VOKERA AquaFlow Release note

Supplied By www.heating spares.co Tel. [phone]
Installation
& Servicing
Instructions
THESE INSTRUCTIONS
TO BE RETAINED
BY USER
Vokèra is a licensed member of the Benchmark scheme
which aims to improve the standards of installation and
commissioning of domestic hot water systems in the UK.
AquaFlow Single coil water cylinder
AquaFlow Twin Twin coil water cylinder

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PLEASE LEAVE THIS MANUAL WITH THE UNIT AFTER INSTALLATION
00142046
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00
INSTALLATION MANUAL
This manual gives detailed advice for installation and should be read carefully
prior to fitting any unvented unit. This Vokera Aquaflow cylinder must be installed
by a competent person and be installed in compliance with the Vokera Aquaflow
Installation and Maintenance Instructions, all current legislation, codes of practice
and regulations governing the installation of unvented hot water cylinders in force
at the date of installation.
Components supplied with the unit for site fitting
(See also page 2/3 for component list)
*Multiblocvalve,includes pressure reducing valve, line strainer, balanced cold water take off, (for
shower or bidet only) check and expansion valve.Health and Safety
Manual Handling Operations Regulations 1992 defines manual
handling as: "any transporting or supporting of a load (including the
lifting, putting down, pushing, pulling, carrying or moving thereof) by
hand or bodily force" The Regulations set no specific requirements
such as weight limits. However common sense still has to be used
based on an ergonomic approach for each individual
DIMENSION AND WEIGHTS TABLE 1
PRODUCTREF. 150 200 250 210T250T
HEIGHT 900 1150 1600 1400 1600
DIAMETER 580 580 580 580 580
WEIGHT EMPTY 40 48 64 60 64
COIL RATING KW 12 26 26
UPPER COIL 12 12
LOWER COIL 12 26
* Tundish.
*1/2"F x 15 x 15 tee piece.
* Flexible hose.
* 3/4" x 22 mm Elbow / Drain Cock
*Commissioningvalve, 1/2" BSP male.
* Motorized valve.
* Expansion vessel
Components factory fitted
* Immersion heater(s).
* Thermostats / thermal cut-out.
* Temperature and pressure relief valve.
Installation details
The Vokera unvented unit is designed for use with supply pressure up to 16 bar. For pressures
over 16 bar an additional pressure reducing valve must be fitted in the supply pipe to the unit. Wall
mounting brackets are available for Vokera Aquaflow unvented units 120-200 litres capacity.
Aquaflow 150 - 200 - 250
AquaFlow Twin 210 - 250

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General Layout Fig: 1
KEY Part No KEY Part No
1 Flow ¾" BSPF 10 Flexible Hose 202108
2 Return ¾" BSPF 11 Secondary Return ½”BSPF
Fit ½"Fx½"Mx15mm Tee piece (Not
supplied)
3 Pressure Reducing Valve
Includes Item 4 510503 12 Commisioning Valve / Fitting (½" MI Drain Cock) 250440
4 Check and Expansion Valve 510505 13 Elbow / Drain Cock 250445
5 Temperature and Pressure
Relief Valve 550803 14 Cable Entry
6 Tundish 219002 15 Electrical Box
7 Immersion Heater 71255 16 Tee Piece 250006
7A Thermostat Immersion Heater
Thermostat Cylinder 80400 80511 17 Discharge Pipe (Not supplied)
8 Cold Feed Tube
(Not Supplied See Table 2) 18 Motorised Valve Not Factory Fitted)
92000
9 Hot Water Outlet 22mm
TABLE 2
Series Length of tube (ø22) mm
120 480 mm
150 585 mm
200 760 mm
INDIRECT
2
2
2
2
RESET
RESET
1
1
1
1
2
2
3
3
1
1
3
3
4
4
1
1
4
4
2
2
RESET
RESET
7
5
9
1
2
2
1
4
15
1
1
8
16
9
13
7a
8
6
17
10
5
4
3
1
1
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General Layout Fig: 1A
KEY Part No KEY Part No
1
1A Return ¾" BSP Return ¾" BSP 10 Flexible Hose 202108
2
2A Flow ¾" BSP Flow ¾" BSP 11 Secondary Return ½”BSPF Fit ½"Fx½"Mx15mm Tee piece (Not
supplied)
3 Pressure Reducing Valve
Includes Item 4 510503 12 Commissioning Valve / Fitting (½" MI Drain Cock) 250440
4 Check and Expansion Valve 510505 13 Elbow / Drain Cock 250445
5 Temperature and Pressure
Relief Valve 550803 14 Cable Entry
6 Tundish 219002 15 Electrical Box
7
7A Immersion Heater Immersion Heater Thermostat 71255 80020 16 Tee Piece 250006
7B
7C Thermostat Boiler Thermostat Solar 80030 80030 17 Discharge Pipe (Not supplied)
8 Cold Feed Tube
(Not Supplied See Table 2) 18 Motorised Valve Not Factory Fitted)
92000
9 Hot Water Outlet 22mm 19 Solar Sensor Bosses
20 Dip Pipe (removable)
20

