Hamworthy Purewell Manual

Installation, Commissioning
and Servicing Instructions
Atmospheric Cast Iron Boiler
40kW to 120kW Output
A TOMATIC IGNITION CONTROLS
Standard Draught Diverter
or
Low Line Draught Diverter
Purewell
Gas Fired
Modular Boiler Systems
NATURAL GAS I2H
LPG-PROPANE I
3P
IMPORTANT NOTE
THESE INSTRUCTIONS MUST BE READ AND UNDERSTOOD BEFORE
INSTALLING, COMMISSIONING, OPERATING OR SERVICING EQUIPMENT.
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Customer Services
TECHNICAL ENQ IRIES 01202 662527 / 662528
To supplemen he de ailed echnical brochures, echnical advice on he applica ion and use of produc s in
he Hamwor hy Hea ing range is available from our echnical eam in Poole and our accredi ed agen s.
SITE ASSEMBLY 01202 662555
Specialis eams are available for on si e assembly of he full range of Hamwor hy boilers (excluding
Lulwor h). Boiler sec ions for si e assembly mus be posi ioned wi hin he boiler house prior o he arrival
of he assembly eam and provide sufficien space for safe working. Handling sec ions in o boiler houses
o her han a ground level may be subjec o addi ional charges.
The normal assembly price does no include for he fi ing of boiler casings or he burner, however his can
be carried ou a he ime of build a addi ional cos .
Providing he facili ies are available on si e, a hydraulic es will be carried ou wi hin he erms of BS779.
Upon comple ion a cer ifica e of assembly and es will be issued.
COMMISSIONING 01202 662555
Commissioning of equipmen by Hamwor hy Hea ing’s own engineers, accredi ed agen s or specialis sub-
con rac ors will ensure ha he equipmen is opera ing safely and efficien ly. Hamwor hy commissioning
repor s provide a de ailed record of he original s a us of he plan , which is essen ial for fu ure rou ine
main enance and rouble free opera ion.
S andard warran y erms provide for he free of charge replacemen of defec ive par s, bu does no
include labour. When he equipmen is commissioned and rou inely main ained by Hamwor hy Hea ing
under a Service Main enance Agreemen hen he warran y erms will cover bo h par s and labour.
MAINTENANCE AGREEMENTS 01202 662555
Regular rou ine servicing by Hamwor hy Hea ing’s engineers ensures rouble free opera ion and op imum
efficiency. The frequency of visi s required is variable, dependen upon he equipmen ype and usage.
Annual service agreemen s are available on all Hamwor hy produc s o mee individual requiremen s.
Planned main enance of equipmen by rou ine servicing reduces opera ional cos s considerably below ha
associa ed wi h repair or breakdown approach.
BREAKDOWN SERVICE, REPAIR, REPLACEMENT 01202 662555
Even when he commissioning and rou ine servicing has been carried ou o he highes s andard here
are always occasions when he unexpec ed breakdowns occur. Hamwor hy provide a rapid response
breakdown, repair or replacemen service hrough head office a Poole and accredi ed agen s loca ed
hroughou he UK.
SPARE PARTS 01202 662525
A comprehensive spare par s service is opera ed from our fac ory in Poole, providing replacemen par s
for bo h curren and discon inued produc s. In some ins ances spares may be available from accredi ed
agen s.
Delivery of par s and componen s is normally from s ock wi hin 7 days. However, a 24 hour delivery
service is available for breakdowns and emergencies for he addi ional cos of he courier. Please con ac
our spares eam, providing de ails of produc ype, serial number, model or any o her iden ifying marks or
codes o de ermine par requiremen s wherever possible.

HAMWORTHY HEATING LTD. PUREWELL AUTOMATIC IGNITION 500001035/G
i
P REWELL ATMOSPHERIC HOT WATER BOILER FOR HEATING
AND DOMESTIC HOT WATER INSTALLATIONS
INSTALLATION, COMMISSIONING AND SERVICING INSTR CTIONS
A TOMATIC IGNITION CONTROLS
WITH STANDARD DRAUGHT DIVERTER (D/D)
0,50,60,70,80,95,105 & 120kW models
OR WITH LOW LINE DRAUGHT DIVERTER (L/L)
0,70 & 100kW models
NOTE: THESE INSTR CTIONS SHO LD BE READ AND NDERSTOOD BEFORE ATTEMPTING TO INSTALL,
COMMISSION OR OPERATE THIS NIT
THE P REWELL BOILER IS INTENDED FOR SE AS A COMMERCIAL APPLIANCE AND IS NOT CERTIFIED
FOR SE IN DOMESTIC APPLICATIONS OR HABITABLE AREAS.
THIS BOILER IS FOR SE ON GRO P H NAT RAL GAS (2ND FAMILY)I2H OR LPG-PROPANE (3RD FAMILY)I3P.
PLEASE ENS RE RELEVANT INFORMATION REQ IRED WITHIN DOC MENT IS FO ND RELATING TO
SPECIFIC GAS TO BE FIRED BEFORE FIRING BOILER.
THIS BOILER COMPLIES WITH ALL RELEVANT EUROPEAN DIRECTIVES.
EC TYPE CERTIFICATE No. BG/EC-87/93/20.
PRODUCT IDENTIFICATION No. 87AO20
PUBLICATION NO. 500001035
ISSUE ‘G’
JANUARY 2000

HAMWORTHY HEATING LTD. PUREWELL AUTOMATIC IGNITION 500001035/G
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THIS PAGE LEFT INTENTIONALLY BLANK

HAMWORTHY HEATING LTD. PUREWELL AUTOMATIC IGNITION 500001035/G
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CONTENTS
PAGE
INDEX ............................................................................. iii
1.0 INTROD CTION ................................................................................ 1
2.0 TECHNICAL DATA ............................................................................ 1
2.1 Overall Dimensions
2.2 Technical Da a Table
3.0 GENERAL REQ IREMENTS ............................................................ 1
3.1 Rela ed Documen s
3.2 Feed Wa er Quali y
3.3 Adequa e Wa er Flow
3.4 Time Clock Con rol
3.5 Minimum Sys em Pressure
4.0 LOCATION ......................................................................................... 4
5.0 GAS S PPLY..................................................................................... 4
5.1 Service Pipes
5.2 Me ers
5.3 Gas Supply Pipes
5.4 Boos ed Supplies
5.5 Boiler House Con rol Valve
5.6 Boiler Gas Sys em Leak Check
6.0 FL E SYSTEM .................................................................................. 5
6.1 General Requiremen s
6.2 Design Was e Gas Volume and Tempera ure
6.3 Flue Condensa ion
6.4 Ma erials
6.5 Disconnec ion
6.6 Flue Discharge
6.7 Surface Tempera ure
6.8 Flue Sys em Loca ion
7.0 AIR S PPLY ...................................................................................... 9
7.1 Air Supply by Na ural Ven ila ion
7.2 Air Supply by Mechanical Ven ila ion
8.0 WATER CIRC LATION SYSTEM ..................................................... 9
8.1 General
8.2 Pressure Relief Valve (Safe y Valve)
8.3 Open Ven Pipe and Cold Feed Pipe
8.4 Al i ude Gauge (Wa er Pressure Gauge)
8.5 Thermome er
8.6 Drain Taps
8.7 Circula ing Pump
8.8 Minimum Wa er Flow Ra es
8.9 Wa erside Pressure Drop
8.10 Con rol Schemes
8.11 Unven ed Pressurised Sys ems
8.12 Modular Boiler Con rol Schemes

