Solfex Direct D90 User guide

Design, Installation,
User & Servicing
Instructions
An unvented hot water storage
appliance complying with the
requirements of Building Regulations
Approved Document G3 and
manufactured in accordance with
BS EN 12897,the specification for
unvented water storage vessels.
In the interest of continuously
improving the Duplex Unvented
Cylinder range,Solfex Limited reserve
the right to modify the product without
notice,and in these circumstances this
booklet,which is accurate at the time of
printing,should be disregarded.

Page 2
Section Page
DESIGN
Description 3
Technical Information 6
System Design 10
INSTALLATION
Installation 12
Commissioning 22
USER INSTRUCTIONS 23
SERVICING AND MAINTENANCE
Servicing and Maintenance 24
Fault Finding 25
Short Parts List 28
APPENDIX
Appendix A 29
Appendix B 30
Notes 31
BENCHMARK
Commissioning Checklist 32
Service Record 33
ISSUE 15: JAN 2012
These instructions should be read in conjunction with the installation/servicing
instructions issued by the manufacturer of the heat source being used.
Any installation must be in accordance with the relevant requirements of the Gas
SafetyRegulations,BuildingRegulations,I.E.E.WiringRegulationsandtheWaterFitting
Regulations (England and Wales) or Water Byelaws (Scotland). It should be read in
accordance with the relevant recommendations of the following:
BS 6798;BS 5549;BS 5546;
BS 5440:1;BS 5440:2;CP 331:3
BS 6700:BS 5258 and BS 7593:1992
SolfexUnvented Cylinder iscovered by Section G3of theBuilding Regulations (England
and Wales) Technical Standard P3 (Scotland) and Building Regulation P5 (Northern
Ireland).Compliancecan be achieved via a CompetentPersonSelf Certification Scheme
ornotificatonofinstallationtotheLocalAuthorityBuildingControlDepartment.
It must be installed by a competent person as defined by the relevant regulations.
Manufacturers notes must NOT be taken as over-riding statutory obligations.
This appliance is not intended for use by persons (including children) with reduced
physical,sensory or mental capabilities,or lack of experience and knowledge unless
they have been given supervision or instruction concerning use of the appliance by
a person responsible for their safety. Children should be supervised at all times to
ensure they do not play with the appliance.
This information is provided to assist generally in the selection of equipment.
Responsibility for selection and specification of our equipment must however remain
thatofourcustomerandanyexpertsorconsultantsconcernedwiththeinstallation(s).
Pleasenote:thatwedonotthereforeacceptanyresponsibilityformattersofdesign
selectionorspecification,fortheeffectivenessofaninstallationorsystemcontaining
one of our products unless specifically requested to do so in writing.
All goods aresold subject toour conditionsof sale whichare setout at therear ofthis
specification. In the interest of continuously improving the Solfex Unvented Cylinder
range, Solfex limited reserve the right to modify the product without notice, and in
these circumstances this booklet,which is accurate at the time of printing,should be
disregarded. An updated set of instructions will be produced and supplied with new
appliancesandwill bemade availableforotherappliances on request.
A KIWA product approved to comply with all relevant parts of the
Building Regulations and Water Supply (Water Fittings) Regulations.
Visitwww.kiwa.co.ukformore information.
SolfexUnvented Cylinder is produced under an ISO 9001:2008 Quality
Management System approved by BSI.
Benchmarkplacesresponsibilitiesonbothmanufacturersandinstallers.Thepurposeisto
ensure thatcustomers areprovidedwith thecorrect equipment for theirneeds,thatit is
installed,commissionedandservicedinaccordancewiththemanufacturersinstructions
by competent persons and that it meets the requirements of the appropriate Building
Regulations.The Benchmark Checklist can be used to demonstrate compliance with
BuildingRegulationsandshouldbeprovidedtothecustomerforfuturereference.
Installers are required to carry out installation, commissioning and servicing work
in accordance with the Benchmark Code of Practice which is available from the
Heating and Hot Water Industry Council who manage and promote the Scheme.
Visitwww.centralheating.co.uk formoreinformation.

Page 3
DESCRIPTION
DESIGN
Supplied By: Solfex Limited
Maximum inlet pressure to
Pressure reducing valve 12 bar
Operating pressure (PRV setting) 3 bar
Expansion vessel charge pressure 3 bar
Expansion relief valve setting 4.75 bar
Opening pressure of P &T Relief Valve 6 bar
Opening temperature of P &T ReliefValve 95°C
Energy cut-out thermostat setting 80°C
Max.working pressure - Primary heat exchanger (Indirect models) 6 bar
Max.working pressure - Solar heat exchanger (Solar models) 10 bar
Immersion heater rating 3kW,240V AC
All cylinders are manufactured in accordance with the requirements of EN12897.
Thetundishmust be positionedsothat itisvisible totheoccupant and isawayfrom
electrical devices.
Components supplied with Stainless Lite:
• Cold water inlet PRV combination valve/expansion relief
• Pressure and temperature relief valve
• Control thermostat
• Energy cut-out thermostat
• Energy cut-out motorised valve (indirects only)
• Tundish
• 3kW Immersion heater
• Expansion vessel/mounting bracket/flexible hose
• Technical/user product literature
(Note:Pleaserefertotables1and2onpages6-9toconfirmthequantityofimmersion
heaters supplied with the unit)
Inanysituationwherethevolumeofheatedpipework(eg.secondarycirculation
pipes or manifold pipework for multiple units) exceeds 10 litres, then an
additionalexpansionvesselmustbefittedtoaccommodatetheextraexpansion
volume.
Handling Before Installation
Solfex Unvented Cylinder must be handled with care and stored the correct way up
in a dry place. Any manual handling/lifting operations will need to comply with the
requirementsoftheManualHandlingOperationsRegulationsissuedbytheH.S.E.The
appliancecan be movedusing a sack truck on the rearface although careshould be
taken and the routeshould be even.In apartmentbuildings containinga numberof
storeyswewouldrecommendthattheappliancesaremovedverticallyinamechanical
lift.If it is proposed to use a crane,expert advice should be obtained regarding the
need for slings,lifting beams etc.
A specific manual handling assessment is shown in Appendix B at the rear of this
manual.
Maintenance
Modifications should not be made to this
product.Replacementparts,includingimmersion
heaters,shouldbepurchasedfromSolfexLimited,
oragentsapprovedbythem.Unventedhotwater
storagevesselsneedregularroutinechecks,and
thesearedetailedbelow. Itisforthisreasonthat
thismanualmustalwaysbeleftwiththeSolfex
Unvented Cylinder.
It is essential that these checks be carried out
atthetimeofboilermaintenancebyaqualified
installer:
1. Manuallyopenthereliefvalvesinturn,and
check that water is discharged from the
valves and runs freely through the tundish
andoutatthedischargepoint. Ensurethat
the valves re-seat satisfactorily.(Note - the
water may be very hot).
2. It is important to check that the discharge
pipework is carrying the water away
adequately.Check for blockages etc.if it is
not.
3. Turn the mains water off and remove and
clean the strainer element in the Pressure
ReducingValve.
4. Checkthechargepressureintheexpansion
vessel and repressurise if required
5. Re-fill the system and ensure that all relief
valves have re-seated.
6. The Benchmark Service Record should be
updated at each service.
7. Check thewater pressure downstream ofthe
combinationvalveis3barinstaticcondition.
8. Check and if necessary, descale the heat
exchanger in hard water areas ie. above
200ppm(mg/l).
Note:
Thecylinderisfactoryfittedwithatemperature
&pressurereliefvalvethatmustnotbeusedfor
any other purpose or removed.
The cylinder is factory fitted with immersion
heaters with thermal cut outs. Immersions
without thermal cut outs must not be fitted.

