Page 1
Offer the plate to the wall in the position where the programmer is to be mounted, remembering that
The Backplate may be fitted directly on to a single gang steel flush wiring box complying with BS4662,
425 Electro-Mechanical Programmers are suitable for mounting on a flat surface only, they must not be
All necessary electrical connections should now be made. Flush wiring can enter from the rear through
PAGE 1AGE 4
ISSUE 11
FITTING THE PROGRAMMER
oosen the two ‘captive’ retaining screws on the top of the unit. Now fit
onnection blades on the back of the unit locate into the terminal slots
ecurely, then switch on the mains supply.
t:0117 9788 773 - f:0117 9788 701
ighten the two ‘captive’ retaining screws to fix the unit
The tappets can now be set to suit the User’s requirements.
Please refer to the User’s Guide provided.
ENDVIEWOF425 ELECTRO-MECHANICALPROGRAMMER
The 425 Range of traditional Electro-mechanical
Programmers offer a simple yet effective way
of controlling your environment. The twin circuit
Diadem and Tiara will also allow you to have
independent control of Hot water and Central
heating.
INSTALLATION AND CONNECTION SHOULD ONLY BE CARRIED OUT BY A SUITABLY QUALIFIED PERSON
AND IN ACCORDANCE WITH THE CURRENT EDITION OF THE IEE WIRING REGULATIONS.
SPECIFICATION: CORONET - DIADEM - TIARA
Single Circuit 13(6)A 230V AC
Double Circuit 6(2.5)A 230V AC
Double Circuit 6(2.5)A 230V AC
Micro dis-connection(Voltage free)
230-240V AC 50Hz
IP 20
55oC
Normal situations.
Electronic Time Switch
Continuous
Thermoplastic, flame retardant
153mm x 112mm x 33mm
24 hour
24 Hours, On all day, Twice, Off
Two
Instant advance
9 Pin terminal connection
GENERAL INFORMATION
WARNING:ISOLATE MAINS SUPPLY BEFORE COMMENCING INSTALLATION
FITTING THE BACKPLATE
Once the Backplate has been removed from
the packaging please ensure the programmer
is re-sealed to prevent damage from dust,
debris etc.
The Backplate should be fitted with the
wiring terminals located at the top and in a
position which allows the relevant clearances
around the programmer. (See diagram)
DIRECT WALL MOUNTING
the Backplate fits to the right hand end of the programmer.
Mark the fixing positions through the slots in the Backplate(Fixing centres 60.3mm), drill and plug the
wall, then secure the plate in position. The slots in the Backplate will
compensate for any misalignment of the fixings.
WIRING BOX MOUNTING
using two M3.5 screws.
positioned on a surface mounted wall box or on unearthed metal surfaces.
ELECTRICAL CONNECTIONS
Email: sales@horstmann.co.uk
Horstmann Controls Limited
Bristol
BS4 1UP
LEAFLET No P27673
the aperture in the Backplate. Surface wiring can only enter from beneath the programmer and must
be securely clamped.
The mains supply terminals are intended to be connected to the supply by means of fixed wiring.
The recommended cable sizes are 1.0mm2or 1.5mm2for a Diadem/Tiara and 1.5mm2for a Coronet.
Page 2
onductors are left protruding outside the central space enclosed by the Backplate.
ELECTRICAL CONNECTIONS
lot and rotate anti-clockwise until the slot is almost horizontal (a stop will prevent the interlock from
PAGE 3
arth continuity must be maintained and all bare Earth conductors must be sleeved. Ensure that no
CORONET
INTERNAL WIRING DIAGRAMS
DIADEM / TIARA
Neon shown is only
on the 425 Diadem.
TYPICAL WIRING DIAGRAMS
Example circuit diagrams for some typical installations are shown below. These diagrams are
schematic and should be used as a guide only.
Please ensure that all installations comply with the current IEE regulations.
For reasons of space and clarity not every system has been included and the diagrams have been
simplified, for instance some Earth connections have been omitted.
Other control components shown in the diagrams i.e. Valves, RoomStats etc are general
representations only. However the wiring detail can be applied to the corresponding models of most
manufactures e.g. Horstmann, Honeywell, Danfoss Randall, ACL Drayton etc.
Cylinder and Room Thermostat Key:
C = Common CALL = Call for heat or break on rise SAT = Satisfied on rise N = Neutral
When used to control MAINS VOLTAGE
SYSTEMS Terminals L and 5 should be
electrically linked by means of a suitable
piece of sleeved conductor. When used to
control EXTRA LOW VOLTAGE SYSTEMS
these links MUST NOT be fitted.
When used to control MAINS VOLTAGE
SYSTEMS Terminals L,2 and 5 should be
electrically linked by means of a suitable
piece of sleeved conductor. When used
to control EXTRA LOW VOLTAGE SYSTEMS
these links MUST NOT be fitted.
INTERLOCKING - DIADEM AND TIARA ONLY.
his is achieved by rotating the interlock located at the top of the HW programme slide.
his is achieved by first selecting Twice on the HW selector slide, then selecting the Off position on the
425 Coronet controlling typical
combination boiler installation
via room thermostat.
425 Diadem/Tiara controlling
gravity Hot water with pumped
Heating via room stat.
425 Coronet controlling gravity
Hot water with pumped Heating
via room stat and cylinder stat.
425 Diadem/Tiara controlling
gravity Hot water with Pumped
Heating via room stat and cylinder
stat.
425 Coronet controlling fully
pumped system via room stat,
cylinder stat and using a 2 port
spring return valve with auxiliary
switch on heating circuit.
425 Diadem/Tiara controlling
gravity Hot water with pumped
Heating using a 2 port spring return
valve with auxiliary switches via a
room stat and cylinder stat.
425 Tiara controlling fully pumped
system using two motorised 2
port valves with auxiliary switches
via room stat and cylinder stat.
425 Diadem/Tiara controlling gravity
Hot water with pumped heating
using a 2 port spring return valve
with changeover auxiliary switch on
425 Tiara controlling fully pumped
system using a mid position valve
via room stat and cylinder stat.
Loading...