8.4
Domestic Hot Water
The mains water supply pressure must be less than 5 bar. If this pressure is exceeded
a pressure reducing valve must be fitted. The final 600 mm of the mains supply pipe to
the appliance must be in copper. The flow rate of water from individual taps is dependant
on the number of outlets being operated together, as well as the length and size of
pipework in the system and the mains supply pressure flow regulators.
Whenever a pressure reducing valve or any other device containing a non-return valve
is fitted to the mains water supply pipe entering the boiler, it is recommended that a
mini expansion vessel, suitable for use on potable water, is fitted between the device
and the closed tap.
Although many of the DHW components are designed to resist lime scale formation, in
areas of hard water it may still be necessary to fit an inline chemical water softener.
For further information contact Warmflow and your local water company.
To ensure economic use, the pipe runs between the boiler and the taps should be as
short as possible and insulated to reduce heat loss. For boilers that have to be sited
remotely from the main point of use, there is likely to be very long pipe runs which can
lead to excessive water usage and poor fuel efficiency. It is recommended that a pumped
hot water return is used in order to improve HW reaction times. Contact Warmflow for
details.
Note
: An 18L/min flow restrictor has been factory fitted but can be easily removed if
required.
8.5
Removal of Flow Restrictor
FLOW SWITCH
FLOW RESTRICTOR
WASHER
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