Page 4
DESIGN
DESCRIPTION
Solfex Unvented Cylinder is a range of unvented
hotwaterstoragecylinders,manufacturedinthe
latesthighqualityduplexstainlesssteel.Theyare
designed to provide mains pressure hot water
and are supplied as a package which complies
with Section G3 of the Building Regulations.The
appliance is extremely well insulated using high
densityHCFCfreefoaminsulationwithanozone
depleting potential (ODP) of zero and a global
warming potential (GWP) of 1. It is fitted with all
necessarysafetydevicesandsuppliedwithallthe
necessarycontroldevicestomakeinstallationon
siteaseasyaspossible.
SolfexUnventedCylinderisavailableinfour
basic variants:
1. Solfex Unvented Cylinder Direct - For
providing hot water heated by electricity
(Figure 1).
2. Solfex Unvented Cylinder Indirect
- For use with gas or oil boilers (Figure 2).
Unvented cylinders must not be used with
solid fuel boilers or steam as the energy
source.
3. Solfex Unvented Cylinder Direct Solar -
For providing hot water by solar gains and
electricity.(Figure 3).
4. Solfex Unvented Cylinder Indirect Solar
- For providing hot water by solar gains and
gasoroilboilers(Figure4).Unventedcylinders
must not be used with solid fuel boilers or
steamastheenergysource.
Solfex Unvented Cylinder DIRECT
SolfexUnventedCylinderdirectisanelectrically
heated, unvented hot water storage cylinder
designed primarily for use with off peak
electrical supplies.
It is supplied fitted with two 3kW immersion
heaters which are BEAB approved for safety as
recommended by the Electricity Council.
Solfex Unvented Cylinder direct models are
listed inTable 1 on Page 6 & 7.
SolfexUnventedCylinderINDIRECT
SolfexUnventedCylinderindirectisanunvented
hotwaterstoragecylinderandisprovidedwith
a high efficiency internal primary coil which is
designed for use with a gas or oil boiler and
is suitable for both open vented and sealed
pumped primary systems.
When used with a sealed heating system the
boilermustincorporateitsownenergycut-out
overheat thermostat.
Solfex Unvented Cylinder indirect models are
listed inTable 2 on Page 8 & 9.
Solfex Unvented Cylinder
DIRECT Solfex Unvented Cylinder INDIRECT
Figure 1 Figure 2
Pipework is not supplied by manufacturer,
but to be supplied and fitted by installer.

Page 5
DESIGN
DESCRIPTION
Solfex Unvented Cylinder DIRECT SOLAR
SolfexUnventedCylinderdirectisanelectrically
heated, unvented hot water storage cylinder
designed primarily for use with off peak
electrical supplies.
It is supplied fitted with two 3kW immersion
heaters which are BEAB approved for safety as
recommended by the Electricity Council.
Ahigh efficiency coilis positionedin the lower
part of the Solfex Unvented Cylinder vessel to
ensure maximum benefit of solar gain energy.
Solfex Unvented Cylinder direct models are
listed inTable 1 on Page 6 & 7.
Solfex Unvented Cylinder INDIRECT SOLAR
SolfexUnventedCylinderindirectisanunvented
hotwaterstoragecylinderandisprovidedwith
a high efficiency internal primary coil which is
designed for use with a gas or oil boiler and
is suitable for both open vented and sealed
pumped primary systems.
When used with a sealed heating system the
boilermustincorporateitsownenergycut-out
overheat thermostat.
Ahighefficiencysecondsolarcoilispositioned
below the primary coil to ensure maximum
benefit of solar gain energy.
Solfex Unvented Cylinder indirect models are
listed inTable 2 on Page 8 & 9.
Note:
The cold supply elbow c/w drain tapping
must be fitted as shown in figs 1,2,3 and 4.
Aflexiblehosecanthenbeconnectedtothe
drain tapping and, providing the hose runs
below the lowest level of the cylinder,then
allthewatercontentscanbedrainedout by
syphonic action. (The cold feed pipe dips
internally to the base of the cylinder.)
Solfex Unvented Cylinder
DIRECT SOLAR Solfex Unvented Cylinder INDIRECT SOLAR
Figure 3 Figure 4
Pipework is not supplied by manufacturer,
but to be supplied and fitted by installer.

Page 6
DESIGN
TECHNICAL INFORMATION - DIRECT MODELS
Table 1
Model
Weight - Empty
Weight - Full
Capacity (TotalVolume)
Pressure Regulator 3 bar inlet
group c/w balance cold supply,
expansion vessel connection and
expansion valve set at 4.75 bar
ExpansionVessel size.
Pre-charged to 3 bar
Overall Height
Overall Diameter
Pressure &Temperature
ReliefValve 6bar 95°C
22mm Secondary
ReturnTapping
On Peak Immersion
Heater - High Level
Cold Feed 22mm
Compression Connection
Off Peak Immersion
Heater - Low Level
Volume of On PeakWater
Heated
Dual Control & Overheat Stat
kg kg Litres bar Litres A=mm mm B=mm C=mm D=mm E=mm F=mm Litres G=mm
Direct
D90 13 103 90 3 12 732 550 490 n/a n/a 367 223 n/a n/a
D120 18 138 120 3 12 920 550 678 n/a 487 367 223 55 n/a
D150 22 172 150 3 18 1107 550 865 n/a 587 442 223 70 n/a
D180 24 204 180 3 18 1295 550 1053 n/a 686 442 223 85 n/a
D210 28 238 210 3 24 1483 550 1241 1127 786 442 223 90 n/a
D250 32 282 250 3 24 1733 550 1491 1377 927 522 223 125 n/a
D300 37 337 300 3 35 2020 550 1777 1577 1077 522 223 155 n/a
D400 48 448 400 3 2x 24 2040 630 1784 1592 1181 457 238 180 n/a
Direct Slimline
D60-SL 13 73 60 3 12 704 475 462 n/a n/a 348 197 n/a n/a
D90-SL 16 106 90 3 12 976 475 734 n/a n/a 348 197 n/a n/a
D120-SL 22 142 120 3 12 1284 475 1006 n/a 650 348 197 55 n/a
D150-SL 30 180 150 3 18 1520 475 1278 n/a 785 423 197 70 n/a
D180-SL 31 211 180 3 18 1790 475 1548 n/a 921 423 197 85 n/a
D210-SL 32 242 210 3 24 2005 475 1763 1580 1147 503 197 90 n/a
Solar Direct
SOL180d 26 206 180 3 18 1295 550 1053 n/a 746 437 482 75 n/a
SOL210d 30 240 210 3 24 1483 550 1241 1127 908 437 544 80 n/a
SOL250d 34 284 250 3 24 1733 550 1491 1377 1092 522 629 100 n/a
SOL300d 39 339 300 3 35 2020 550 1777 1577 1287 522 724 115 n/a
SOL400d 49 449 400 3 2x 24 2040 630 1784 1592 1296 557 691 140 n/a
Solar Direct Slimline
SOL 180d-SL 32 212 180 3 18 1790 475 1548 n/a 1090 423 640 75 n/a
SOL 210d-SL 36 246 210 3 24 2005 475 1763 1589 1190 503 730 80 n/a
A
C
Direct
D
F
E
B
R
A
Solar Direct
C
N
M
L
P
E
K
B
D
F

