10
PLUMBING (BOILER MODEL)
REGULATIONS
The plumbing must be in accordance with all
relevant regulations and practices. It must include a
gravity circuit with expansion pipe, open to the
atmosphere. The central heating will normally be
pump-driven as with other types of boilers.
GRAVITY CIRCUIT
The gravity circuit consists of the domestic hot water
tank of 135 litres indirect cylinder, fixed in an upright
position, recommended for hot water storage and it
should be connected to the boiler by 28mm diame-
ter flow and return piping. The pipes should not
exceed 7.8 meters (25ft) in length and cylinder and
pipework should be fully lagged. The shorter the run
of pipe work the more effective the water heating.
Fig.8
WARNING:
DO NOT OBSTRUCT PRIMARY
AIR SUPPLY TO THE SPIN VALVE AT THE
FRONT OF THE STOVE
There must be no gate valves on this circuit and it
must have an expansion pipe exhausting to atmos-
phere. Cylinder and pipe work should be lagged to
minimise heat loss.
This diagram illustrates the basic principal of water
heating systems and must not be regarded as a
working drawing.
PLUMBING
INTERLINK SYSTEM
Fig. 9