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COLD WATER SUPPLY
1. To obtain the best performance from your Aquaflow unvented system it is advisable to feed
the unit with an uninterrupted supply.
2. Locate the water heater in a suitable position to facilitate the installation of the cold water
supply, discharge fittings and pipework. Also take into account access to the immersion
heaters and the commissioning valve.
3. Fit the combined male elbow / drain cock to cold supply point (13), so that the
compression fitting is vertical.
4. Fit the commissioning valve (12) to the commissioning fitting.
5. Fit both ½” male solar sensor pockets to the Solar Sensor bosses (19).
6. Fit the female outlet of the tee piece to the temperature and pressure relief valve (5) with the
horizontal connection facing right at approx. 45°.
7. Fit the tundish (6) to the tee piece using a short length of 15 mm copper tube.
8. Fit the length of copper tube 22mm specified in Table 2 to the cold feed elbow (see 3 above).
9. Fit the pressure reducing valve (3) to the top of the copper tube (see 7 above), so that the
black knob is facing right.
10. Connect the flexible hose to the 1/2" outlet of the expansion valve (4) and the horizontal outlet
of the tee piece (see 5 above). Discard compression nut & ring.
11. If a balanced mains pressure cold water supply is required to ashower or bidet (over rim
type only, ascending spray type requires type AA,AB or AD air gap), remove the blanking
cap from the pressure reducing valve (3) and connect to the shower or bidet cold supply.
(Major shower manufacturers advise fitting a mini expansion vessel in the balanced cold supply
pipework to accommodate thermal expansion and prevent tightening of shower controls) Using
the balanced cold connection to feed bath taps can reduce the flow available to the
unvented cylinder.
12. Before connecting the cold supply, flush the cold supply pipework of all flux and debris.
13. Connect the cold supply to the pressure reduction valve (Multibloc) (3).
Hot water supply
14. Connect the hot water supply pipe to the outlet (9). Ensure connection is water tight.
Secondary return
15. A secondary return facility is provided on all units. Fit a ½” F x ½” M x 15mm tee piece
between the commissioning valve (12) and the commissioning fitting. See also figure 4 on
page 16.
Discharge pipe
16. Connect the discharge pipe from the tundish (6.) This must have a continuous fall and be
fitted in accordance with The Building Regulations (see pages 5 and 12).