Page 7
DESIGN
TECHNICAL INFORMATION - DIRECT MODELS
Extra Stat Pocket
For Boiler Use If Required
22mm Primary Return
Compression Connection
(28mm tails for 400 litre model)
22mm Primary Flow
Compression Connection
(28mm tails for 400 litre model)
22mm Solar Return
Compression Connection
22mm Solar Flow
Compression Connection
Dual Control & Overheat Stat
Solar Pocket Solar Pocket
Second Off Peak Immersion
Heater - Low Level
kW Rating of Primary Coil
Surface Area of
Primary Heater Coil
Pressure Loss Across
Primary Heater Coil
Surface Area of
Solar Heater Coil
Pressure Loss Across Solar
Heater Coil
Heat UpTime from 15°C to 60°C
(applies to Primary Heat Source only)
RecoveryTime after 70% Draw Off
(applies to Primary Heat Source only)
Standing Losses kWhr/24hr
Dedicated SolarVolume
H=mm I=mm J=mm K=mm L=mm M=mm N=mm P=mm R=mm kW m2bar m2bar min min kWh Litres
n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a 90 58 0.80 n/a
n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a 119 90 1.00 n/a
n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a 150 121 1.20 n/a
n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a 179 157 1.40 n/a
n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a 209 192 1.60 n/a
n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a 249 224 1.75 n/a
n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a 299 263 1.93 n/a
n/a n/a n/a n/a n/a n/a n/a n/a 338 n/a n/a n/a n/a n/a
398/198 358/179 3.33 n/a
n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a 60 39 0.95 n/a
n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a 90 58 1.25 n/a
n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a 119 90 1.52 n/a
n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a 150 121 1.77 n/a
n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a 179 157 2.01 n/a
n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a 209 192 2.23 n/a
n/a n/a n/a 223 352 419 882 203 n/a n/a n/a n/a 0.680 0.191 n/a 90 1.40 60
n/a n/a n/a 223 352 419 1000 203 n/a n/a n/a n/a 0.680 0.191 n/a 115 1.60 70
n/a n/a n/a 223 472 539 1180 262 n/a n/a n/a n/a 0.970 0.241 n/a 139 1.75 84
n/a n/a n/a 223 472 539 1367 262 n/a n/a n/a n/a 0.970 0.241 n/a 187 1.93 100
n/a n/a n/a 238 548 651 1383 334 n/a n/a n/a n/a 1.270 0.310 n/a 260 3.33 150
n/a n/a n/a 179 329 678 1263 243 n/a n/a n/a n/a 0.680 0.191 n/a 90 2.01 60
n/a n/a n/a 179 409 778 1363 273 n/a n/a n/a n/a 0.680 0.191 n/a 115 2.23 70
4
0
,0
0
º
4
5
,
00º
3
5
,00º
2
5,
0
0
º
1
5
,
0
0
º
NOTES
1. Not all models - see table 1.
2. Recovery times based on Primary
Coil/I.H.duty(ie.assumestheboiler
output is adequate).
3. All connections are supplied with
compression fittings for direct
connection to copper pipework.
4. The heat up times shown for
the D400 model indicate the
times when 1 or 2 immersions are
connected.
5. The diagrams shown are generic.
For exact product specification
refer to the table eg. the number
of immersion heaters varies
depending on model.
6. Heat up and recovery times based
on0.25l/sprimaryflowrateandat
82°C flow temperature.

Page 8
DESIGN
TECHNICAL INFORMATION - INDIRECT MODELS
Table 2
Model
Weight - Empty
Weight - Full
Capacity (TotalVolume)
Pressure Regulator 3 bar inlet
group c/w balance cold supply,
expansion vessel connection and
expansion valve set at 4.75 bar
ExpansionVessel size.
Pre-charged to 3 bar
Overall Height
Overall Diameter
Pressure &Temperature
ReliefValve 6bar 95°C
22mm Secondary
ReturnTapping
On Peak Immersion
Heater - High Level
Cold Feed 22mm
Compression Connection
Off Peak Immersion
Heater - Low Level
Volume of On PeakWater
Heated
Dual Control & Overheat Stat
kg kg Litres bar Litres A=mm mm B=mm C=mm D=mm E=mm F=mm Litres G=mm
Indirect
IND90 19 109 90 3 12 732 550 490 n/a 352 367 n/a 40 367
IND120 22 142 120 3 12 920 550 678 n/a 352 367 n/a 67 367
IND150 26 176 150 3 18 1107 550 865 n/a 392 442 n/a 92 407
IND180 28 208 180 3 18 1295 550 1053 n/a 432 442 n/a 116 447
IND210 33 243 210 3 24 1483 550 1241 1127 432 442 n/a 145 482
IND250 38 288 250 3 24 1733 550 1491 1377 927 522 512 109 577
IND300 44 344 300 3 35 2020 550 1777 1577 1077 522 512 130 677
IND400 55 455 400 3 2x 24 2040 630 1777 1577 1151 542 586 180 668
Indirect Slimline
IND60-SL 14 74 60 3 12 704 475 462 n/a 352 348 n/a 28 242
IND90-SL 19 109 90 3 12 976 475 734 n/a 392 348 n/a 54 359
IND120-SL 23 143 120 3 12 1248 475 1006 n/a 432 348 n/a 75 423
IND150-SL 28 178 150 3 18 1520 475 1278 n/a 462 423 n/a 102 514
IND180-SL 31 211 180 3 18 1790 475 1548 n/a 512 503 n/a 125 604
IND210-SL 34 244 210 3 24 2005 475 1763 1589 512 503 n/a 150 695
Solar Indirect
SOL180i 30 210 180 3 18 1295 550 1053 n/a 574 437 n/a 80 747
SOL210i 35 245 210 3 24 1483 550 1241 1127 614 437 n/a 95 867
SOL250i 40 290 250 3 24 1733 550 1491 1377 1042 522 n/a 115 994
SOL300i 46 346 300 3 35 2020 550 1777 1577 1155 522 n/a 140 1130
SOL400i 59 459 400 3 2 x 24 2040 630 1792 1592 1129 557 n/a 190 1053
Solar Indirect Slimline
SOL180i-SL 33 213 180 3 18 1790 475 1548 n/a 1044 423 n/a 75 897
SOL210i-SL 37 247 210 3 24 2005 475 1763 1589 1130 503 n/a 85 1083
A
C
Indirect
D
H
F
E
I
J
B
G
D
Solar Indirect
N
G
P
I
E
K
J
A
B
M
L
C

