Introduction - Hamworthy Purewell VariHeat 65he Installation, Comissioning And Servicing Instructions

1.0 INTRODUCTION

1.1 A competent person holding 'CORGI' registration
or equivalent must install this boiler. All installations
MUST conform to the relevant Gas Safety and
Building Regulations. Health & Safety requirements
must also be taken into account when installing any
equipment. Failure to comply with the above may
lead to prosecution.
1.2 These instructions are for Group H Natural Gas
(2nd Family) only. The information relating to Natural
Gas firing is to be found in Appendix 'A'. Boilers MUST
NOT use gas other than that for which they were
designed and made.
1.3 The Purewell VariHeat he is a fully modulating,
high efficiency, pre-mix type gas fired boiler.
Manufactured from
exchanger sections.
The boiler is floor mounted and is intended for the
heating of Commercial and Industrial premises. It
may also be used to supply hot water for these
premises via an indirect cylinder.
1.3.1 Each boiler module has a dedicated Siemens LMU
microprocessor based boiler management system,
controlling and monitoring all safety and functional
aspects of the boiler performance and it's integration with
external system controls.
1.3.2 The Purewell VariHeat he boiler is delivered to
site fully assembled
controls. Care should be taken when manoeuvring
the boiler into position to avoid damage.
1.3.3 Each of the boiler models is designed for direct
connection to a flue system. The flue system must be
suitable for pressurised wet operation. The flue
outlets from more than one unit may be connected to
a single chimney. No draught diverter is fitted to the
boiler nor is a fixed diverter required in the flue
system. However
recommended for some installations—see Appendix
'C' (Page 44).
The Purewell VariHeat he has a low water
1.3.4
content and minimum flow rates MUST be maintained
above the recommended levels shown in Appendix
'E' (Page 48)
1.4 If the boiler is to be connected to an un-vented
(pressurised) heating system, care must be taken to
ensure all extra safety requirements are met and that
the relevant interlocks will shut down the boiler(s)
should a high or low pressure fault occur.
The pressurisation unit must also incorporate a low
level water switch, which protects the water pumps,
and will directly or indirectly shut down the boiler
plant should a low water condition occur.
HAMWORTHY HEATING LTD
horizontal cast iron
fitted with it's casing and
a draught stabiliser
PUREWELL VariHeat he
Consideration should also be given to the maximum
working pressure of the boiler as given in Appendix
'E'. Consult
Department for help or assistance if in doubt.
1.5 The Purewell VariHeat he boiler is not suitable for
direct connection to domestic hot water supplies or
gravity fed heating systems.
1.6 The Purewell VariHeat he boiler can be installed
with either reverse return water flow layout or with
single pipe header layout (non HHL supply). See
Appendix E for typical schematic layout.
1.7 It is good practice in all heating installations to
use some form of water treatment to reduce
heat
formation of lime scale and black iron oxide sludge.
The high efficiencies produced by the Purewell
VariHeat he Boiler can easily be reduced by lime
scale formation. If a pressurisation unit is used, it is
prudent to include an hours run meter to give an
indication of pump running time and hence raw water
make-up. Any leaks should be attended to as soon as
possible to avoid scale build up within the boiler's
waterways.
Each Purewell VariHeat he boiler is supplied
1.8
with volt free contact outputs for Normal Run, Boiler
lock-out from a General Fault, 0~10v analogue
control input. Also provided are connections for BMS,
Shunt Pump & Remote On/Off control as well as
connections to a boiler lock circuit (causing the boiler
to go to standby).
1.9 Options
Optional reverse return header kits are
1.9.1
available in 2, 3 & 4 boiler configuration covering
models 65he, 85he, 105he, 125he. These kits
incorporate all necessary valves and interconnecting
is
pipework. Refer to individual kit instructions for
details.
1.9.2 Controls peripherals
The LMU boiler management system has the potential to
accept the following control options:
1.3.1.2 External sensor
Allows direct weather compensation on an individual
boiler. Not to be used for multiple boiler systems.
1.3.1.3 Clip in module (LPB Bus)
Allows communication with multiple boilers under the
control of an RVA47 cascade control.
1.3.1.4 RVA47 cascade control
Allows cascade management of up to 12 boilers, and
interface with a BMS system.
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Hamworthy Heating Technical
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