Dimplex SOLAR ST0133 - Manual (Page 30)

Technical manual
Page 30 of 72
ST0133 – A 02/09
SOLAR
Insulation cover (12)
The insulation cover avoids unnecessary heat loss from the solar loop and gives the
pump unit its aesthetically pleasing appearance.
4.3.2 Pump connection
The connection of the circulation pump to the control unit has to be considered in its
application for:
- open vented hot water systems
- closed unvented hot water systems
When installing the solar thermal system in conjunction with an open vented system,
the pump can be directly wired into the control unit as shown in the control unit manual.
When using an unvented hot water system, the pump has to be wired through the twin
thermostat at the cylinder. Figure 31 shows the wiring schematic utilising the 4-way
wiring centre provided with the pump unit.
Figure 31 – Wiring of solar circulation pump to control unit utilising 4-way wiring centre
The use of a motorised two port valve is not required as long as:
- the pump unit has a non return valve in flow and return
- the circulation pump is connected using the twin thermostat mounted to the cylinder
- the cylinder is situated lower in the property than the lowest part of the solar collector
C 1 2 C 1 2
L
N
Control Unit
Solar pump
Twin tank
thermostat