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MHG Heating Ltd, Unit 4 Epsom Downs Metro Centre, Waterfield, Tadworth, Surrey, KT20 5LR
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010617
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10.0 Filling The System
The Initial filling of a sealed heating system, and subsequent refilling, must be by a
method that has been approved by the Water Regulation Advisory Scheme (WRAS) for
that type of heating system.
i.e.
Domestic (
In-House)
Fluid Category 3 (
C-3)
Non Domestic (Other than
In-House)
Fluid Category 4 (
C-4)
For Category 3 systems, the approved method of filling must comprise of the
following components in the arrangement shown;
Control Valve incorporating a Double
Check Valve on the Mains Cold Water
pipework.
Temporary Connecting Hose, which
must be disconnected after use.
Control Valve, on the heating system.
For Category 4 systems, the approved method of filling must comprise of the
following components in the arrangement shown;
Control Valve.
Strainer.
Verifiable Backflow Device with
Reduced Pressure Zone (RPZ Valve)
Incorporating a ‘Type BA’ Air Gap.
Tundish.
Control Valve.
Further more, in accordance with BS 6644: 2005 system with an input greater than
70kW (nett), an automatic water replenishment unit shall be installed to
automatically replenish any lost or evaporated water.
Please refer to BS 6644: 2005 for allowable water replenishment methods for use
with sealed/pressurized heating systems.
For information on a comprehensive range of pressurization units that comply with
current British Standards and WRAS Regulations, please contact MHG Heating Ltd
Sales.