HAMWORTHY HEATING LTD. PUREWELL AUTOMATIC IGNITION 500001035/G
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9.0 ELECTRICAL S PPLY .......................................................................... 8
9.1 Si e Wiring
10.0 INSTALLATION OF BOILERS ............................................................. 9
10.1 General
10.2 Hea Exchanger Insula ion Fi ing Ins ruc ions
10.3 Gas pipe Fi ing Ins ruc ions
10.4 Connec ion of Boilers o he Flue Sys em
10.5 Gas Connec ion
10.6 Wa er Connec ions
10.7 Casing and Con rols Assembly
11.0 COMMISSIONING AND TESTING ....................................................... 14
11.1 Elec rical Ins alla ion
11.2 Gas Ins alla ion
11.3 Wa er Circula ion Sys em
11.4 Commissioning he Boiler
11.5 Boiler Checks Prior o Ligh ing
11.6 Gas Pressure Adjus men and Combus ion Checks
11.7 Tempera ure Limi er (Limi Thermos a )
11.8 Safe y Checks
11.9 User’s Ins ruc ions
12.0 FA LT FINDING.................................................................................... 16
12.1 Safe y Fea ures Summary
12.2 Faul Finding Procedures
12.3 Possible Causes of Boiler Lockou
13.0 SERVICING........................................................................................... 16
14.0 REPLACEMENT OF FAILED COMPONENTS.................................... 17
15.0 RECOMMENDED SPARES.................................................................. 19
APPENDIX ‘A’ - INFORMATION RELATING TO PROPANE FIRING…...... 32
FIG RES PAGE
Figure No. 1 Performance and General Da a ........................................……. 2
Figure No. 2 Recommended/minimum wa er flow ra es.........................……. 3
Figure No. 3 Gas valve in egri y check...................................................……. 5
Figure No. 4 Mechanical ven ila ion flow ra es........................................…… 6
Figure No. 5 Hea Exchanger Insula ion Fi ing Ins ruc ions....................…… 10
Figure No. 6 Gas Pipe Fi ing Ins ruc ions……........................................…… 10/11
Figure No. 7 Enclosure assembly de ails................................................……. 12/13
Figure No. 8 Boiler ins alla ion ypical layou . Ven ed and Un-ven ed boilers. 20
Figure No. 9 Overall dimensions of boiler and recommended clearances .... 21
Figure No. 10 Fron assembly showing general layou .................................... 22
Figure No. 11 Maximum gas flows hrough pipes .........................................… 23
Figure No. 12 Si e wiring de ails..................................................................….. 24
Figure No. 13 Typical s andard boiler wiring diagram..................................…. 25
Figure No. 13a Wiring Diagram fi ed wi h Pek ron 0459 Series Igni er.......…… 26
Figure No. 14 Diagram of elec rode assembly.............................................…. 27
Figure No. 15 Diagram of various gas valves fi ed.....................................…. 28
Figure No. 16 Diagram of double gas valve layou ........................................... 29
Figure No. 17 General faul finding................................................................... 30/31
Page

HAMWORTHY HEATING LTD. PUREWELL AUTOMATIC IGNITION 500001035/G
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1.0 INTROD CTION
1.1 A compe en person holding ‘CORGI’ regis ra ion
or equivalen mus ins all his boiler. All ins alla ions
M ST conform o he relevan Gas Safe y and Building
Regula ions. Heal h & Safe y requiremen s mus also
be aken in o accoun when ins alling any equipmen .
Failure o comply wi h he above may lead o
Prosecu ion.
1.2 These ins ruc ions are for Group H Na ural Gas
(2nd Family) and LPG-Propane (3rd Family). The
informa ion rela ive o propane firing is o be found in
Appendix ’A’. Boilers M ST NOT use gas o her han
for which hey were designed and made for.
1.3 The Purewell is an a mospheric, gas fired boiler
manufac ured from horizon al cas iron sec ions,
nippled a al erna e ends. These sec ions are moun ed
on a fabrica ed mild s eel baske assembly, which
houses he burner bar and igni er assemblies. A
unique radian baffle is fi ed benea h he burner bars,
pro ec ing he floor below by reducing hea los from
he boiler.
The s andard version of he Purewell boiler is designed
o be connec ed o he flue via a specifically designed
draugh diver er. This diver er M ST be fi ed in o
he spigo on op of he hea exchanger as supplied.
NO modifica ion or variance is permi ed as his may
change opera ional charac eris ics. Flue ou le s from
more han one boiler may be connec ed oge her o
form a header.
Low Line versions have an in-buil draugh diver er
and can herefore be connec ed direc o a header
assembly via a sui able flue pipe.
1.4 If he boiler is o be connec ed o an un-ven ed
(pressurised) hea ing sys em, care mus be aken o
ensure all ex ra safe y requiremen s are me and ha
he relevan in erlocks will shu down he boiler(s)
should a high or low pressure faul occur.
The pressurisa ion uni mus also incorpora e a low
level wa er swi ch, which pro ec s he wa er pumps,
and will direc ly or indirec ly shu down he boiler plan
should a low wa er condi ion occur.
Considera ion should also be given o he maximum
working pressure of he boiler as given in Section
2:TECHNICAL DATA. Consul Hamwor hy Hea ing
Technical Depar men for help or assis ance if in doub .
1.5 The Purewell boiler is no sui able for direc
connec ion o domes ic ho wa er supplies or gravi y
fed hea ing sys ems.
1.6 The Purewell boiler can be ins alled wi h ei her
reverse re urn wa er flow layou or wi h single pipe
header layou . See Figure No. 8 for ypical schema ic
layou .
Hamwor hy Hea ing can supply a pre-designed
arrangemen of componen s, which will produce a
“reverse-re urn” assembly. Please con ac Hamwor hy
Hea ing for informa ion.
1.7 I is good prac ice in all hea ing ins alla ions o
use some form of wa er rea men o reduce forma ion
of lime scale and black iron oxide sludge. The high
efficiencies produced by he Purewell Boiler can easily
be reduced by lime scale forma ion. If a pressurised
uni is used, i is pruden o include an hours run me er
o give an indica ion of pump running ime and hence
raw wa er make-up. Any leaks should be a ended o
as soon as possible o avoid calcium sal build up
wi hin he boiler’s wa erways.
2.0 TECHNICAL DATA
2.1 Overall dimensions are shown in Figure No. 9.
Bo h single and mul i boiler arrangemen s are shown.
The Purewell boiler can be ins alled as a single uni
or in modular form where a ‘mul i’ casing reduces
required floor area. Each boiler has an independen
door for access o he con rols and o her working
componen s.
I is recommended ha a maximum of 6 boilers can
be posi ioned on 533mm (21") cen res if required.
Larger numbers should be spli in o wo or more banks
wi h 150mm (6") be ween each bank. NOTE! When
ins alling modular uni s on 533mm (21") cen res, he
casing suppor rail or spacing pla es should be fi ed
be ween each boiler before bol ing oge her. See
Section 10.1: General Installation of Boilers Ref.:
- spacing pla es for fur her informa ion.
2.2 General Informa ion and Technical Da a rela ing
o Na ural Gas is shown in Figure No. 1.
Technical da a rela ing o propane firing can be found
in Appendix ’A’.
2.3 Screw threads: All screw hreads used in he
Purewell boiler conform o he following: -
ISO 7/1 or ISO 228/1 for pipe hreads where
applicable.
ISO 262 for all general screw hreads.