Page 9
DESIGN
TECHNICAL INFORMATION - INDIRECT MODELS
Extra Stat Pocket
For Boiler Use If Required
22mm Primary Return
Compression Connection
(28mm tails for 400 litre model)
22mm Primary Flow
Compression Connection
(28mm tails for 400 litre model)
22mm Solar Return
Compression Connection
22mm Solar Flow
Compression Connection
Dual Control & Overheat Stat
Solar Pocket Solar Pocket
Second Off Peak Immersion
Heater - Low Level
kW Rating of Primary Coil
Surface Area of
Primary Heater Coil
Pressure Loss Across
Primary Heater Coil
Surface Area of
Solar Heater Coil
Pressure Loss Across Solar
Heater Coil
Heat UpTime from 15°C to 60°C
(applies to Primary Heat Source only)
RecoveryTime after 70% Draw Off
(applies to Primary Heat Source only)
Standing Losses kWhr/24hr
Dedicated SolarVolume
H=mm I=mm J=mm K=mm L=mm M=mm N=mm P=mm R=mm kW m2bar m2bar min min kWh Litres
367 223 312 n/a n/a n/a n/a n/a n/a 16.5 0.59 0.165 n/a n/a 21 16 0.80 n/a
367 223 312 n/a n/a n/a n/a n/a n/a 18 0.59 0.165 n/a n/a 27 19 1.00 n/a
407 223 392 n/a n/a n/a n/a n/a n/a 18.5 0.68 0.191 n/a n/a 28 19 1.20 n/a
447 223 392 n/a n/a n/a n/a n/a n/a 19 0.78 0.216 n/a n/a 33 21 1.40 n/a
482 223 392 n/a n/a n/a n/a n/a n/a 20.5 0.78 0.216 n/a n/a 41 26 1.60 n/a
577 223 472 n/a n/a n/a n/a n/a n/a 21.5 0.97 0.241 n/a n/a 44 30 1.75 n/a
677 223 522 n/a n/a n/a n/a n/a n/a 25 0.97 0.241 n/a n/a 48 32 1.93 n/a
668 223 533 n/a n/a n/a n/a n/a n/a 30.5 1.27 0.310 n/a n/a 55 36 3.33 n/a
242 179 329 n/a n/a n/a n/a n/a n/a 15 0.59 0.165 n/a n/a 14 11 0.95 n/a
359 179 329 n/a n/a n/a n/a n/a n/a 16.5 0.59 0.165 n/a n/a 21 16 1.25 n/a
423 179 329 n/a n/a n/a n/a n/a n/a 18 0.59 0.165 n/a n/a 27 19 1.52 n/a
514 179 409 n/a n/a n/a n/a n/a n/a 18.5 0.68 0.191 n/a n/a 28 19 1.77 n/a
604 179 449 n/a n/a n/a n/a n/a n/a 19.0 0.78 0.216 n/a n/a 33 21 2.01 n/a
695 179 449 n/a n/a n/a n/a n/a n/a 20.5 0.78 0.216 n/a n/a 41 26 2.23 n/a
n/a 614 834 223 352 419 882 218 n/a 18 0.59 0.165 0.680 0.191 28 16 1.40 96
n/a 654 914 223 352 419 1000 233 n/a 18.5 0.68 0.191 0.680 0.191 35 16 1.60 101
n/a 702 1002 223 472 539 1180 294 n/a 19 0.78 0.216 0.970 0.241 38 19 1.75 107
n/a 815 1115 223 472 539 1367 300 n/a 20.5 0.78 0.216 0.970 0.241 41 20 1.93 125
1053 766 1026 238 548 651 1383 357 n/a 22 0.97 0.241 1.270 0.310 45 24 3.33 165
n/a 619 1004 179 320 583 1232 243 n/a 18 0.59 0.165 0.680 0.191 28 16 2.01 60
n/a 710 1095 179 409 673 1383 273 n/a 18.5 0.68 0.191 0.680 0.191 35 16 2.23 70
4
0
,0
0
º
4
5
,
00º
3
5
,00º
2
5,
0
0
º
1
5
,
0
0
º
NOTES
1. Not all models - see table 2.
2. Recovery times based on Primary
Coil/I.H.duty(ie.assumestheboiler
output is adequate).
3. All connections are supplied with
compression fittings for direct
connection to copper pipework.
4. The diagrams shown are generic.
For exact product specification
refer to the table eg. the number
of immersion heaters varies
depending on model.
5. Heat up and recovery times based
on0.25l/sprimaryflowrateandat
82°C flow temperature.

Page 10
DESIGN
SYSTEM DETAILS
Solfex Unvented Cylinder Direct
Basic Appliance
1. Hot water draw off (22mm) compression
2. Temperature&pressurereliefvalve95°/6bar
3. Hot water secondary return 22mm
(not fitted to smaller sizes,see table 1)
4. Immersion heater 1¾”BSP 3kW
(normally on-peak)
5. 22mm cold supply compression
6. Immersion heater 1¾”BSP 3kW
(normally off-peak)
7. Immersion heater 1¾”BSP 3kW
(normally off-peak - 400 litre model only)
Component kit supplied separately
A. Combination inlet group incorporating
pressure reducing valve, strainer, check
valve,balancecoldtakeoffpoint,expansion
reliefvalveandexpansionvesselconnection
points.
B. Portableexpansionvesselsc/wflexiblehose
and wall bracket
C. Tundish
Solfex Unvented Cylinder Indirect
Basic Appliance
1. Hot water draw off (22mm) compression
2. Temperature&pressurereliefvalve95°/6bar
3. Hot water secondary return 22mm
(not fitted to smaller sizes,see table 2)
4. Immersion heater 1¾”BSP 3kW
5. 22mm cold supply compression
6. Immersion heater 1¾”BSP 3kW
7. Dual control/overheat stat pocket (22mm)
8. Boiler control sensor pocket (spare)
9. Primary return (22mm)
- (28mm tails for 400 litre models)
10. Primary flow (22mm)
- (28mm tails for 400 litre models)
Component kit supplied separately
A. Combination inlet group incorporating
pressure reducing valve, strainer, check
valve,balancecoldtakeoffpoint,expansion
reliefvalveandexpansionvesselconnection
points.
B. Potableexpansionvesselsc/wflexiblehose
and wall bracket
C. Tundish
D. Dual control thermostat and combined
overheat thermostat
E. Two port (22mm) zone valve for
primary circuit
F. Wiring junction box for primary system
1
2
3
4
7
5
6
9
8
10
Typical arrangement of component kit shown fitted to the appliance for clarity
Pipework to be supplied and fitted by installer.
1
2
5
3
4
6
7