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Primary flow & return and motorised valve
17. The boiler primary flow and return connections should be made to the unit. The motorised valve
must be fitted into the primary flow. The primary flow and return fittings are 3/4" BSP female.
18. For electrical connection of the motorised valve and immersion heater, please read Electrical
Installation Instructions. (Pages 7 – 11)
Expansion Vessel
19. Connect the expansion vessel to the cylinder as shown in the diagram below. The
vessel should be charged/pressurised to the same pressure as the PRV (Pressure Reducing
Valve).
Solar Primaries
20. The Solar flow and return connections should be made to the lower coil connections.
Temperature control from the Solar circuit is achieved using a differential solar controller.
The solar pump must be wired in series through the thermal cut-out on the Aquaflow
cylinder (see figure3 page 12).
21. If the solar primary circuit contains a mechanical shut-off device, ensure that a non return
valve in the circuit prevents thermal siphoning if the circulation is stopped. Care should be
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taken to ensure the device is suitable for temperatures and fluids that may be present in a
solar-thermal system.
22. Temperature sensors for the cylinder provided with the differential controller should be
inserted into the pockets provided see figure 1A.
COMMISSIONING
Filling up
1. Open one hot water tap.
2. Close the commissioning valve (12).
3. Open the cold water supply valve.
4. When water flows from the open hot tap allow to flow to expel air from the system pipe work.
5. Open each hot water tap in turn to expel air from the system pipe work.
6. Check for leaks.
7Manually operate Temperature and Pressure Relief Valve (5) to ensure free water flow through
discharge pipe.(Turn knob to left.)
Draining
Switch off the electrical power off (Important to avoid damage to element). Isolate boiler from
Aquaflow unit. Turn off the cold water supply valve. Open hot water tap. Open drain (13). The unit
will drain.
SAFETY AND MAINTAINANCE
Safety Cut-out
1. The safety cut-out operates if:
a. Wiring is incorrect.
b. The immersion heater thermostat or cylinder thermostat fails.
c. Thermostat is set too high.
2. Remember before resetting the safety cut-out or altering the thermostat setting, isolate
electrical supply to the unit prior to removal of the electrical box lid.
3. Reduce thermostat setting and press the reset button. After adjustments are completed, ensure
the lid to the electrical box is replaced correctly and the retaining screw is fitted.
4. If still out of operation, contact installer.
Cold or tepid water discharge from tundish
1. Turn off the electrical supply to the immersion heaters.
2. Turn off cold water supply valve.
3. Open a hot tap.
4. Recharge the expansion vessel to the setting of the pressure reducing valve.
5. Close all hot taps.
6. Open mains supply valve

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7. Open and close a hot tap to ensure continuity of supply
8. Turn on electrical supply to the immersion heaters.
Hot water discharge from tundish
This indicates a malfunction of a thermal cut-out, operating thermostat or the combined temperature
and pressure relief valve. Turn off the electrical supply to the immersion heater and also isolate an
indirect unit from the boiler. Contact the installer or competent engineer.
INSTALLATION AND SERVICING INSTRUCTIONS
Cold water inlet control (Multibloc) See Page 2/3 Items 3 - 4
This combination consists of a pressure reducing valve with integral strainer, check valve and
expansion valve with stainless steel seat. The pressure settings are set and locked in the factory
and are shown on the top of each valve. For optimum performance the following installation
instructions should be complied with.
Installation
1. Cold water supply to be 22 mm nominal size.
2. Flush supply pipework before connection to remove all flux and debris prior to fitting the inlet
controls. Failure to do this may result in irreparable damage to the controls and will invalidate
the warranty.
3. The "MULTIBLOC" can be fitted in any orientation to suit the installation as long as it is fitted in
the correct flow direction. Check the flow arrows on the side of the body.
4. The expansion valve should be either horizontal or upright - if fitted inverted, debris may be
deposited on the seat and cause fouling of the seat when the valve operates. Check direction of
flow arrows.
5. The black plastic plugs in the body are pressure gauge connections to enable pressure
monitoring to be carried out, should the system develop a fault. It is recommended that these be
accessible (the pressure reducing valve has two - only one need be accessible).
6. Expansion relief drain pipework must be connected to a safe visible discharge point via a
tundish and the pipework must have a continuous fall.
7. The pressure reducing valve has two outlets, the second one is for a balanced cold water
supply, to a shower or a bidet (over rim type only, ascending spray type requires type
AA,AB or AD air gap) (Major shower manufacturers advise fitting a mini expansion vessel in
the balanced cold supply pipework to accomodate thermal expansion and prevent tightening of
shower controls) Using the balanced cold connection to feed bath taps can reduce the
flow available to the unvented cylinder. The balanced cold supply is blanked off.
NOTE: If the unit has been commissioned and is to be unused for more than 8 weeks it is
advisable to turn off the cold supply and draw off approximately 5 litre of water through a hot
tap. NB The cold supply must be opened prior to use.
The Benchmark Log Book enclosed with the cylinder should be completed after
commissioning the system and handed to the customer for future reference.

