Ravenheat HE 25 S COMPACT, Instructions For Use Installation And Servicing

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Fig.6
4.11
BOILER INTERLOCK CONTROL
Central heating system controls should be
installed to ensure the boiler is switched off
when there is no demand for heating, in
compliance with Building Regulations.
The boiler has its own built in bypass.
If the system has thermostatic radiator valves on
all radiators, or two port valves, then a bypass
circuit must be fitted with an automatic bypass
valve to ensure a flow of water should all valves
be in the closed position (fig. 6).
It is important that the system is flushed
thoroughly before the appliance is fitted or
left to operate (as recommended in BS 7593)
in order to maintain an efficiently operating
heating system. For replacement installations,
the system MUST be flushed with the old boiler
insitu, in order to prevent system debris. Once
the system has been flushed, an inhibitor
(suitable for stainless steel and aluminium heat
exchanger) should be added (see section
4.18).
4.12 DRAINING TAP
These must be located in accessible positions
to permit the draining of the whole system. The
taps must be at least 15 mm nominal size and
manufactured in accordance with BS 2879.
4.10 PIPEWORK
Copper tubing to BSEN 1057:1 2006, BSEN
1172, BSEN 1652 and BSEN 1653, is
recommended for water pipes. Jointing
should be either capillary soldered or with
compression fittings.
Where possible pipes should have a gradient
to ensure air is carried naturally to air release
points and water flows naturally to drain taps.
It should be ensured as far as possible that
the appliances heat exchanger is not a natural
collecting point for air except where providing
useful heat. Pipes should be insulated to
prevent heat loss and to avoid freezing.
Particular attention should be paid to pipes
passing through ventilated spaces in roofs
and under floors.
IMPORTANT:
A minimum length of 1 metre of copper pipe
MUST be fitted to both the flow and return, as
well as the cold mains inlet and the hot water
outlet connections from the boiler before
connecting to any plastic piping.
The water through the appliance heat exchanger
circuit must exceed the min. 2.38 gals/min. (650
L/h) when the burner is firing. It is important to
ensure that this rate is achieved when sections
of the system are shut off either manually or by
automatic controls.
If the volume of circulating water is too low, the
boiler water temperature will rise too rapidly.
This could cause noise in the system or even
cause the safety thermostat to trip.
This appliance is designed to work on a two
pipe system as shown in fig.6.