User guide

10
Connections for 2 or more boilers.
1 CONN5: Main power-supply cables. Connect each boiler to its supply live, neutral, and earth, as
described above. The supplies to each boiler can be on different phases if using a 3-phase supply.
2 CONN1 pins 2 & 3: Control signal. Join all the boiler ‘R’ terminals on the control terminal block
together, and then connect them to the switched live control signal to the programmer control
circuit. Connect all the boiler ‘N’ terminals on the control terminal block together and then to neutral
on the programmer control circuit.
3 CONN1: Pump connections. The pump must be connected through a relay assembly to ensure
that the pump always operates if any one boiler is running. See page 26. Relay box 95970135 is
required for a two boiler system and 95970136 is required for a 3 boiler system.
Check the main electrical power connections are tight. Support the back of the PCB behind the power
terminals when tightening the main power terminals. Loose connections can cause a re and will invalidate
the warranty.
The control RUN signal is optically isolated from the main boiler supply to enable different phases to be
used between boilers. The control signal required to operate the boiler is 220V - 240V at a very low current,
typically 10mA.
WARNING: THIS APPLIANCE MUST BE EARTHED.
All exposed pipework must be earthed in accordance with IEE Regulations.
After installation, preliminary electrical checks i.e. short circuit, earth continuity, resistance to earth and
check for correct polarity etc. must be carried out.
Before connecting the electrical supply, ensure the system is full of water and set to the correct pressure
(sealed systems), check for leaks. It is essential that all the air is purged from the system. Only then can
the supply be switched on.
On completion of the work the installation must be tested to IEE Regulations and an NICEIC Inspection and
Completion Certicate must be issued.
Please take note of the installation information. If in doubt please contact your local supplier or Heatrae
Sadia.
N E L
N R E N L
CONN1 CONN5
CONSUMER UNIT
MCB MCB MCB
AIR
GAP
PUMP
AMPTEC BOILER
N L
MAINS SUPPLY
DOUBLE POLE
RCD OR DOUBLE
POLE ISOLATION
LOCAL TO BOILER
DOUBLE POLE
ISOLATION SWITCH
OR DOUBLE POLE
RCD
3A FUSED
SPUR OR MCB
HEAT RESISTANT
CABLE
DEMAND SIGNAL
FROM CONTROLS/
PROGRAMMER ETC
(SEE TYPICAL
WIRING DIAGRAMS)
TO CONTROLS
PROGRAMMER / ETC
EARTH BONDING
TO BE PERFORMED
IN ACCORDANCE
WITH BS7671
BOILER SUPPLY
MCB
L
N
FIGURE SEVEN: BOILER INTERNAL SCHEMATIC
NEL
CONN5
N R E N L
CONN1
CONTROL
ELEMENT