Page 11
DESIGN
SYSTEM DETAILS
7
9
3
11
6
12
12
1
2
8
4
5
10
Solfex Unvented Cylinder Direct Solar
Basic Appliance
1. Hot water draw off (22mm) compression
2. Temperature&pressurereliefvalve95°/6bar
3. Hot water secondary return 22mm
(not fitted to smaller sizes,see table 1)
4. Immersion heater 1¾”BSP 3kW
(normally on-peak)
5. 22mm cold supply
6. Immersion heater 1¾”BSP 3kW
(normally off-peak)
7. Dual control/Overheat stat pocket
8. Solar coil return to panel collector (22mm)
compression
9. Solarcoilflow from panel(22mm) compression
10. Solar thermostat pocket
Component kit supplied separately
A. Combination inlet group incorporating
pressure reducing valve, strainer, check valve,
balance cold take off point, expansion relief
valveand expansion vesselconnectionpoints.
B. Portableexpansionvesselsc/wflexiblehose
and wall bracket
C. Tundish
D. Dual control thermostat and combined
overheat thermostat
Solfex Unvented Cylinder Indirect Solar
Basic Appliance
1. Hot water draw off (22mm) compression
2. Temperature&pressurereliefvalve95°/6bar
3. Hot water secondary return 22mm
(not fitted to smaller sizes,see table 2)
4. Immersion heater 1¾”BSP 3kW
5. 22mm cold supply
6. Dual control/Overheat stat pocket
7. Primary return (22mm)
- (28mm tails for 400 litre models)
8. Primary flow (22mm)
- (28mm tails for 400 litre models)
9. Dual control/Overheat stat pocket
10. Solar coil return to panel collector (22mm)
compression
11. Solarcoilflow from panel(22mm) compression
12. Solar thermostat pocket
Component kit supplied separately
A.
Combination inlet group incorporating
pressure reducing valve, strainer, check valve,
balance cold take off point, expansion relief
valveand expansion vesselconnectionpoints.
B. Potableexpansionvesselsc/wflexiblehose
and wall bracket
C. Tundish
D. Dual control thermostat and combined
overheat thermostat (x2)
E. Two port (22mm) zone valve for
primary circuit
F. Wiring junction box for primary system
1
2
5
8
7
6
4
3
9
10
10
Typical arrangement of component kit shown fitted to the appliance for clarity
Pipework to be supplied and fitted by installer.

Page 12
INSTALLATION
INSTALLATION
General Design Considerations
The cupboard footprint needs to be at least
650mmsquareforstandardunitsupto300litres,
730mmfor400litreand575mmforslimlineunits.
The base chosen for the cylinder should be level
andcapableofsupportingtheweightoftheunit
whenfullofwaterasshowninGeneralData. The
discharge pipework for the safety valves must
have a minimum fall of 1 :200 from the unit to a
safedischargepoint.Allexposedpipeworkshould
beinsulatedandtheunitshouldNOTbefixedina
locationwherethecontentscouldfreeze.
The pipe connecting the boiler flow to the
appliance must not be less than 22mm
copper or equivalent.
MainsWater Supply
Existing properties with a 15mm supply will be
satisfactory provided the local mains pressure is
good,but should be confined to single bathroom
properties.Fornewpropertieswheresimultaneous
demand is required to more than one bathroom
or a bathroom and one or more en-suites, the
communicationandservicepipe intothedwelling
should be a minimum of 22mm (usually in the
form of a 25mm MDPE supply). The optimum
performance is achieved if the inet pressure is
3 bar dynamic. However, the Solfex unvented
cylinder will function with lower inlet pressures,
but this will reduce the performance. There
should be a flow of at least 30 litres per minute or
above available into the property. Normally Solfex
UnventedCylinderprovideswellinexcessof40litres/
min in most conditions. Flow rates for ALL mains
pressuresystemsaresubjecttodistrictpressuresand
systemdynamicloss.Particularlyonlargerproperties
withmorethanonebathroom,thepipesizesshould
becalculatedinaccordancewithBS6700.
Model Selection
The suggested Direct model sizes, shown
opposite,are based on a typical days hot water
use assuming an Economy 7 tariff is provided.A
reductionofonemodelsizecannormallybemade
withanEconomy10 tariff.WhenusingtheDirect
models for high specification developments an
increaseofonemodelsizeshouldbeconsidered.
Where selecting a solar model, it is important to
checkthededicatedsolarvolume(shownintables1
&2)issuitableforthetotalfloorareaofthedwelling
toensurecompliancewithBuildingRegulations.The
maximum floor area of the dwelling permitted for
themodelsisshownopposite.
Thesuggestedmodelsizesarebasedontypicalhot
water usage.For high specification dwellings an
increaseofonemodelsize shouldbeconsidered.
I.V.
Combination Valve
I.V.
IftwoSolfexUnventedCylindersarecoupledtogetherthesecondaryinletandoutlet
pipes must be balanced.The units must be fitted on the same level.
Note:No valves must be fitted between the expansion vessel and the storage cylinder(s).
Standard and Slimline Model Selection Guide
Max hot water demand Max number of bed spaces
(Bedrooms)
Indirect
litres Direct litres
1 shower room Bedsit (0) 90 120
1 bathroom 2 (2) 120 150
1 bathroom 4 (3) 120 180
1 bathroom + separate shower room 6 (4) 150 210
1 bathroom + 2 separate shower rooms
or 2 bathrooms 7 (5) 180 210
2 bathrooms + separate shower room 7 (5) 210 250
2 bathrooms + 2 separate shower rooms 7 (5) 250 300
3 bathrooms + 2 separate showers rooms 9 (6) 300 400
3 bathrooms + 3 separate showers rooms 9 (6) 400 -
Solar Model Selection Guide
Max hot water demand Max floor
area (m2)Bedrooms Indirect
litres Direct litres
1 shower room 44 Bedsit - 180
1 bathroom 44 1-3 180 -
1 bathroom 66 1-3 210
1 bathroom + 1 shower room 66 1-3 210 -
1 bathroom + 1 shower room 84 1-3 - 250
1 bathroom + 2 shower rooms 84 2-4 250 -
1 bathroom + 2 shower rooms 113 2-4 - 300
2 bathrooms + 1 shower room 113 3-4 300 -
2 bathrooms + 1 shower room 150 4-5 - 400
2 bathrooms + 2 shower rooms 150 4-5 400 -

