10
221788B
3 Water Systems
3.5 Domestic Hot Water System
General. The domestic hot water service must be in accordance
with the current issue of BS5546, refer also to the current issue
of BS6700.
3.6 Indirect Cylinder
For all systems supplying domestic hot water the cylinder must
be indirect. It is recommended that the indirect cylinder be fitted
with some form of temperature control.
3.7 Gravity Domestic Hot Water with Pumped
Heating
Important: If domestic hot water is to be provided by a gravity
circulation to the indirect cylinder the blanked off connections
must be opened and used, using 22x28mm connections, see
diagram 3.3.
3.8 Fully Pumped Heating and Domestic Hot
Water
The connections for this type of system MUST be as shown in
diagram 3.2 and 3.4.
3.9 Inhibitor
Attention is drawn to the current issue of BS5449 and BS7593
on the use of inhibitors in central heating systems.
If an inhibitor is to be used, contact a manufacturer or
Hepworth Heating Ltd., for their recommendations as to the
best product to use.
When installing in an existing system take special care to drain
the entire system, including radiators, then thoroughly cleaning
out before installing the boiler whether or not adding an inhibitor.
1metre Min.
27 metres
Max.
22mm VENT & 15mm COLD FEED
TO BE FITTED IN ACCORDANCE
WITH BS 5449
INDIRECT
CYLINDER
ALTERNATIVE
SYSTEM
CONTROL
VALVES
HEATING
SYSTEM
PUMP
FULLY PUMPED CIRCULATION
SYSTEM (DIAGRAMMATIC)
IF REQUIRED
BYPASS 15mm
MIN WITH
LOCKSHIELD
VALVE
Diagram 3.4
22mm
PIPE
RETURN
FLOW
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