5
8. Electrical connections
If in doubt, consult a qualified electrician or call your local
electricity board engineer.
8.1 Electrical connection, 1 x 230 V, 50 Hz
Observe colour coding as follows:
• Brown to terminal L.
• Yellow/green to terminal E (PE).
Ensure that the earth lead is at least as long as the other two
leads.
• Blue to terminal N (neutral).
Insert the lead fully into the terminal connector and tighten the
screw firmly. Ensure that the connection is secure. Be sure to
tighten the cable restraint.
Ensure compliance with IEE Regulations. In the interests of
safety, it is recommended that a residual current device (RCD)
be installed in the supply circuit.
The pump switch should be left "on" at all times for normal
operation of the system.
8.2 Electrical connection, low-voltage pumps
(STL, SSL and STL 2.0 CN)
The low-voltage pump has added electrical protection via a safety
isolating transformer. See fig. 3, page 13, or fig. 4, page 14.
For installations where the pump has to be placed in the
bathroom (for example under the bath), we recommend that
the safety isolating transformer is placed outside the bathroom or
shower area.
The low-voltage leads from the transformer must be connected to
the two terminals marked "T" in the terminal box. As the supply is
AC, the leads can be connected to either terminal on the pump.
The low-voltage pump installation kits are supplied with 3 metres
of connecting lead. The connecting leads between the pump and
the isolating transformer can be extended up to about 15 metres.
Use 1.0 mm cable.
The safety isolating transformer must be connected to a
230-240 V, 50 Hz, supply voltage with a switched spur fused
at 5 A. The switch must have a double-pole disconnection with
a separation gap of at least 3 mm. See fig. 3, switched spur.
Ensure compliance with IEE Regulations.
Observe colour coding as follows:
• Brown to terminal L.
• Blue to terminal N.
For normal operation of the shower, the transformer can be left
permanently switched on – very little power is used when the
pump is not running.
Copper pipes should have supplementary earth bonding. Where
the earth continuity has been broken, the pump suction and
discharge pipework should be connected with earthing clamps to
BS 951 and 4 mm earthing wire.
9. Before using the pump
1. Turn on the water supply. Allow the system to fill.
2. Immediately inspect for any leaks.
3. With pump not running, allow maximum water flow, for
example remove handset from shower hose, letting the
shower hose hang into the shower tray or bath. Operate
maximum hot and cold flow for at least 2 minutes, to flush out
all debris and ensure air is thoroughly purged from the system.
4. Switch on the electricity supply to the pump. Again operate the
pump in both full hot and cold modes for about 2 minutes.
5. With the pump operating, carefully inspect again for any leaks
from all connections on both hot- and cold-feed pipes to the
pump and to the system.
After hot water has been run for several minutes, check all
hot-water connections and make sure that there are no leaks.
6. The first few times the pump is used, the insulating varnish
used on the pump motor may give off an odour. This is
perfectly normal and will diminish with use.
Warning
The pump must be earthed.
The pump must be connected to an external
mains switch with a contact separation gap
of at least 3 mm in each pole.
The pump must be connected to a 230 V, 50 Hz,
supply with a switched spur fused at 5 A
(10 A on models STP 4.0 B and STN 4.0 B).
Metal pipes must be earthed by the use of
earthing clamps to BS 951 and 4 mm earthing
wire.
Caution
Complete all pipework before making electrical
connections.
Do not allow any water to enter into the electric
terminal box.
Warning
Do not operate the pump without terminal box
cover in place.
Caution
Use the transformer supplied.
Do not connect the pump directly to 240 V.
Electrical hazard will result and the motor will be
irreparably damaged.
Warning
Do not locate 230-240 V connections, plugs or
switches within the "wet" area in accordance
with IEE Regulations.
Warning
Do not let the pump run dry.
Purge water thoroughly through the system
before switching on the electricity supply to
the pump.
Do not switch on the electricity supply.
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