Hamworthy Purewell VariHeat 70c, Installation, Commissioning And Servicing Instructions

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HAMWORTHY HEATING LTD
1
PUREWELL Vari
Heat c
500001169/T
1.0 INTRODUCTION
1.1
A competent person holding ‘GAS SAFE’
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 Vari
Heat
is a fully modulating, pre-
mix condensing, gas fired boiler manufactured from
horizontal cast iron heat exchanger sections,
connected to an economiser located in the base of
the boiler. 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 Vari
Heat
boiler is delivered to site
fully assembled fitted with it’s casing and 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 a draught stabiliser is
recommended for some installations—see Appendix
‘C’ (Page 48).
1.3.4
The Purewell Vari
Heat
has a low water content
and minimum flow rates
MUST
be maintained above
the recommended levels shown in Appendix
‘E’ (Page 52)
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
.
Consideration should also be given to the maximum
working pressure of the boiler as per Appendix ‘E’.
Consult Hamworthy Heating Technical Department
for help or assistance if in doubt.
1.5
The Purewell Vari
Heat
boiler is not suitable for
direct connection to domestic hot water supplies or
gravity fed heating systems.
1.6
The Purewell Vari
Heat
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
formation of lime scale and black iron oxide sludge.
The high efficiencies produced by the Purewell
Vari
Heat 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.
1.8
Each Purewell Variheat module is supplied 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
1.9.1
Optional reverse return header kits are
available in 2, 3 & 4 boiler configuration covering
models 70c , 95c, 110c, 140c & 180c. These kits
incorporate all necessary valves and interconnecting
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:
1.9.3
External sensor
Allows direct weather compensation on an individual
boiler. Not to be used for multiple boiler systems.
1.9.4
Clip in module (LPB Bus)
Allows communication with multiple boilers under the
control of a Merley cascade control.
1.9.5
Merley cascade control
Allows cascade management of up to 12 boilers, and
interface with a BMS system.
1.9.6 The QAA73.210
is a digital multi-functional room
unit for one or 2 heating circuits and d.h.w. control.