Page 13
INSTALLATION
INSTALLATION
General Restrictions
a. Thehighesthotorcoldwaterdrawoffpointshouldnotexceed10metresabovethe
PressureReducingValve.
b. AnascendingspraytypebidetoranyotherappliancewithaClass1back-syphonage
riskrequiringatype Aairgapshould notbeused.
c. Solfex Unvented Cylinder should not be used where steam is the primary heating
medium,orin a situationwheremaintenanceislikely to be neglected.
d. Unventedcylindersarenotsuitable forusewith solid fuelboilers.
e. Ifthesupply to the mixerfittings(otherthana dual outlet type) is nottaken
fromthebalancedsupplythesystemwillbecomeoverpressurizedandcause
the pressure relief valve to discharge. Over time this could also cause the
premature failure of the appliance itself which will not be covered by the
warranty,
f. In larger properties with a number of bathrooms/en-suites and long pipe runs
we would recommend that the balance cold supply is provided with its own
pressurereducingvalveandisnottakenfromthebalancedcoldconnectiononthe
combinationvalve. Inthiscaseitwillalsobenecessarytofitasmallexpansionvessel
onthebalancedcoldwatersystemtoaccommodatethepressurerisecausedbythe
increaseintemperatureofthebalancedcoldwater.
g. Check the performance requirements of the terminal fittings with regard to flow/
pressurearesuitable.
h. Inrelationtopotablewatersystems,expansionvesselsshallbeinstalledinavertical
orientationandlocatedsothatthelengthoftheconnectingpipeworkiskeptto
a minimum.
Shower Fittings
Aeratedtapsarerecommendedtopreventsplashing.Anytypeofshowermixingvalve
can be used as long as both the hot and cold supplies are mains fed. However, all
mainspressuresystemsaresubjecttodynamic changes particularly whenother hot
andcoldtaps/showersareopenedandclosed,whichwillcausechangesinthewater
temperature at mixed water outlets such as showers. For this reason and because
these are now no more expensive than a manual shower we strongly recommend
the use of thermostatic showers with this appliance. These must be used in 3 storey
properties where the impact on pressure/temperature of opening another tap in
the system is greater than normal.The shower
headprovided must also besuitable formains
pressure supplies.
Pipe Layout
Inallmainspressureinstallationsitisimportant
to remember that the incoming cold supply
mustbesharedbetweenallterminalfittings. It
isimportant thata 22mm supplyis broughtto
theapplianceanda22mmtake-offiscontinued
atleasttothebath. Iftherearetwobaths,28mm
pipeworkshould beconsidered. Onemetreof
smaller diameter pipework,or flow restrictors,
should be provided on the final connection to
all outlets so as to balance the water available.
In any event the distribution pipework should
generally be in accordance with EN806:1.
Plastic Pipework
This appliance is suitable for use with plastic
pipeworkaslongasthematerialisrecommended
forthepurposebythemanufacturerandisinstalled
fullyinaccordancewiththeirrecommendations.
Secondary Hot Water Circulation
Somemodelsarefittedwithasecondaryreturn
tappingasstandard(seetables1&2fordetails).
If fitted, an extra expansion vessel may be
necessary. Anon-returnvalveMUSTbeFITTED
nearthereturnconnection. Novalveorterminal
fitting should be installed between the non
return valve and the cylinder. (See schematic
arrangement on page 15.)
INCOMING COLD SUPPLY
M
DC
DC
DC
TO
EXTERNAL
TAP
SINK
WATER SOFTENER (IF NECESSARY)
WM or DWM
WHB W.C.
DC
DC
SH
DHW
WHB
WC BATH
SCV SCV
P&T
ERV/NRV
PRV
DCV
Note:
Cold supplies to single taps must be
taken from the mains cold water
system.
Cold supplies to mixer taps must be
taken from the balanced cold water
connection on the combination
valve.

Page 14
INSTALLATION
INSTALLATION
Typical Discharge Pipe Arrangement
15 mm
discharge
pipe
Expansion
relief
valve
Dotted line showing
alternative route with
single tundish being used
500 mm max.
P & T
Relief
Valve
300 mm
min.
22 mm metal pipe with continuous
fall up to 9m equivalent length (D2).
NOTES:
The discharge will consist of scalding
water and steam. Asphalt, roofing felt
and non-metallic rainwater goods may
be damaged by such discharges.
It is not acceptable to discharge straight
into a soil pipe.
Discharge below
fixed grating
Fixed
Grating
Trapped gully
Pressure & Temperature/expansion Relief
Valve Pipework
Thereliefvalveshouldbeinstalledtodischarge
in accordance with G3 of the Approved
Document of the Building Regulations and
should be piped to where it is visible, but will
not cause danger to persons or damage to
materials.
The following information is taken from
Approved Document G3 of the Building
Regulations and is provided to assist with
the design and installation of the discharge
pipework. However, the information is not
exhaustive and reference should always be
madetoApprovedDocumentG3oftheBuilding
Regulations.The final decision regarding any
arrangements rests with Building Control and
it is recommended that their advice is sought
if you have any concerns regarding this aspect
of the installation.
The two safety valves will only discharge
water under fault conditions. When operating
normally water will not be discharged.
The tundish should be vertical, located in the
samespace as the unventedhot water storage
system and be fitted as close as possible and
within 500mm of the safety device e.g. the
temperature relief valve.
Thedischargepipe(D2)fromthetundishshould
terminate in a safe place where there is no risk
to persons in the vicinity of the discharge,be
of metal and:
a) Be at least one pipe size larger than the
nominaloutletsizeofthesafetydeviceunless
its total equivalent hydraulic resistance
exceeds that of a straight pipe 9m long
i.e. discharge pipes between 9m and 18m
equivalent resistance length should be at
leasttwosizeslargerthanthenominaloutlet
size of the safety device, between 18 and
27mat least3 sizeslarger,andso on. Bends
must be taken into account in calculating
the flow resistance. Refer to the table and
the worked example.
An alternative approach for sizing
discharge pipes would be to follow BS6700
Specification for design installation,testing
andmaintenanceofservicessupplyingwater
for domestic use within buildings and their
curtilages.
b) Have a vertical section of pipe at least
300mm long,below the tundish before any
elbows or bends in the pipe work.
c) Be installed with a continuous fall.
WORKED EXAMPLE
TheexamplebelowisforG1/2temperaturereliefvalvewitha dischargepipe(D2)
having 4 elbows and length of 7m from the tundish to the point of discharge.
From the table below:
Maximumresistanceallowedforastraightlengthof22mmcopperdischargepipe
(D2)fromaG1/2temperaturereliefvalveis:9msubtracttheresistancefor4x22mm
elbows at 0.8m each = 3.2m.
Therefore the maximum permitted length equates to:5.8m.
5.8m is less than the actual length of 7m therefore calculate the next largest size.
Maximumresistanceallowedforastraightlengthof28mm pipe (D2)fromaG1/2
temperature relief valve equates to:14m.
As the actual length is 7m,a 28mm (D2) copper pipe will be satisfactory.
Sizing of copper discharge pipe‘D2’for a temperature relief valve
with a G1/2 outlet size (as supplied)
Size of discharge
pipework
Maximum length of
straight pipe
(no bends or elbows)
Deduct the figure below
from the maximum
length for each bend or
elbow in the discharge
pipe
22mm Up to 9m 0.8m
28mm Up to 18m 1m
35mm Up to 27m 1.4m