HAMWORTHY HEATING LTD. PUREWELL AUTOMATIC IGNITION 500001035/G
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3.0 GENERAL REQ IREMENTS
3.1Related Documents.
Gas Safety Installations and se Regulations
1994, (As amended).
I is law ha compe en persons in accordance wi h
he above regula ions ins all all gas appliances.
Failure o ins all appliances correc ly
could lead o prosecu ion. I is in your own in eres ,
and ha of safe y, o ensure ha his law is complied
wi h.
The ins alla ion of he boiler M ST be in accordance
wi h he relevan requiremen s of he IEE Regula ions
and he byelaws of he local wa er under aking.
Figure No. 1 - Performance and General Data Information
* NOTE! Flue gas volumes are based on a gross flue gas empera ure of 100°C a 1013mbar. This is considered o
be he predic ed empera ure of he produc s in he secondary flue downs ream of he draugh diver er.
Related Documents - cont.

HAMWORTHY HEATING LTD. PUREWELL AUTOMATIC IGNITION 500001035/G
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The ins alla ion should also be in accordance wi h
any relevan requiremen s of he local gas region and
local au hori y and he relevan recommenda ions of
he following documen s: -
British Standards
BS 7074: Applica ion, selec ion and ins alla ion of
expansion vessels and ancillary equipmen for sealed
wa er sys ems. Par 2: Code of prac ice for low and
medium ho wa er sys ems.
BS 6891: Ins alla ion of low-pressure gas pipework
of up o 28mm in domes ic premises. (For larger
ins alla ions see IM/2, IM/5 and IM/16 below.)
BS 6644: Ins alla ion of Gas Fired Ho Wa er Boilers
- 60kW o 2MW.
BS 6700: Design, ins alla ion, es ing and
main enance of services supplying wa er for domes ic
use.
BS 6880: Part 1, 2 & 3: Code of prac ice for low
empera ure ho wa er hea ing sys ems of ou pu
grea er han 45kW.
BS EN 60335, Part 1. Safe y of Household &
Similar Elec rical Appliances. BS 3456, Part 201:
Elec rical S andards.
Figure No. 2 - Flow-rate/Pressure Drop Table
CP 342: Cen ralised ho wa er supply.
Par 2: Buildings o her han individual dwellings.
British Gas Publications
IM/2 Purging procedures for non-domes ic gas
ins alla ions.
IM/5 Soundness es ing procedures for indus rial and
commercial gas ins alla ions.
IM/11 Flues for commercial and indus rial gas fired boilers
and air hea ers.
IM/16 Guidance no es on he ins alla ion of gas pipework.
(Excluding domes ic ins alla ions of 25mm and below.)
Health and Safety Executive:-
Guidance note PM5 - Au oma ically con rolled s eam and
ho wa er boilers.
CIBSE Publications: - “CIBSE Guide”
I is imprac ical in his documen o specify all relevan
informa ion, bu he following ex rac s from he above
references are emphasized since failure o comply wi h
hese requiremen s will almos cer ainly resul in an
unsa isfac ory ins alla ion.
3.2 Feed water Quality
If he boiler feed wa er has a high degree of hardness,
i is recommended ha he wa er be rea ed o preven
precipi a ion of scale or sludge in he boiler wa er
passageways. De ails of addi ives can be ob ained
from any reliable manufac urer of wa er rea men
produc s or he local wa er au hori y. I should be
no ed however, ha even if he boiler wa er is of
average hardness, no requiring rea men ,
subsequen draining of he sys em for repair or
cons an make-up wa er due o an unde ec ed leak
will cause addi ional deposi s and gradual build-up of
scale. I is essen ial, herefore ha leaks are a ended
o promp ly and draining is kep o an absolu e
minimum.
I is recommended ha he sys em is flushed ou a
leas wice wi h ho wa er before any rea men is
added. If any doub exis s regarding he
I is recommended ha he sys em is flushed ou a leas
wice wi h ho wa er before any rea men is added. If any
doub exis s regarding in ernal cleanliness of an old
sys em, considera ion should be given o he fi ing of a
coarse fil er in he re urn pipework o he boilers.
3.3 Adequate Water Flow
The Hamwor hy Purewell boiler is designed as a quick
response, low wa er con en uni , o run con inuously wi h
maximum reliabili y. Care should be aken in he ini ial
design and layou having due regard for adequa e wa er
flow hrough he boilers and he influence of he sys em
con rols. NOTE! The S andards Au hori y recommend a
minimum re urn empera ure of 50°C in all hea ing
sys ems o her han condensing boilers.
Figure No. 2 shows recommended and minimum wa er
flows required. The con rol sys em and valves, where
fi ed, should be regula ed o avoid lower flows occurring.

