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- In hard water areas it may be beneficial to install a proprietary water conditioning device in the water supply to the
water heater to reduce the deposition of lime scale in the water heater.
Installation – Mounting
- Using Diagram 2 as a guide decide on a suitable position for the water heater.
- The water heater base moulding incorporates integral mounting feet which should be placed on a level surface.
- It is recommended that the unit is mounted with the terminal covers towards the front of the unit to allow access to
the temperature sensor mounting pocket.
Diagram 3 – Installation scheme
Installation – Plumbing
- Refer to section IMPORTANT INSTALLATION POINTS. Plumb in valves in the sequence shown in Diagram 3.
Ensure the valves are installed in the correct orientation by reference to the direction of flow arrows marked on
them.
- The water connections on the unit accept direct connection of 22mm outside diameter pipe; nuts and olives are
supplied for this purpose. The thread on the connections is G3/4 to enable the use of G3/4 female connections to be
used if required.
- The sanitary water INLET is marked BLUE, the OUTLET is marked RED. Several hot outlets can be served,
however, individual site demands should be considered when choosing capacity and the number of outlets to be
served.
- It is recommended that an isolating valve is fitted on the cold water supply to the heater.
- A drain cock must be fitted below the heater in the inlet pipework. It must be sited between the heater and the Check
Valve (see Diagram 3)
- A sanitary circuit expansion vessel may be fitted to the cold water to prevent wastage of expanded water. An 18litre
vessel is recommended.
- A re-circulation circuit can be installed on the sanitary water circuit. A connection is provided for the re-circulation
circuit return pipe (threaded G1/2 female). This connection is supplied with a blanking plug fitted which should be
removed before connecting the re-circulation circuit return pipe.
- The solar coil (lower coil in the twin coil model) must be connected to a fully pumped solar primary circuit. The solar
primary circuit should have its own dedicated circulating pump and safety controls which must be installed according
to the manufacturers instructions.
- The auxiliary primary heating circuit (the upper coil in the twin coil model) MUST be fully pumped. Gravity circulation
will not work due to the special design of the primary heat exchanger. It is recommended that an air bleed point or
automatic air vent is incorporated in the primary return pipework close to the water heater.
10
8
9
4
3
2
1
6
7
5
1
Inlet water tap
2
Inlet filter
3
Pressure regulator
4
Check valve
5
Safety valve (rated 8 bar)
6
Sanitary expansion vessel
7
Draining valve
8
Recirculation pump
9
Solar circuit pump group
(including all control
components: expansion vessel,
safety valve, shut-off valves,
pressure guage, temperature
guage and flow meter)
10
Vent valve located near
collector
Note: This layout is purely indicative and
actual layouts must be verified by a
proper technical analysis.
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