Velux TFF 200 Manual

TFF 200/300/400 0201
VAS 451890 - 0207
Warning to the user
a. Do not remove or adjust any component part of this unvented water heater. Contact the installer.
b. If this unvented water heater develops a fault, such as a flow of hot water from the discharge pipe, switch the heater o
and contact the installer.
Warning to the installer
a. This installation is subject to Building Regulation approval. Notify the Local Authority of an intention to install.
b. Use only manufacturer’s recommended replacement parts.
c. Installed by:
Name:
Address:
Phone no.:
Completion date:
Directions for use

Figures and illustrations used. Due to the possibility of setting and printing errors, and to the need for continuous technical change, please
understand that we cannot accept liability for the correctness of the data. The current version of the General Terms of Business applies.

1 Safety instructions............................................................................................................................................................ 3
2 Installing the storage tank............................................................................................................................................... 4
3 Commissioning the storage tank.................................................................................................................................... 10
4 Anode and water quality.................................................................................................................................................................... 10
5 Electrical heating element................................................................................................................................................................ 11
6 Warranty conditions.............................................................................................................................................................................. 11
7 Service....................................................................................................................................................................................................... 11
8 Maintanence.............................................................................................................................................................................................. 13
9 Technical specifications....................................................................................................................................................................... 14
SECTION I: TANK INSTALLATION
3 VELUX
1. Safety instructions
Please read the following installation and commis-
sioning instructions thoroughly before you commis-
sion the device. This can prevent damage to your
system caused by incorrect handling.
Uses other than the intended use or unapproved
modifications to the installation and design nullify
all warranty claims.
The following regulations of technology must be re-
spected as well as directives of respective countries:
DIN 1988
Technical regulations for drinking water plumbing.
DIN 4753
Water heaters and water heating systems for
drinking and service water; Requirements, marking,
equipment and testing.
EN 12975
Thermical solar systems and their components.
1.1 Storing
When receiving the VELUX solar hot water unit and
before installation please store in an upright position
in a dry and weather secure storing facility.
Please read and understand these instructions before starting the work.
Please leave this leaflet with the user following installation.

4 VELUX
SECTION I: TANK INSTALLATIONSECTION I: TANK INSTALLATION
2. Installation
The tank must be assembled and installed by a certi-
fied specialist company!
When transporting and opening the packaging, the
instructions in the note attached to the head of the
buer must be followed. The dimensions of the tank
may not exceed the max. insertion dimensions!
The storage tank must be installed in a frost-proof
room with short cable routes. When installing the
unit in an attic, a suitable collecting basin with a
drain unit must be provided.
The weight of the filled tank may not exceed the
max. permitted ceiling loading! See the weight of
the tank when full under section 9.
The storage tanks, enameled in accordance with DIN
4753, part 1, are suitable for normal drinking water.
Mixed installation is permitted.
It must be connected in accordance with DIN 1988
and DIN 4753, part 1. All connection sockets not
used must be closed with plugs.
The operating overpressure ratings specified on the
type plate may not be exceeded. If necessary, a pres-
sure reducer must be installed.
The enclosed adjusting feet allow the storage
tank to be adapted for height dierences at its
installation location.
The unit has to be installed in such a way that main-
tenance can be carried out conveniently. Make sure
there is enough header above the tank to enable the
anode to be checked and possibly replaced.
Components check list:
Before commencing installation, check that all components for your VELUX solar hot water unit are contained
in the package. The following components are supplied as standard with your VELUX solar hot water unit:
• Cold water combination valve pack
Valve comprising pressure reducing valve, strainer, check valve and expansion relief valve.
Tundish
Expansion core unit
• Factory fitted Temperature/Pressure Relief Valve
• Factory fitted indirect Thermostat and Thermal Cut-out
• 2 Motorised valves
• Solar pack
Pump and control unit for easy mounting
Expansion vessel
Installation kit for expansion vessel
Mixer valve
Air separator
Glycol

5 VELUX
SECTION I: TANK INSTALLATIONSECTION I: TANK INSTALLATION
Please note! Cylinder relief valve connections should not be used for any other purpose and no valves should
be fitted between the expansion valve and the storage cylinder.
2.1 Connection diagram cold water in accordance with BS7206
Stop valve
Water main
Expansion
valve
Expansion
vessel
Temperature
relief valve Hot water
Solar flow
Solar return
Discharge
Pressure
reducing valve
Check valve
Thermal cut-out
Thermostat
Motorized valve
Heating flow
Heating return
Motorized valve