HAMWORTHY HEATING LTD. PUREWELL AUTOMATIC IGNITION 500001035/G
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The flow corresponding o 22°C empera ure rise across
he boiler is he minimum recommended flow a any ime.
For boiler pressure drop see Figure No. 2.
3.4 Time Clock Control
In order o avoid local overhea ing and progressive
calcium deposi ion a zero flow condi ions where boilers
are opera ed from ime clocks, provision should be made
for a 5 minu e circula ing pump over-run af er he las
boiler has ceased firing.
NOTE! Time clocks should no in errup live, neu ral or
ear h connec ions, see Section 9.0: ELECTRICAL
S PPLY for de ails. See Figure No. 12 for wiring de ails.
3.5 Minimum System Pressure
To comply wi h guidance no e PM5 (Health and Safety
Executive), he minimum pressure requiremen s a he
boiler are given below as examples: -
1) Single ins alled boiler running a 82°C flow
empera ure. Minimum head required is no less han 2
me res or 0.2 bar.
2) Single ins alled boiler running a 95°C flow
empera ure. Minimum head required = 5.1 me res or
0.5 bar.
3) Modular boiler ins alla ion running a 82°C flow
empera ure and 11°C rise across sys em. Minimum
head required = 4.3 me res or 0.42 bar.
4) Modular boiler ins alla ion running a 82°C flow
empera ure and 22°C rise across sys em. Minimum
head required = 10.5 me res or 1.03 bar.
See Section 8.11 for Pressurised Wa er Sys ems.
4.0 LOCATION
4.1 (See Figure No. 9 for dimensions/weigh s and
clearances.) The loca ion chosen for he boiler M ST
permi he provision of a sa isfac ory flue sys em and an
adequa e air supply. The loca ion mus also provide
adequa e space for servicing and air circula ion around
each uni . This includes any elec rical runking laid along
he floor.
Allow adequa e space, his should no normally be less
han 460 mm. a he rear, for flow and re urn connec ions.
Also allow a leas 460 mm. on one side, he o her side
mus be no less han 150 mm. Allow 610mm (minimum)
in fron of he boiler for servicing.
The boiler mus be ins alled on a level non-combus ible
surface ha is capable of adequa ely suppor ing i s
weigh (when filled wi h wa er) and any ancillary
equipmen .
Any combus ible ma erial adjacen o he boiler and he
flue sys em mus be so placed or shielded o ensure
ha i s empera ure does no exceed 65°C.
Fur her de ails regarding boiler loca ion are given in
BS 6644.
5.0 GAS S PPLY
5.1 Service Pipes
The local gas region mus be consul ed a he
ins alla ion planning s age in order o es ablish he
availabili y of an adequa e supply of gas. An exis ing
service pipe mus no be used wi hou prior consul a ion
wi h he local gas region.
5.2 Meters
A new gas me er will be connec ed o he service pipe
by he local gas region, or a local gas region con rac or.
An exis ing me er should be checked, preferably by
he gas region, o ensure ha i is adequa e o deal
wi h he ra e of gas supply required.
5.3 Gas Supply Pipes
Supply pipes mus be fi ed in accordance wi h BS 6891
or IM/16 as appropria e. Pipework from he me er o
he boiler mus be of adequa e size. Do no use pipes
of a smaller size han he boiler gas connec ion. The
comple e ins alla ion mus be purged and es ed for
soundness as described in BS 6891 or IM/2 and IM/5
as appropria e.
See Figure No. 11 for recommended gas flows in pipes.
5.4 Boosted Supplies
Where i is necessary o employ a gas pressure boos er,
he con rols mus include a low-pressure cu -off swi ch
a he boos er inle . The local gas region mus be
consul ed before a gas pressure boos er is fi ed.
5.5 Boiler House Control Valve
A manual valve for boiler house isola ion shall be fi ed
in he gas supply line. I shall be clearly iden ified and
readily accessible for opera ion, preferably by an exi .
5.6 Boiler Gas System Leak Check
Al hough he boiler receives a gas leak check and gas
rain componen in egri y check prior o leaving he
fac ory, ranspor and ins alla ion may cause
dis urbance o unions, fi ings and gas valve assemblies’
e c. During commissioning a fur her es for soundness
should be carried ou on he boiler gas pipework and
componen s. A procedure guide is given below. Care
mus be aken no o allow leak de ec ion fluid on or
near any elec rical par s or connec ions (If used). See
Figure No. 3 - Gas valve/pipework leak check es
procedure.

HAMWORTHY HEATING LTD. PUREWELL AUTOMATIC IGNITION 500001035/G
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To Check Valve B
1) Turn off he elec rical power and gas o he appliance.
2) Connec he manome er o gas valve es poin .
3) Wi h A, B closed open C and moni or manome er
over a 2 minu e period, a rise indica es a leak on valve
B.
To Check Valve A
1) Open C.
2) Open B o produce he main gas supply pressure
be ween A and B.
3) Close B
4) Sys em may be considered sound if over a period of
2 minu es any drop in pressure is less han 0.5 mbar
(0.2" wg.).
NOTE: Allow a manome er s abilisa ion period of
approxima ely 1-minu e before each 2 minu e check
period. Following soundness es s close valve B and
remove manome er connec ions and igh en es poin s.
Figure No. 3 - Gas Valve leak check procedure
Note: - Main gas supply pressure; G20 – 20mbar
G31 – 37mbar
6.0 FL E SYSTEM
De ailed recommenda ions for flue sys ems are given in
BS 6644, Bri ish Gas Publica ion IM/11, “Flues for
Commercial and Indus rial Gas-Fired Boilers and Air
Hea ers”.
The following no es are in ended o give general guidance
only.
6.1 General Requirements
The Hamwor hy Purewell series of boilers are designed
o be used wi h na ural draugh flues. Flue sys ems
should be designed in accordance
wi h curren regula ions and wi h reference o he Bri ish
Gas publica ion IM/11 “Flues for Commercial and
Indus rial Gas Fired Boilers and Air Hea ers”. The
following poin s should be no ed: -
1) Each boiler M ST have i s correc draugh diver er
fi ed in an unmodified condi ion before connec ion o
he flue sys em.
2) The bo om of he flue header should be a leas 500
mm above he draugh diver er skir bo om.
3) The flue sys em mus be self-suppor ing in he correc
posi ion o avoid compression of he draugh diver er
and enable i s removal for boiler cleaning.
4) Boilers should be loca ed as near he chimney as
possible he neares being no more han 2m (6f ) away.
5) The flue sys em should be designed o achieve a
nega ive suc ion a all imes a he draugh diver er ou le
on all modules in a bank. For op imum performance,
draugh condi ions should be be ween -0.05 o -0.125
mbar. In he case of a single boiler ins alla ion he
minimum ver ical flue heigh is 2m above he draugh
diver er skir . For mul iple boiler ins alla ions consul
Hamwor hy Hea ing Technical Depar men . In some
ins ances, mechanical assis ance may be necessary.
The boilers are sui able for connec ion o a fan dilu ed
flue sys em, refer o Bri ish Gas publica ion IM/11 “Flues
for Commercial and Indus rial Gas Fired Boilers and
Air Hea ers”.
6) Purewell boilers are sui able for ins alla ion in a
balanced compar men in accordance wi h he
requiremen s of BS 6644. Consul Hamwor hy Hea ing
Technical Depar men for help or assis ance if in doub .
6.2 Design Waste Gas Volume and Temperature
I is recommended ha he volume and empera ure of
he was e gases used for design of he flue sys em be
as shown in Figure No. 1.
6.3 Flue Condensation
Care should be aken o ensure ha he flue is ins alled
in such a way ha any condensa ion produced on s ar
up will drain away na urally.
6.4 Materials
Ma erials used for he flue sys em mus be mechanically
robus , resis an o in ernal and ex ernal corrosion, non-
combus ible and durable under he condi ions o which
hey are likely o be subjec ed.
6.5 Disconnection
Draugh diver er models are designed o enable he
primary flue o be lif ed clear of he boiler o ease
disconnec ion. The flue mus be correc ly reconnec ed
when servicing is comple e ensuring loca ing bol s are
securely fi ed. See Section 13: SERVICING for fur her
informa ion.

