indirect coil type.
Thermal Stores
This appliance is suitable for installation with thermal stores,
however, the appliance should be adjusted to give the maximum
31kW output.
4.10 Domestic Hot Water System - unvented
General - All domestic hot water circuits, connections, fittings
must be in accordance with the relevant standards and water
supply regulations.
For GB: Guidance G17 to G24 and recommendation R17 to
R24 of the Water Regulations Guide.
For IE: The current edition of I.S.813 "Domestic Gas Installations".
Where a storage system will not have a vent to atmosphere the
installation must comply with the building regulations and local
Water Company bylaws, see also the current issue of BS5546
and BS6700.
If fitting to an existing system the local authority should be
informed.
4.11 Sealed water Systems
The installation must comply with the appropriate requirements
of the current issue of BS4814, BS5449, BS6759, BS6798 and
BS7074 Part 1 and 2.
See diagram 4.3 for a suggested layout.
4.12 Safety Valve
A safety valve must be fitted to a sealed system.
It shall be preset, non-adjustable with a lift pressure of 3 bar,
incorporating seating of a resilient material, a test device and a
connection for drain.
The drain from the safety valve must be routed outside the
building, must not discharge above an entrance or window or
any type of public access area, be clear of any electrical fittings
and positioned so that any discharge can be seen.
4.13 Expansion Vessel
A diaphragm type expansion vessel, conforming to the current
issue of BS4814 (see also BS7074 Part 1 and 2) must be
connected at a point close to the inlet side of the circulating
pump, see the diagrammatic layout, diagram 4.3 unless laid
down differently by the manufacturer.
The expansion vessel volume depends on the total water
system volume and the initial system design pressure. For any
system an accurate calculation of vessel size is given in the
current issue of BS5449 and BS7074 Part 1.
Example: For an initial design pressure of 0.7 bar, the minimum
total vessel volume required is 0.063 x Total System Volume.
NOTE: A higher initial design pressure requires a larger volume
expansion vessel.
Guidance on vessel sizing is also given in the current issue of
BS5449 and BS7074 Part 1, for IE refer to the current edition of
I.S.813 "Domestic Gas Installations".
The charge pressure must not be less than the static head of the
system, that is, the height of the highest point of the system
above the expansion vessel.