Page 15
INSTALLATION
INSTALLATION
d) Itispreferableforthedischargetobevisibleatboththetundishandthefinalpoint
of discharge but where this is not possible or practically difficult there should be
clearvisibilityatoneorotheroftheselocations. Examplesofacceptabledischarge
arrangements are:
1. Ideally below the fixed grating and above the water seal in a trapped gulley.
2. Downwarddischarges at a lowlevel;i.e.up to100mm aboveexternal surfaces
such as car parks,hard standings,grassed areas etc are acceptable providing
that where children play or otherwise come into contact with discharges, a
wirecage or similar guard ispositioned to prevent contact whilst maintaining
visibility.
3. Dischargesatahighlevel;e.g.intometalhopperandmetaldownpipewiththe
end of the discharge pipe clearly visible (tundish visible or not) or onto a roof
capable of withstanding high temperature discharges of water and 3m from
any plastic guttering systems that would collect such discharges.
4. Where a single pipe serves a number of discharges,such as in blocks of flats,
the number served should be limited to not more than 6 systems so that any
installationcanbetracedreasonablyeasily.Thesinglecommondischargepipe
shouldbeatleastonepipesizelargerthanthelargestindividualdischargepipe
to be connected.If unvented hot water storage systems are installed where
dischargesformsafetydevicesmaynotbeapparenti.e.indwellingsoccupiedby
blind,infirmordisabledpeople,considerationshouldbegiventotheinstallation
of an electronically operated device to warn when discharge takes place.
Safety
The safety devices supplied or fitted on an Solfex Unvented Cylinder are selected
for their suitability for the temperatures and pressures involved. They must not be
changed,removed or by-passed and it is essential that only genuine replacement
parts supplied or approved by Solfex Limited are used.This includes the immersion
heaters,whichmustincorporateanenergycut-out.Allpartsareavailabletoapproved
installers from Solfex Limited.
Combination Inlet Group
Combines elements 1,2 and 3 below.
1. PressureReducingValve -This must be fixed
near the cylinder. The cold water supply to
anymixertaps/showersmustbetakenfrom
thecoldwatertappingofthisvalvetoensure
balancedhotandcoldpressures. Thisvalve
isfactorysettoensurethecorrectoperating
pressure for the Solfex Unvented Cylinder.
2. Non Return Valve - This is integral with the
pressurereducingvalvetopreventbackflow
of hot water towards cold water draw off
points.
3. ColdWaterExpansionReliefValve-Thissafety
deviceispresetatthefactoryandwillrelieve
excesscoldwaterpressureresulting froma
fault condition.
P&T Relief Valve
Tundish
Hot Outlet
To Drain
PRV
ERV NRV
Stop
Tap
Kitchen
Cold
Tap Combination
Valve
Balanced
Cold
Outlets
Immersion Heater
Expansion
Vessel
Boiler
Return
Boiler
Flow
2 Port Valve
Secondary
Return Circuit
Schematic Diagram
Non Return
Valve
Pump

Page 16
INSTALLATION
INSTALLATION
Temperature/Pressure ReliefValve
This safety device is also pre-set at the factory and relieves before the temperature
reaches 100°C.It is also a Pressure ReliefValve,and is pre-set to 6 bar.
Immersion Heaters
These are 3kW 240V AC heaters and incorporate a thermostat and a manually reset
energycut-outwhichoperatesat80°C. Theyhaveincalloyelementstoprolongtheir
life expectancy in aggressive water conditions.
Please refer to tables 1 and 2 to clarify how many off peak and on peak immersions
are included with the unit you require.
Whereit is intendedthat unitsare fitted tooffpeakcircuits,then suitablecontrollers
such as the Horstmann off peak electric time controller will be required. External
wiringto the immersion heaters mustbe inaccordancewith therelevantIEEWiring
Regulations and the circuit must be protected by a suitable fuse and a double pole
isolating switch.
Thecorrectmethodofterminatingthewiringtotheimmersionheaterisshownabove.
Usage of the product in non-domestic commercial applications can be extremely
intensive and stressful to various components. We recommend that titanium
immersion heaters are fitted in such situations, rather than the incoloy heater
supplied as standard.Titanium immersion heaters offer superior strength, weight
and a smoother finish which enable them to better withstand the extreme stress
andtemperaturefluctuationoftenencounteredwithinnon-domesticenvironments
and situations where water quality is poor – ensuring improved performance and
extended operational life.
Line Strainer
This is integral within the combination inlet group to reduce the likelihood of
contaminantsfoulingthevalveseat. Followinginstallationthislinestrainermustbe
cleaned and replaced. This needs to be carried out on a regular basis.as part of the
annual maintenance/service check.
Tundish
Thisistoallowthedischargefrom anyReliefValvetobeseen. It must befittedaway
from any electrical devices. See page 14 for discharge pipework details.
Safety
Cut-out
Thermostat
Immersion HeaterWiring
E
L
N
Safety
The immersion heaters must be earthed and
they must be isolated from the mains before
the cover is removed on every occasion.
Replacement immersion heaters should be
obtained from Solfex Limited.
Control/Overheat DualThermostats
Care must be taken to ensure that the solar
probes are fully inserted into the pockets
provided.
AntiVacuumValve
Important - failure to follow the drain down
procedure will invalidate the waranty.(see
page 22)
NEVER drain the cylinder of hot water and
then close all cylinder inlets and
outlets.
REASON as the air remaining in the cylinder
cools the pressure inside the
cylinderwillfallbelowatmospheric
and cause the cylinder to implode.
NEVER close the cold main and drain the
cylinderviaanytapconnectedtoit.
REASON as the water drains, the pressure
inside the cylinder may decrease
below atmospheric and this will
cause the cylinder to implode.
To stop the possibility of this occurring by
accident an ANTI VACUUM VALVE should be
fitted in the hot water take off pipe.This will
balancethecylinder’sinternalandatmospheric
pressures and eliminate this risk.
Available from Gledhill part number GT056.