HAMWORTHY HEATING LTD. PUREWELL AUTOMATIC IGNITION 500001035/G
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6.6 Flue Discharge
The flue sys em mus ensure safe and efficien
opera ion of he boiler o which i is a ached, pro ec
he combus ion process from wind effec s and
disperse he produc s of combus ion o he ex ernal
air.
The flue mus ermina e in a freely exposed posi ion
and be so si ua ed as o preven he produc s of
combus ion en ering any opening in a building.
Where he flue diame er is less han 200mm (8") a
erminal mus be fi ed. Where he flue is of a larger
size considera ion should be given o he fi ing of a
flue discharge erminal or grill o s op ingress of birds,
e c.
6.7 Surface Temperatures
Combus ible ma erials in he vicini y of he boiler and
flue shall no exceed 65°C during boiler opera ion.
The flue shall no be closer han 50mm o any
combus ible ma erial, excep where i passes hrough
such ma erial wi h a non-combus ible sleeve when
he air gap may no be less han 25mm.
6.8 Flue System Location
The flue sys em mus no be placed or fi ed where
here is undue risk of acciden al damage o he flue
pipe or undue danger o persons in he vicini y.
NOTE! The flue M ST be self-suppor ing. Check
ha he flue and chimney are clear from any
obs ruc ion.
7.0 AIR S PPLY
De ailed recommenda ions for air supply are given in
BS 6644. The following no es are in ended o give
general guidance. In all cases here mus be provision
for an adequa e supply of air for bo h combus ion and
general ven ila ion, in addi ion o ha required for any
o her appliance.
7.1 Air Supply by Natural Ventilation
The boiler room mus have, or be provided wi h,
permanen air ven s direc ly o he ou side air, a
high level and a low level. For an exposed boiler
house, air ven s should be fi ed preferably on all
four sides, bu a leas on wo sides. Air ven s
should have negligible resis ance and mus no be
si ed in any posi ion where hey are likely o be
easily blocked or flooded or in any posi ion adjacen
o an ex rac ion sys em which is carrying flammable
vapour. Grilles or louvres mus be so designed ha
high veloci y air s reams do no occur wi hin he
space housing he boiler.
The air supplied for boiler house ven ila ion shall be
such ha he maximum empera ures wi hin he boiler
house shall be as follows:
1) A floor level (or 100mm above) = 25°C.
2) A mid-level (1.5m above floor level) = 32°C.
3) A ceiling level (or 100mm below) = 40°C.
Where bo h low and high level openings are used,
he grilles shall have a o al minimum free area of: -
Low Level (inle ): 540cm2 plus 4.5cm2 per Kilowa in
excess of 60kW o al ra ed inpu .
High Level (ou le ): 270cm2 plus 2.25cm2 per Kilowa
in excess of 60kW o al ra ed inpu .
Figure No 4 - Mechanical Ventilation Flow Rates
7.2 Air Supply by Mechanical Ventilation
Air supplied o he boiler room by Mechanical means
should be as follows: -
1) Mechanical inle and mechanical ex rac can be
u ilised providing design ex rac ion ra e does no
exceed one hird of he design inle ra e.
2) Mechanical ex rac ven ila ion wi h na ural inle
ven ila ion M ST NOT be used.
NOTE: For Mechanical ven ila ion sys ems an
au oma ic con rol should be provided o cu off he
gas supply o he boiler, in he even of failure of air
flow in ei her inle or ex rac fans.

HAMWORTHY HEATING LTD. PUREWELL AUTOMATIC IGNITION 500001035/G
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8.0 WATER CIRC LATION SYSTEM
8.1 General
The Purewell Cas Iron Boiler has a low wa er con en
and he requiremen s of minimum wa er flow are given
in Section 8.8: Minimum Water Flow Rates and
Figure No. 2. Recommenda ions for he wa er
circula ion sys em are given in BS 6644 and CP 342.
The following no es are of par icular impor ance: -
1) In a combined cen ral hea ing and ho wa er sys em,
he ho wa er s orage vessel mus be of he indirec
cylinder or calorifier ype. The ho wa er s orage vessel
should be insula ed preferably wi h no less han 75mm
(3 in) hick mineral fibre, or i s hermal equivalen .
2) Circula ing pipework no forming par of he useful
hea ing surface should be insula ed o help preven
hea loss and possible freezing, par icularly where
pipes are run hrough roof spaces and ven ila ed
cavi ies. Cis erns si ua ed in areas, which may be
exposed o freezing condi ions, should also be
insula ed. Insula ion exposed o he wea her should
be rendered wa erproof.
3) Draining aps mus be loca ed in accessible
posi ions which permi he draining of he whole
sys em, including he boiler and ho wa er s orage
vessel.
4) Each boiler has one 2" BSP female flow and one
2" BSP female re urn apping. Flow and re urn
headers should connec boilers bu sufficien leng h
of connec ing pipe should be allowed o clear he
casing before connec ing in o he headers. The
headers should be connec ed o he sys em in a
“reverse re urn” arrangemen ( he wa er flow in each
header is in he same direc ion) o ensure equal flow
in each module. Figure No. 8 shows ypical layou .
8.2 Pressure Relief Valve (Safety Valve)
Each boiler, or in he case of a modular ins alla ions,
each bank of boilers, mus be fi ed wi h a pressure
relief valve o BS 759 or BS 6759 Par 1(ISO 4126)
and sized as shown in BS 6644.
BS 6644 provides comprehensive informa ion for he
selec ion and loca ion of safe y valves and a en ion
is drawn o he higher capaci y requiremen s of safe y
valves for pressurised ho wa er sys ems.
8.3 Open Vent and Cold Feed Pipe
(See BS 6644 for fur her informa ion.)
Every boiler or group of boilers should have an open
ven pipe and cold feed pipe ins alled be ween he
boiler and he firs wa er isola ing valve. The minimum
bore (mm) of hese pipes per ins alla ion is as follows:-
The ven pipe mus rise con inually, i mus no be
valved excep by a design which when closed for
main enance ensures he boiler is open o
a mosphere. The pipe shall be pro ec ed agains
freezing where his migh occur.
8.4 Altitude Gauge (Water Pressure Gauge)
Every boiler or group of boilers should be provided
wi h a gauge comple e wi h isola ing cock. See Figure
No. 8 for ypical posi ion.
8.5 Thermometer
See Figure No. 8 for ypical posi ion. A hermome er
comple e wi h pocke should be fi ed in he pipework
o indica e wa er flow empera ure.
8.6 Drain Valves
Each boiler should have a 1/2” NB drain valve (no
H.H.L. supply) fi ed o drain he boiler only. The
hea ing sys em in o al should have drain valves as
recommended by BS 6644. See Figure No. 8 for
recommended posi ions.
8.7 Circulating Pump
One or more circula ing pumps will be required o
circula e wa er around he boilers and hea ing sys em.
Figure No. 1 shows he hydraulic resis ance of he
boiler. The pump should be si ed o facili a e servicing.
I is impor an o no e ha when Purewell boilers are
used o replace boilers on an exis ing sys em, he
pumps should be checked for performance agains
he new boiler wa erside pressure drop o ensure ha
he minimum flow ra e can be ob ained. I is also
impor an ha he exis ing sys em be flushed hrough
wice o remove any loose ma er, which may have
accumula ed. If in any doub regarding he cleanliness
of he sys em, a coarse fil er should be fi ed in he
re urn pipework o he boilers.
8.8 Minimum Water Flow Rates
Minimum wa er flow ra es are shown in Figure No. 2.
These flow ra es should be main ained hrough he
boiler a all imes whils he boiler is firing. If he wa er
flow ra e is allowed o fall below he minimum, he
boiler hea exchanger could fail due o he resul an
scale forma ion. Par icular a en ion should be paid
o he res ric ion of ex ernal flow circui s during periods
of low hea demand.