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MAINTENANCE
Under normal circumstances the "MULTIBLOC" combination control valve should not require any
maintenance. However, annual inspection and / or cleaning of the integral line strainer, pressure
reducing valve, cartridge, expansion relief valve cartridge and seating may be necessary depending
on local water conditions.
Pressure reducing valve
1. Isolate cold water supply.
2. Unscrew the retaining nut of the valve.
The complete operating mechanism,
including the strainer can be removed.
3. Clean the filter mesh and the cartridge
under running water.
4. Replace cartridge ensuring that strainer is
correctly located and reassemble the unit.
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Pressure Reducing Valve cartridge and
strainer Part No. 510 501 2.1 Bar.
Expansion relief cartridge
1. Isolate cold water supply.
2. Unscrew blue expansion relief headwork
from valve body.
3. Clean valve seat face and seating - do not
scratchordamageeithersealfaceorseating.
4. Refitin reverse order.Donot overtighten.
Expansion valve cartridge and seat Part No.
214009 8.0 Bar. Complete Expansion Valve
Part No. 510 505 8.0 Bar.
Tundish
Install the Tundish in a vertical position within a maximum of 500 mm from the Temperature and
Pressure Relief Valve drain connection. Ensure the expansion relief pipework discharges through
the tundish. Tundish pipework must be 22 mm with a minimum vertical length of 300 mm below
tundish. Maximum permitted length of 22 mm pipework is 9 m. Each bend or elbow is equivalent to
0.8 m of pipework. All pipework must have continuous fall and discharge in a safe, visible position. If
any doubt, refer to Building Regulation G3.
Spare Parts Expansion valve
(Cartridge)
Part No.
8.0 Bar 214009
6.0 Bar 214005
4.0 Bar 214046
Pressure reducing valve
Cartridge and strainer
Part No. 510 501
2.1Bar
Expansion valve
Part No. 510 505
8.0Bar

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ELECTRICAL INSTALLATION
Immersion heaters
All units are fitted with one immersion heater which is located behind the electrical box.
Indirect Units Upper Coil
Motorised valve
To comply with regulations governing the installation of indirect unvented cylinders, a motorised
valve must be fitted in the primary flow. Your Aquaflow unit has been supplied with a two port
motorised valve, which will act as a positive energy cut-out should the safety cut-out operate. The
motorised valve will also control the temperature of the domestic stored water via the cylinder
thermostat, which is located in the electrical box. The unit should be installed on an "S" or "Y" plan
system. Cylinder temperature control can also be achieved via the solar thermostat when the boiler
is not operational.
Please follow the instructions carefully. All electrical connections must conform to current IEE
wiring regulations. The working thermostat which controls the temperature of the domestic hot water
(see fig. 2/2A/2B/2C) is adjustable between 45°C - 75°C. A safety cut out is also incorporated
within the thermostat and will operate at 85°C ± 3°C. Should the safety cut out be brought into
operation, the motorised valve will operate and close down the primary flow to the cylinder. To reset
the safety cut-out and the motorised valve the reset button must be pressed in (see fig.
2/2A/2B/2C).If using a 6-wire 28mm or 1” BSP V4043H on either circuit the white wire is not needed
and must be made electrically safe.
Lower (Solar) coil
Heat sources to unvented hot water cylinders must be controlled by a thermal cut-out as well as a
thermostat. The Aquaflow Twin is supplied both with bosses for solar sensor pockets and the
pockets themselves. The top half of the thermostats fitted to the cylinder is a thermal cut-out. The
solar controller (not supplied) and solar sensor point should be wired through the Aquaflow Twin
Thermal cut-out.
Please note that the direction of flow in the solar coil is reversed compared to the boiler coil. If the
cylinder is not being used for solar use, connect the lower coil according to the instructions for the
upper coil.
Vokera can not be responsible if alternative wiring plans are used.
Important: Before resetting the safety cut-out or altering the thermostat setting isolate
electrical supply to the unit before removal of the lid.

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’S’ Plan systems
Refer to the wiring diagrams contained within the boiler installation instructions for the wiring of ’S’-
Plan systems. Connect the cylinder thermostat as shown in the diagram below
S Plan System Schematic
2A

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Y Plan Wiring Layout
Refer to the wiring diagrams contained within the boiler installation instructions for the wiring of ’Y’-
Plan systems. Connect the cylinder thermostat as shown in the diagram below.
NOTE
A10 way junction boxmustbeused ontheYplansystem.
B
Y Plan System Schematic
2C