Page 17
INSTALLATION
INSTALLATION
Heating/primary Systems
Theboilerandprimary/heatingsystemsshould
be sized and installed in accordance with BS
5449.
Safety
Solfex Unvented Cylinder is fitted with a
CombinedTemperature/PressureReliefValveto
cope with any increase in system temperature
andpressureabovethedesignlimitations,when
usedwithboilersupto45kWoutput,whichisthe
maximumallowedbysectionG3oftheBuilding
Regulations. The primary water temperatures
shouldbe controlled as outlinedbelow.
Primary Circuit
Itisessentialthatthecircuitbetweentheboiler
and the Solfex Unvented Cylinder is pumped.
The motorised zone valve supplied should
be fitted adjacent to the unit and controlled
by the cylinder thermostat supplied. The
thermostatandmotorisedvalvemustbewired
sothattheybothswitchoffshouldanoverheat
situation develop. It is important to follow the
wiring diagram in the Wiring Section of these
instructions.
Sealed Primary Circuit
Any boiler used must be fitted with an over
temperaturecut-out.Unventedprimarycircuits
may be filled or replenished by means of a
temporaryconnectionbetweenthecircuitand
a supply pipe provided a‘Listed’double check
valve or some other no less effective backflow
prevention device is permanently connected
at the inlet to the circuit and the temporary
connection is removed after use.
Alternatively,aCAdevicecanbeused,whichwill
allowthesystemtobepermanentlyconnected
to the cold mains supply.The primary system
can then be topped up,when required,in the
samewayasanopenventedsystemfittedwith
an F&E Cistern.
GateValve
All our cylinders are tested to BS EN 12897 at
15 l/mim at which they exceed the minimum
requirements for heat up performance and
reheat in less time than the maximum reheat
times.
Inextremesituationswhereexcessiveflowrates,
above 25 l/min are present, then a gate valve
on the return from the cylinder to the boiler,
before it joins the central heating return,may
berequiredto reduceexcessiveflowratesand
therefore any potential noise problems.
Schematic OpenVented Primary System
Boiler
Pump
150mm max.
Warming/Overflow
Pipe
F & E Cistern
Minimum
distance as
required by
boiler
manufacturers
instructions
Motorised Valve
(Not supplied)
Motorised Valve
(Energy cut-out)
Gate Valve
(Not supplied)
Schematic Sealed Primary System
Boiler
Motorised Valve
(Energy cut-out)
Expansion
Vessel
Gauge
Safety Valve
Pump
Motorised Valve
(Not supplied)
Gate Valve
(Not supplied)

Page 18
INSTALLATION
INSTALLATION
Allcomponentsinasolarprimarysystemmust
be marked or identifiable in such a way that
their design pressure and temperature can be
readily determined.
Asafetydevice(pressurereliefvalve)tocontrol
theriskofover-pressureinsystemcomponents
should be fitted. A termination from a safety
pressure device should minimise the risk of
damage to persons or materials. Suitable
locationsare ahigh temperaturereceptacle,in
internalgullyorelseissueexternallyatground
level. High level termination from walls or on
roofs could cause injury to people or animals
below if the valve were to release scalding
water and steam.
The pipe leading to the safety device and the
collectorshouldbeofrigidandnon-deformable
construction, without any possibility of
restriction or disclosure by any other fitted
component.
Amoredetaileddiagramofourrecommended
arrangementforatypicalsolarsystemisshown
on page 20.
This provides all the necessary controls and
safetydevicesnecessaryforthesolarsystemi.e.
the two port zone valve is wired as an energy
cut out and the pump/valve will only allow
heat transfer as required under control of the
solar controller.
The solar pocket provided accommodates an
8mm diameter sensor which, with the sensor
located in the solar collector (or in the flow
pipe immediately adjacent to the collector),
will provide the information required by the
solar controller.
Note:Ifthemotorisedvalveisnotusedthen
any factory built hydraulic station for solar
useMUSTbefittedwithsuitablenon-return
valves in both flow and return pipes to
prevent gravity circulation when the pump
is not running.
Ifthereisapossibilityofthesolarcontrollerthat
youinstallcausingthecylindertemperatureto
exceed80°C,undernormalworkingconditions,
then a Solar tempering valve must be fitted to
the domestic hot water outlet of the cylinder.
This must limit the hot water temperature to a
maximumof60°C.(refbuildingregulationspart
G3 3.63).Suitable plumbing configurations for
installingthisvalveareshownonpage19ofthis
manual. NB. Any fitted Overheat thermostats
may require resetting in the winter months to
enablebackupheatsourcestoheatthecylinder.
Schematic Solar Direct System
Solar Pumping Station
Solar Panel
Expansion
Vessel
Solar
Controller
Motorised Valve
Energy cut-out
(Not supplied)
Schematic Solar Indirect System
Solar Pumping Station
Solar Panel
Expansion
Vessel
Solar
Controller
Motorised Valve
Energy cut-out
(Not supplied)
Motorised Valve
Energy cut-out
(Not supplied)

Page 19
INSTALLATION
INSTALLATION
Mixed HW out
Mains CW in
Figure 1:Cold port of the blending valve connected to mains supply
NOT ALLOWED
Mixed HW out
Mains CW in
Figure 3:Cold port of the blending valve connected to mains supply
to the vessel after the inlet control group
Mixed HW out
Mains CW in
Non-Return Valve (must be fitted)
Figure 2:Cold port of the blending valve connected to balanced cold
supply - NON-RETURNVALVE MUST BE FITTED
Fitting Blending Valves To The Unvented
Solfex Appliances
When fitting a blending valve to the unvented
appliances,it is important that the installation
does not contravene the G3,WRC and Health
and Safety directives or the manufacturers
recommendations. If this is the case, then
the warranty should be null & void. The key
requirementstocomplywiththeseregulations
are:-
1. Any fitting or material in contact with
potable water (e.g. a blending valve) must
beapprovedbyWRCoranequivalentbody.
2. Connections or wiring arrangements must
not bypass any safety devices.
3. Any expansion due to heating must not be
allowedtoexpandbackintothecoldmains.
4. The settings of any safety devices must not
be tampered with or adjusted.
The diagrams opposite shows how the
blending valve can be piped onsite.
Figure 1 shows the cold water port of the
blending valve connected to the mains cold
water supply before the inlet control group.
This arrangement is completely unacceptable
and illegal because:-
• the water is allowed to expand in to mains
cold water supply.
• the vessel will be charged to the incoming
mains supply which may be considerably
higher than the working pressure of the
vessel.
If this arrangement is used then the warranty
will not be valid.
Figure 2 shows the cold water port of the
blending valve connected to the balanced
cold water outlet.This arrangement will only
beacceptableif anapprovednon-returnvalve
is fitted,otherwise:-
• during the heating cycle, the water will
expand back into the mains supply, as the
regulating valve must not be relied upon
to act as a check valve under all operating
conditions.
• depending upon the characteristics of the
blendingvalve,hotwatermayalsoflowfrom
the balanced cold water taps.
Figure 3 shows the cold port of the blending
valveconnectedtothecoldwatersupplytothe
vesselaftertheinletcontrolgroup. Thisshould
be the preferred method. It is recommended
thattheinstallershouldensurethatthereisno
gravitycirculationinthepipeworkconnectedto
thecoldport.Ifnecessary,thiscanbeachieved
byfittinganon-returnvalveorusingathermal
trap.
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Page 20
INSTALLATION
INSTALLATION
1432
T
S1
S1
1 bar
Solar
Pumping
Station
Solar Coil
C12C1
+ C
o
+ C
o
L
Dual Thermostat
Solar Circuit
Solfex
Unvented Cylinder
TAnti Gravity
Check Valve
Pressure
Relief Valve
Anti Gravity
Check Valve
Standard 4 way
wiring junction box
(Not supplied)
No isolation valve
should be installed
between the solar
circuit and the safety
valve (pressure relief
valve)
Solar pump
supply from the
solar controller
Schematic Showing SolarWiring Requirements