HAMWORTHY HEATING LTD. PUREWELL AUTOMATIC IGNITION 500001035/G
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8.9 Water Pressure Drop
The wa erside hydraulic resis ance (Pressure drop) is
shown in Figure Nos. 1 & 2.
NOTE: If boilers are run off ime clock con rol, a pump
overrun (no H.H.L. supply) should be fi ed which mus
run for a minimum of 5 minu es on shu -down of he las
boiler.
8.10 Control Schemes
8.10.1 Temperature Controls
An adjus able con rol hermos a is supplied for each
boiler and should be se o opera e wi hin he range 65-
90°C for s andard applica ions.
If a higher wa er empera ure is required (and providing
sufficien head on he wa er sys em is available) he
hermos a may be adjus ed o opera e up o 100°C. A
empera ure limi er, (hand rese limi hermos a ) is also
fi ed o he boiler and is normally se a 100°C. The
minimum difference be ween con rol hermos a and
empera ure limi er M ST NOT be less han 10°C.
8.10.2 Water Flow Controls
Any ex ernal mixing valves or similar con rols should
ALWAYS ensure ha he minimum wa er flow ra e shown
in Figure No. 2 is main ained.
8.10.3 Frost Protection
Considera ion should be given o fi ing a fros hermos a
se a approxima ely 4°C
8.11 nvented Pressurised Systems
See Figure No. 8 for ypical layou of a pressurised (Un-
ven ed) Ho Wa er Sys em.
In order o correc ly size a pressurisa ion uni for any
hea ing sys em cer ain parame ers are required. These
are: -
1) S a ic heigh of highes componen in sys em.
2) Sys em volume - if no known a general rule of humb
of 10 li res/kW ins alled boiler power can be used.
3) Maximum flow empera ure, i.e. mos sys ems run a
82°C.
4) Maximum sys em ho working pressure, generally given
in barg.
From he above informa ion Hamwor hy Hea ing can size
he pressure uni and also he expansion vessel required.
Care mus be aken in sizing expansion vessels o ensure
maximum accep ance fac ors are no exceeded. Normally
manufac urers of vessels impose a limi of 0.5. This value
mus no be exceeded a any ime during he opera ion
of he boiler: his includes he over pressure condi ion
should a safe y valve lif .
Considera ion should also be given o sizing of he safe y
valve(s) in he sys em. See BS 6759: Par 1 (ISO 4126)
for informa ion.
See also BS 6880: Par 1 for design considera ions.
8.12 Modular Boiler Control Schemes
For Modular applica ions Hamwor hy Hea ing can supply
a unique boiler managemen con rol sys em called he
‘Marshall’. This sys em comprises: a mas er con rol uni ,
which houses he main in erface processor and,
dependen on he number of boilers, a slave uni for each
of he o her boilers. Each uni plugs in o he previous
one by a low vol age signal wire. All he sensors are
connec ed o he las ‘slave’ by a single cable, which is
simple o a ach. Bo h mas er and slave(s) are
incorpora ed in o he con rol fascia for ease of
applica ion. For fur her informa ion con ac Hamwor hy
Hea ing for de ails.
9.0 ELECTRICAL S PPLY
WARNING: THIS APPLIANCE M ST BE EARTHED.
Wiring ex ernal o he boiler mus be ins alled in
accordance wi h he IEE Regula ions and any local
regula ions, which apply. Wiring mus be comple ed in
hea resis an 3-core cable. (Size 1.0mm2 csa). Boilers
are normally supplied sui able for 230 vol s, 50Hz.
Fascia fuse ra ing is 2A. Ex ernal fuses should be 6A
for all single boiler sizes.
The me hod of connec ion o he mains elec rici y supply
mus facili a e comple e elec rical isola ion of he single
boiler/ba ery wi h a con ac separa ion of a leas 3mm
in all poles.
This appliance must be isolated from the mains
electricity supply in the event of electric arc welding
being carried out on any connecting pipework.
A mains isola or mus be provided adjacen o he boiler
in a readily accessible posi ion. The supply should only
serve he boiler. NOTE! Vol free con ac elec rical
supplies mus also be isola ed when fi ed (see no e on
fascia). Fur her de ails regarding connec ion o he
elec rici y supply are given in BS EN 60335, Part 1 or
BS 3456, Part 201. The power supply should no be
swi ched by a ime clock, especially if a single header
pump ki is u ilised. The Purewell boiler has a remo e
s op/s ar loop which can be used o opera e he boiler(s)
under a imed regime. This remo e loop requires a vol
free con ac for opera ion. Power is supplied by he boiler
for his circui o func ion. The vol age will herefore be
he same as he boiler’s power supply. Refer o Figure
No. 10 for ypical si e wiring connec ions. See BS 6644
for fur her informa ion. Do no modify his circui in any
way. See Figure No. 12 for no e re: Ex ernal wiring.

HAMWORTHY HEATING LTD. PUREWELL AUTOMATIC IGNITION 500001035/G
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9.1 Site Wiring
Access o he con rols is achieved by ro a ing he 1/4 urn
la ch and removing he door. A 20mm dia. knockou is
provided in each side panel if required for elec rical
connec ions. Any o her rou ing of si e cables should
ensure ha cables do no pass close o he boiler flue
hood or ha any cable runking does no in erfere wi h
normal air circula ion and supply duc s.
A gland pla e is supplied wi h every Purewell boiler having
wo 20mm dia. holes for elec rical cable anchorage. A
plug and socke arrangemen is u ilised for he si e
erminal connec ions. Care mus be aken o ensure
correc connec ions are made o he relevan erminals
before applying power.
Refer o Figure Nos. 13 & 13a for ypical wiring diagrams
of s andard fully au oma ic boiler.
10.0 BOILER ASSEMBLY AND INSTALLATION
10.1 General
Each boiler is despa ched o si e as follows: -
i) Hea exchanger & baske including burners
and gas valve(s) e c. on a palle .
ii) Casing comple e wi h assembly ins ruc ions.
iii) Con rol assembly wi h relevan con rol sys em.
iv) Primary flue & draugh diver er. (Draugh Diver er
models only)
Fur her de ails of each individual assembly are given
below: -
1) Fac ory es ed hea exchanger cas ing assembly
comple e, including insula ion wrap, gas valve assembly
including pre-wired plug assembly. The gas connec ion
pipe should be fi ed o he boiler flue hood once he
hea exchanger is in place. NOTE! Care mus be aken
o ensure no damage occurs o ei her insula ion wrap or
gas connec ing pipe. THIS PIPE M ST NOT BE SED
TO MANOE VRE OR POSITION THE BOILER. NOTE!
Considera ion mus be given o he weigh of he boiler
(See Figure No. 9), before lif ing. I is recommended
ha he boiler is moved comple e wi h palle and
posi ioned correc ly. The palle can hen be disman led
and he boiler slid in o posi ion.
2) Casing including all screws, fas eners e c. o permi
si e assembly. Ins ruc ions are included in each box o
show me hod of assembly. Two sizes are manufac ured
hese are: - Small casing for boilers up o 80kW (NOTE!
P70 L/L u ilises larger casing), large casing for boilers
from 95kW o 120kW. NOTE! When ins alling a mul i-
casing se he spacing pla es mus be used o correc ly
space he boilers approx. 3mm apar prior o fi ing he
casing. (See label a ached o he baske fixing.)
I is recommended ha all mechanical work is carried
ou prior o fi ing he casing assembly, his will reduce
possible damage o he panels.
The casing assembly includes a componen lis , which
is also shown in Figure No. 7. You should check o
ensure ha all par s are supplied prior o assembly.
3) Con rols assembly including fascia panel and
hermos a s. This assembly will be sui ed o he
desired con rols and include any op ional ex ras
required. Refer o Figure No. 7 for fi ing ins ruc ions.
Ensure all hermos a capillaries are inser ed and
correc ly loca ed in o he op of he boiler. The con rols
assembly also incorpora es a socke which ma ches
he gas valve wiring plug. Care mus be aken o
ensure bo h plug and socke are correc ly loca ed and
fixed in posi ion by he screws provided.
4) (Standard Diverter models only) Primary flue pipe
and draugh diver er comple e wi h casing bezel.
Ins ruc ions are supplied wi h he draugh diver er on
how o assemble he uni , if required. These
ins ruc ions M ST be followed correc ly and fully
complied wi h o ensure correc opera ion.
NOTE! Ensure he baffle (No fi ed o 120kW boiler)
is posi ioned correc ly and laying fla on he hea
exchanger before fi ing he flue hood on o he boiler
(if removed).
10.2 Heat Exchanger Insulation Fitting Instructions
Wi h reference o Figure No. 5a - Unfold blanke and
offer up o he boiler as shown. Ensure gas pipe cu ou
is posi ioned o he lef and ha he ‘pe als’ are
uppermos . Si he insula ion blanke on o he baske
ensuring a snug fi .

