Dimplex SCx175sd Installation And Operation Manual page 7

tampered with in any way. The valve is pre calibrated to lift at 7bar or 90 degrees centigrade and any
attempt to adjust it will invalidate the warranty and could affect the safety performance of the unit.
6.4. Inlet Group – The inlet valve group (consisting of non-return valve; line strainer; pressure
reducing valve; and pressure relief valve) should be installed in the cold water supply to the cylinder
with the arrow pointing in the direction of water flow in accordance with Fig
connected to a supply pressure of between 1.5 and 12bar. No other valve should be fitted between
this group and the cylinder.
6.5. Expansion vessel – A suitable expansion vessel with a pre-charge pressure of 3bar is supplied
for fitting to all cylinders. The expansion vessel MUST be fitted between the expansion relief valve
and the cylinder. The expansion vessel MUST be positioned with the entry point at the bottom. The
expansion vessel should be installed using a standard t-connector ensuring no other valve is between
this and the cylinder. Adjust the pressure to 3bar
IMPORTANT: Regular checks must be carried out to ensure that the expansion vessel is correctly
pressurised to 3.5 bar at all times.
6.6. Secondary circulation – If the solar cylinder installation requires a secondary circulation circuit,
a 15mm return leg, which incorporates a check valve should be connected to the secondary return of
the cylinder See fig 4.1/4.2.
IMPORTANT: If a secondary circulation circuit is installed then a larger expansion vessel may be
required to handle the increase in water volume. Calculate the additional water volume and contact
the Dimplex customer services department regarding suitable vessel sizes.
6.7. Tundish – The tundish must not be positioned above or in close proximity of any electrical
current carrying devices or wiring. The installation should conform with the requirements of item 7
below. The Tundish must be situated within 500mm of the T&P valve outlet.
6.8 Balanced Take-off – The inlet group contains a 22mm cold water take off that is of the same
pressure as that of the hot water. This outlet may connected to a mixer shower for improved mixing
performance. Do not connect this balanced cold water outlet to standard cold water taps as this
reduces the water supply to the cylinder creating poor hot water flows. A check valve should be
inserted into all Balanced take off supply lines.
6.9 Safety valves – the pressure relief valve and temperature & pressure relief valve of the
unvented system are safety devices and should only be connected as described in section 7 and fig
4.1 and not be used for any other purpose.
6.10 Programmable Time Clock - A programmable time clock must be installed to turn on either
the cylinder immersion or a separate boiler at times when the solar system is ineffective (early
mornings, evenings or night time) to ensure that the water is heated to 60oC each day
4.1. This can be
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