Technical data

L
N
1 2 3
Control Housing Details
Element Connections
1.5mm² 3 Core
HOFR sheathed
cable
Indirect control
wiring
Fig 9 - Indirect Electrical connections (schematic)
INSTALLATION - INDIRECT UNITS
PLUMBING CONNECTIONS
PremierPlus indirect cylinders require the following pipework connections.
Cold water supply to and from inlet controls.•
Outlet to hot water draw off points. •
Discharge pipework from valve outlets to tundish•
Connection to the primary circuit.•
All connections are 22mm compression. However, 3/4”BSP parallel threaded ttings can be tted to the primary coil
connections if required.
ELECTRICAL SUPPLY
All units are tted with a 3kW immersion heater and a combined thermostat and thermal cut-out to control the indirect
heating source. The PremierPlus cylinder MUST be earthed. All wiring to the unit must be installed in accordance with
the latest IEE Wiring Regulations and the supply circuits must be protected by a suitable fuse and double pole isolating
switch with a contact separation of at least 3mm in both poles. All connections are made to the terminal block located
under the terminal cover mounted on the side of the unit. The supply cable(s) must be routed through the cable grip(s)
in the terminal housing.
DISCONNECT FROM MAIN SUPPLY BEFORE REMOVING ANY COVERS. DO NOT BYPASS THE THERMAL CUT-OUT(S) IN ANY
CIRCUMSTANCES. Ensure the thermostat and thermal cut-out sensing bulbs are pushed fully into the pockets on the element
plate assembly.
BOILER SELECTION
The boiler should have a control thermostat and non self-resetting thermal cut-out and be compatible with unvented storage
water heaters.Where use of a boiler without a thermal cut-out is unavoidable a “low head” open vented primary circuit should
be used. The feed and expansion cistern head above the PremierPlus cylinder should not exceed 2.5m.
PRIMARY CIRCUIT CONTROL
The 2 port motorised valve supplied with the PremierPlus cylinder MUST be tted on the primary ow to the PremierPlus cylinder
heat exchanger and wired in series with the indirect thermostat and thermal cut-out tted to the unit. Primary circulation to
the PremierPlus cylinder heat exchanger must be pumped; gravity circulation WILL NOT WORK.
SPACE AND HEATING SYSTEMS CONTROLS
The controls provided with the PremierPlus cylinder will ensure the safe operation of the unit within the central heating
system. Other controls will be necessary to control the space heating requirements and times that the system is required
to function. (See Fig. 9, page 13)
The PremierPlus cylinder is compatible with most heating controls, examples of electrical circuits are shown in Figs. 10 and
11 (page 14). However, other systems may be suitable, refer to the controls manufacturers’ instructions, supplied with the
controls selected, for alternative system wiring schemes.
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