HAMWORTHY HEATING LTD. PUREWELL AUTOMATIC IGNITION 500001035/G
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Figure No. 5a
Reference o Figure No. 5c - Fold down pe als as
shown. Use foil ape o affix edges. Fold as
Reference o Figure No. 5b - Insula ion should be
folded around boiler such ha i s rear edges mee in
he cen re. Ensure flow and re urn connec ions are
clear and unobs ruc ed. Apply foil ape down join.
Figure No. 5b
required. Ensure gas pipe bracke is clear and
unobs ruc ed.
Figure No. 5c
Ensure combus ion air passages are unobs ruc ed
when fully fi ed.
10.3 Gas Pipe Fitting Instructions
Wi h reference o Figure No. 6a - Remove half union
and gas valve from gas rain. Ensure gas valve/
manifold bracke does no suffer undue s ress/
movemen . Affix half union and gas valve assembly
o gas pipe as shown using proprie ary sealing
compound. Ensure gas valve lever is correc ly
orien a ed. Offer gas pipe o boiler as shown. Bracke
should be moun ed as shown. Bracke ’s posi ion will
be dependen on boiler size.
Figure No. 6a

HAMWORTHY HEATING LTD. PUREWELL AUTOMATIC IGNITION 500001035/G
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Figure No. 6b shows he pipe clamp fi ed o Purewell
60, 70, 80 and 120 kW boilers.
Figure No. 6b
Figure No. 6c shows he pipe clamp fi ed o Purewell
40, 50, 95 and 105 kW boilers.
Figure No. 6c
Tigh en screws ensuring ‘U’ clamp hreads do no
damage insula ion. I may be necessary o remove
he bo om hread of he ‘U’ clamp wi h he bracke in
lower posi ion as i may foul he draugh hood. Ensure
no undue s ress is placed on he gas pipe/manifold
and ensure pipe is ver ical/horizon al before clamping
in posi ion.
10.4 Connection of Boilers to the Flue System.
No es on he recommenda ion for design of he flue
sys em are given in Section 6:FL E SYSTEM.
10.4.1 Standard Diverter models: -
When supplied wi h a draugh diver er, i mus be
fi ed o he boiler as supplied, NO modifica ions are
permi ed on si e. Prior o fi ing he assembly o he
boiler, he op casing panel should be removed from
i s packing and placed in posi ion. Fi ing his panel
af er he flue is fi ed is no recommended. Care
should be aken o ensure he seal be ween primary
flue pipe and boiler spigo is sound as a leak may
affec he boilers’ opera ion.
10.4.2 Low Line models: -
The Low Line model incorpora es i s own draugh
diver er and care mus aken o ensure he seal
be ween he ou le spigo and flue pipe is sound o
avoid he escape of flue gas.
10.2.3 The op panel will require pro ec ing o ensure
no damage occurs o he plas ic coa ing during
subsequen si e assembly of o her componen s. I is
impor an , for service requiremen s, ha he flue
sys em is fully self-suppor ing. Check he flue and
chimney are clear from obs ruc ion.
10.5 Gas Connection
The Purewell boiler is supplied wi h a gas pipe which
when assembled exi s he casing a he rear, see
Figure No. 9 for posi ion. The incoming mains gas
supply mus be capable of supplying gas o he boiler
a he required pressure, under all firing condi ions.
For sizing informa ion see Figure No. 11. An approved
isola ing valve & union should be ins alled for each
boiler in a convenien and safe posi ion and be clearly
marked.
10.6 Water Connections
See Figure No. 9 for posi ion of wa er connec ions
(flow and re urn). A 1/2” BSP plug is fi ed local o he
re urn connec ion for he fi ing of a drain cock, NOTE!
(No HHL supply). Care mus be aken when ins alling
wa er sys em pipework ha undue s ress is avoided
on he boiler flow and re urn connec ions. I is
recommended ha unions are fi ed local o he boiler
o permi fu ure servicing requiremen s.
Fully closing valves mus no be connec ed o bo h
flow and re urn pipes unless he boiler is fi ed wi h an
individual, correc ly sized safe y valve. I is
recommended ha a 3-way ‘L’ por valve is fi ed in
he flow connec ion o allow an open ven si ua ion
should he boiler need o be fully isola ed from he
sys em.
10.7 Casing and Controls Assembly
For assembly of casing componen s and con rols uni
see Figure No. 7.

