CONTENTS
i System Diverter Valve kit 6 720 645 222 (2012/09)
2
CONTENTS
1 Key to symbols and safety precautions . . . . . . . . . . . . . . . . . . . 2
1.1 Explanation of symbols . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
2 Plumbing manifold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
3 Boiler connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3.1 Assembly of internal cylinder return pipe to the boiler . . 4
3.2 Gas and water connections . . . . . . . . . . . . . . . . . . . . . . . 5
4 Fitting the diverter valve motor and code plug . . . . . . . . . . . . 6
4.1 Fitting the diverter valve motor: . . . . . . . . . . . . . . . . . . . . 6
4.2 Access to the code plug . . . . . . . . . . . . . . . . . . . . . . . . . . 6
4.3 Fitting the code plug . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
5 DHW monitoring and control . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
5.1 Cylinder temperature sensor/thermostat . . . . . . . . . . . . 7
5.1.1 Fitting the cylinder temperature sensor . . . . . . . . . . . . . 7
5.1.2 Fitting the cylinder thermostat . . . . . . . . . . . . . . . . . . . . . 7
5.2 Diverter valve and sensor connections . . . . . . . . . . . . . . 8
5.3 Diverter valve and cylinder thermostat connections . . . 8
6 Electrical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
6.1 Internal diverter valve with a vented cylinder and DHW
cylinder sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
6.2 Internal diverter valve with a vented cylinder and DHW
cylinder thermostat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
6.3 Internal diverter valve with an unvented
cylinder and DHW cylinder thermostat only . . . . . . . . . . 9
6.4 Position of wired components . . . . . . . . . . . . . . . . . . . 11
7 Pre-commissioning checks . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
8 Boiler function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
8.1 Fault finding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
8.2 Boiler function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
8.3 Protection function . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
1 KEY TO SYMBOLS AND SAFETY
INSTRUCTIONS
1.1 EXPLANATION OF SYMBOLS
WARNING SYMBOLS
Signal words indicate the seriousness of the hazard in terms of the
consequences of not following the safety instructions.
•NOTICE indicates possible damage to property or equipment, but
where there is no risk of injury.
•CAUTION indicates possible injury.
•WARNING indicates possible severe injury.
•DANGER indicates possible risk to life.
IMPORTANT INFORMATION
ADDITIONAL SYMBOLS
SYMBOLS USED IN THIS MANUAL
PLEASE READ THESE INSTRUCTIONS CAREFULLY BEFORE
STARTING INSTALLATION.
ABBREVIATIONS USED IN THIS MANUAL:
NOTICE: Safety precautions and standards
▶ Refer to the relevant Installation, Commissioning and
Service instructions for Safety precautions and
British standards
Safety instructions in this document are framed and
identified by a warning triangle which is printed on a
grey background.
Important information in cases where there is no risk of
personal injury or material losses is identified by the
symbol shown on the left. It is bordered by horizontal
lines above and below the text.
Symbol Meaning
▶ a step in an action sequence
a reference to a related part in the document or to other
related documents
• a list entry
–a list entry (second level)
Domestic Hot Water
Central Heating
Hot Water Storage Cylinder
Domestic Cold Water Supply
Electrical Supply
Gas Supply
These instructions are applicable to the Worcester appliance model(s)
stated on the front cover of this manual only and must not be used with
any other make or model of appliance.
These instructions apply in the UK and Ireland only and must be
followed except for any statutory obligations.
This appliance must be installed by a GAS SAFE registered,
competent person. Failure to install correctly could lead to
prosecution.
If you are in any doubt, contact the Worcester Technical help-line
(0844 892 3366).
Please leave these instructions with the completed BENCHMARK
CHECKLIST, (or a certificate confirming compliance with IS 813, Eire
only) and the user manual with the owner or at the gas meter after
installation or servicing.
Distance learning and training courses are available from Worcester.
The BENCHMARK CHECKLIST can be found in the back of the
Installation, Commissioning and Servicing instructions.
ØDiameter
NG Natural Gas
LPG Liquid Petroleum Gas
CH Central Heating
DHW Domestic Hot Water
PRV Pressure Relief Valve
PTC Positive Temperature Coefficient (sensor)
NTC Negative Temperature Coefficient (sensor)
IP Ingress Protection
RCD Residual Current Device
TRV Thermostatic Radiator Valve
WRAS Water Regulations Advisory Scheme
SEDBUK Seasonal Efficiency of Domestic Boilers in the U.K.