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Solar Schematic
230V supply from solar
controller to Solar Pump
230V supply to Solar
Pump
Please note that the
power to the Solar Pump
from the solar controller
must pass through solar
thermostat
Solar Thermal cut of
f
AQUAFLOW FAULT FINDING GUIDE
FAULT POSSIBLE CAUSE REMEDY
No water flow from hot taps 1. Mains supply off.
2. Strainer blocked.
3. Cold water inlet Pressure
Reducing Valve incorrectly
fitted.
1. Check and open stopcock.
2. Turn off water supply. Remove
strainer and clean. (See Pressure
Reducing Valve page 6 Installation
Manual)
3. Check and refit as required.(see item
3 page 5 of installation manual)
Water from hot taps is cold. 1. Immersion heaters not
switched on.
2. Immersion heater thermal cut-
out has operated.
3. Programmer set to central
heating or not switched on.
4. Boiler not working.
5. Cylinder thermal cut-out has
operated.
6. Motorised valve not operating
correctly.
1. Check and switch on.
2. Check and reset button. (See
thermostat diagram page
9 and safety cut-out on page 4 of
Installation manual).
3. Check and set to hot water.
4. Check boiler operation. If fault
suspected consult installer or boiler
manufacturer.
5. As at No. 2.
6. Check wiring and / or plumbing
connections to motorized valve. (See
pages 8 or 10 of the installation
manual).

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Intermittent water discharge. 1. Reduced expansion capacity.
2. Thermal control failure.
(Note Water will be hot).
1. Recharge expansion vessel to correct
charge (same as pressure reducing
valve).
2. Switch off power to immersion
heater(s) and boiler supply to the unit.
When discharge has stopped, check
thermal controls, replace if faulty.
Contact a competent person.
Continuous water discharge. 1. Cold water inlet Pressure
Reducing Valve not
working.
2. Temperature and pressure
relief valve faulty.
3. Expansion relief valve not
working correctly.
1. Check pressure from valve if greater
than 2.1 bar replace. (See page 6 of
installation manual)
2. As No. 2 of above.
3. Check and replace if faulty. (See
page 6 of installation manual).
NOTE: Disconnect electrical supply before removing any electrical equipment covers.
AQUAFLOW FAULT FINDING GUIDE
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Notes:

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ALTERNATIVE DISCHARGE
Downwarddischargesatlowlevel,i.e.up to100mmaboveexternalsurfacessuch ascarparks,hardstandings,grassedareas
etc.areacceptableprovidingthatwherechildrenmayplayorotherwisecomeintocontactwithdischarges,awirecageorsimilar
guardispositionedtopreventcontact,whilstmaintainingvisibility.
Dischargeathighlevel,i.e.intoametalhopperandmetaldownpipe
with the end of the discharge pipe clearly visible (tundish visible or
not) or onto a roof capable of withstanding high temperature
dischargesofwaterand 3mfrom anyplastics guttering system
thatwouldcollectsuchdischarges(tundishvisible).
Where a single pipe serves a number of discharges, such as in
blocksofflats,the numberservedshouldbelimited to not morethan
6 systems so that any installation discharging can be traced
reasonablyeasily.Thesinglecommondischargepipeshouldbeat
leastonepipesizelargerthanthelargestindividualdischargepipeto
be connected. For furtherinformation contactyourBuilding Control
OfficeorTheBritishBoardofAgrément.
SECONDARYRETURN
AllreplacementpartsmustbesuppliedbyVokera.
To obtain the address of a local stockist contact:
FIGURE 3
FIGURE 4
1 Secondary Return use ½”Fx½”Mx15mm Tee (not supplied)
2Commisioning Valve
3Non Return Valve
4 Circulation Pump
5Secondary Return Line
6Balanced cold supply for showers or bidet only.
Vokera Ltd. www.vokera.co.uk.
Borderlake House
Unit 7 Riverside Ind Est
London Colney
AL2 1HG E-mail: [email protected]
Phone: [phone]
Fax: [phone] A Riello Group Company.
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Registered address:
Vokèra Ltd
Borderlake House
Unit 7 Riverside Industrial Estate
London Colney
Herts AL2 1HG
[email protected]
www.vokera.co.uk
www.vokera.ie
Sales, General Enquires
T0844 391 099
F0844 391 0998
Vokèra Ireland
West Court, Callan
Co Kilkenny
T056 7755057
F056 7755060
Vokèra Limited reserve the right to change
specification without prior notice
Consumers statutory rights are not affected.
A Riello Group Company.
Company Reg No: 1047779