HAMWORTHY HEATING LTD. PUREWELL AUTOMATIC IGNITION 500001035/G
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Figure No. 7 - Assembling the Casing/Multi-Casing Set.
Multi-casing.
Note: Where boilers are in Modular form, i.e. MP360
(3 x 120kW), a mul i-casing pack is provided for each
addi ional boiler. For example: a riple boiler module
will require: - 1 off single casing pack plus 2 off mul i-
casing packs. If he suppor bar (bo om rail of i em
22) has no been pre-assembled, he following
procedure mus be aken: -
1) Loosen he nu s ha clamp he boilers oge her, (1
fron and 1 rear). Remove he bol , spacer and nu
assembly.
2) Posi ion he suppor bar (i em 22) be ween he boiler
baske s. Assemble using he “pozi-pan head” screws
(i em 13) and M6 nu s (i em 3).
3) Selec he remainder of i em 22: fron , op, and rear
bars and fi he ‘U‘ nu s (10 off i em 4), he la ch (2 off
i em 2) and door loca ion bracke s (2 off i em 7). The
rear member uses 6 off ‘U‘ nu s (4 off in he wo lower
pairs of holes and 2 off in he angle bracke a he
op).
Assemble he frame using he No 8 self- apping
screws (i em 5), he M6 pan head screws and washers
(i ems 12 and 13).
Single and multi-casings.
4) Selec he bo h side panels (i ems 17 & 18) and fi
he la ches (i em 2), ‘U‘ nu s (i em 4) and loca ion
bracke s (i em 7) as shown opposi e.
NOTE ! * = Single casing set ** = Multi casing set # = Lowline only
5) A ach side panels o he baske using i ems 3, 12,
13 and 14. A ach back panel. DO NOT F LLY
TIGHTEN SCREWS.
6) Loca e he con rol panel, and fi using No. 8 x 1/2”
self apping screws (i em 5).
7) Loca e he op panel and fi he s rikers (i em 2)
NOTE! L/L fi all four, D/D wo a rear only. Ensure he
blade is fi ed as shown. Fi he ‘U‘ nu s o he op
panel. Place he op panel in posi ion and pass he
draugh diver er hrough o loca e in o boiler spigo . Fi
he draugh diver er in o he boiler hood spigo and
ensure a comple e seal is made be ween hood and
diver er. For Low Line models he flue is connec ed
direc ly in o he boiler spigo . Ensure he seal is made
be ween flue pipe and spigo . Refer o section 10.2:
Connection of Boilers to the Flue System for fur her
informa ion. Wi h he flue correc ly fi ed, lower he op
panel and press he la ch and s rikers oge her and
secure a he fron wi h 2 off No. 8 self apping screws
(i em 5) hrough he con rol panel op edge.
8) Tigh en he back panel screws (i em 5) and fi screw
covers (par of i em 14) o i em 13 on side panels.
9) A ach he loca ion pins (i em 8) o he wo holes in
he 25mm re urn on he door by using M4 x 20 pan
head screws (i em 9), washers (i em 11) and nu s (i em
10). To fi he door, loca e he slo ed holes in he bo om
on o he loca ion bracke s (i em 7). Close he door
agains he con rol panel fascia ensuring he loca ing
pins en er he holes. Turn he 1/2 urn la ch in he cen re
of he door o lock.

HAMWORTHY HEATING LTD. PUREWELL AUTOMATIC IGNITION 500001035/G
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Figure No. 7a - Exploded View of Casing Set.

HAMWORTHY HEATING LTD. PUREWELL AUTOMATIC IGNITION 500001035/G
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11.0 COMMISSIONING AND TESTING
11.1 Electrical Installation
A sui ably compe en person MUST check wiring. Normal
supply required is 230 vol s AC, single phase, 50 Hz. An
isola or correc ly fused a 6A should be si ed close o he
boiler.
Access o he con rols is achieved by ro a ing he _ urn
la ch and removing he door. Connec ions o he boiler
should pass hrough he 2 x 20mm wiring gland pla e. If a
single header pump ki is used hen his power source
mus be cons an and no swi ched by any ime clock. The
boiler is supplied wi h a remo e s op/s ar circui for ime
clock opera ion. Any other interlocks, i.e.
Pressurisation unit, BEM System should be wired in
series with the remote stop/start loop.
The si e wiring erminal rail is marked wi h Live, Neu ral
and Ear h connec ions. See Figure No.10 for de ails.
IMPORTANT READ THE WARNING NOTE REGARDING
EXTERNAL VOLTAGES.
This rail is of he plug/socke ype and can be unplugged
for wiring if required.
Schema ics of he elec rical con rol circui (s) are shown in
Figure Nos. 13 & 13a.
11.2 Gas Installation
For design see Section 5:GAS S PPLY.
The whole of he gas ins alla ion including he me er mus
be inspec ed and es ed for soundness and purged in
accordance wi h he recommenda ions of BS 6891 or IM/
2 or IM/5 as appropria e.
11.3 Water Circulation System
For design see Section 8:WATER SYSTEM.
The sys em should be horoughly flushed ou wi h cold
wa er wi hou he pump in posi ion. Ensure all he valves
are open.
Wi h he pump fi ed he sys em should be filled and air
locks cleared. Ven he radia ors and check for leaks.
If he sys em is unven ed he pressurisa ion uni should
no be u ilised for he ini ial filling. This should be carried
ou using a WRC approved double check valve and
emporary-filling loop.
In order o comply wi h local Wa er Au hori y Regula ions,
his loop mus be disconnec ed when filling is comple e.
Wa er rea men s should no be fed hrough he
pressurisa ion uni unless permi ed by he manufac urer.
Check he expansion vessel cushion pressure as de ailed
by he manufac urer’s Ins aller’s Guide.
11.4 Commissioning the Boiler
Before a emp ing o commission any boiler, ensure ha
personnel involved are aware of wha ac ion is abou o
be aken and begin by making he following checks: -
1) Flueway passages o chimney are clear.
2a) Standard Diverter models: - If necessary, remove
he flue hood and baffle (no fi ed o he 120kW boiler)
o ensure he boiler flueways are clear. Reposi ion he
gas baffle ensuring ha i is laying fla on he op sec ion.
Re-fi he flue hood. Ensure boiler draugh diver er
passages are clear and clean.
2b) Low Line models: - The low line draugh diver er
incorpora es an in egral inspec ion cover. To gain access,
remove insula ion and M6 bol s on he sloping fron of
he hood assembly. This will reveal he inner par of he
boiler, if fur her access is required, remove primary flue
pipe (ensure i is correc ly suppor ed), and remove
comple e op of he draugh diver er assembly. Af er
cleaning he boiler re-assemble draugh diver er in
reverse of dis-assembly. Ensure all join s are correc ly
sealed.
3) Adequa e ven ila ion as per Section 7: Air Supply
exis s in he boiler house.
4) The sys em is fully charged wi h wa er, ready o receive
hea . All necessary valves are open and he pump is
circula ing wa er.
5) The pipework and valve arrangemen is ins alled o
Hamwor hy Hea ing recommenda ions in such a way ha
wa er flow ra es will be in accordance wi h Figure No. 1.
6) The gas supply pipework is clear of any loose ma er,
es ed for soundness and purged o CP: 331/3.
11.5 Boiler Checks Prior To Lighting
NOTE! Refer o Figure No. 1 for maximum gas inle
pressure for normal opera ion. Informa ion rela ing o
propane firing can be found in Appendix ‘A’.
Note: - All propane boilers are fi ed wi h a low gas
pressure swi ch (se a 20mbar). Should he gas supply
pressure fall below his level, he boiler will not opera e.
1) Gas supply is connec ed bu urned o he “off” posi ion.
Any unions or fi ings are correc ly igh ened, es poin s
are closed, burners correc ly posi ioned, injec ors are in
place (of correc size) and igh and ha he igni ion and
probe leads are connec ed correc ly. Ensure igni ion
assembly elec rodes are no cracked or broken.
2) Ensure elec rici y is connec ed and 2A fuse on boiler
removed, he plug/socke gas valve connec ion is
correc ly loca ed and fully igh ened wi h screws
provided and ha he hermos a bulbs are fully
inser ed in o he boiler pocke . Rese empera ure
limi er by firmly pressing pin (in con rols housing.)