2.2 Tank connection points
ITEM DESCRIPTION INSTRUCTION
1 TPR valve Factory fitted
2 Motorised valve See paragraph 2.4
3 Thermal cutout Factory fitted
4 Motorised valve See paragraph 2.4
5 Solar pump and control See section l & ll
A
WW
HW
FH
Z
HR
FS
KW
EHP
F
See diagram in section 1, paragraph 2.8
For connection of the discharge pipe work.
Boiler circuit
Collectur circuit
See diagram in section l, paragraph 2.1
For connection of unvented kit components
to the cold water inlet.
SECTION I: TANK INSTALLATIONSECTION I: TANK INSTALLATION
1
3
5
4
6 VELUX
Boiler circuit
SV/SR
2

2.3 Discharge pipework
The discharge pipe (D1) from the vessel up to and
including the tundish is generally supplied by the
manufacturer of the hot water storage system.
Where otherwise, the installation should include the
dishcarge pipe(s) (D1) from the safety devise(s). In
either case the tundish should be vertical, located in
the same space as the unvented hot water storage
system and be fitted as close as possible and wihtin
500 mm of the safety device, e.g. the temperature
relief valve.
The discharge pipe (D2) from the tundish should
terminate in a safe place where there is no risk to per-
sons in the vicinity of the discharge, be of metal and:
a. be at least one pipe size larger than the nominal
outlet size of the safety device unless its total
equivalent hydraulic resistance exceeds that
of a straight pipe 9 m long, i.e. discharge pipes
between 9 m and 18 m equivalent resistance
length should be at least two sizes larger than the
miminal outlet size of the safety device, between
18 and 27 m at least three sizes larger, and so on.
Bends must be taken into account in caluclating
the flow reistance. Refer to the discharge pipe
arrangement, the copper discharge pipe table and
the worked example;
An alternative approach for sizing discharge pipes
would be to follow BS 6700:1987 Specification
for design, installation, testing and maintenance of
services supplying water for domestic use within
buildings and their curtilages, Appendix E, section
E2 and table 21.
b. have a vertical section of pipe at least 300 mm
long, below the tundish before any elbows or
bends in the pipework;
c. be installed with a continuous fall;
d. have discharges visible at both the tundish and the
final point of discharge but where this is not pos-
sible or is practically dicult there should be clear
visibility at one or other of these locations. Exam-
ples of acceptable discharge arrangements are:
i. ideally below a fixed grating and above the water
seal in a trapped gully;
ii. downward discharges at low level, i.e. up to 100
mm above external surfaces such as car parks,
hard standings, grassed areas, etc. are accpeta-
ble provided that where children may play or
otherwise come into contact with discharges a
wire cage or similar guard is positioned to prevent
contact, whilst maintaining visibility;
iii. discharges at high level, e.g. into a metal hop-
per and metal down pipe with the end of the
discharge pipe clearly visible (tundish visible or
not) or onto a roof capable of withstanding high
temperature discharges of water and 3 m from
any plastic guttering system that would collect
such discharges (tundish visible);
iv. where a single pipe serves a number of discharg-
es, such as in blocks of flats, the number served
should be limited to no more than 6 systems so
that any installation discharging can be traced
reasonably easily. The single common discharge
pipe should be at least one pipe size larger than
the largest individual discharge pipe (D2) to be
connected. If unvented hot water storage systems
are installed where discharges from safety
devices may not be apparent, i.e. in the dwell-
ings occupied by blind, infirm or disabled people,
consideration should be given to the installation
of an electronically operated device to warn when
discharge takes place.
NOTE: the discharge will consist of scalding water
and steam. Asphalt, roofing felt and non-metal-
lic rainwater goods may be damaged by such
discharges.
SECTION I: TANK INSTALLATIONSECTION I: TANK INSTALLATION
7 VELUX

Typical discharge pipe arrangement
Safety device
(eg. temperature relief value).
500 mm maximum
300 mm minimum
Metal discharge pipe (D1) from temperature relief
valve to tundish.
Tundish
Metal discharge pipe (D2) from tundish, with
continuous fall.
See Building Regulation G3 section 3.9d i-iv,
Tabel 4 and worked example.
Discharge below fixed grating
(Building Regulation G3 section
3.9d gives alternative points of
discharge).
Fixed louvred grating
Trapped gully
2.3.1 Sizing of copper discharge pipe ’D2’ for common temperature relief valve outlet sizes
Valve
outlet size
Minimum size of
discharge pipe D1*
Minimum size of
discharge pipe
D2* from tundish
Maximum resistance allowed,
expressed as a length of straight
pipe (ei. no elbows or bends)
Resistance created by
each elbow or bend
G½ 15 mm
22 mm
28 mm
35 mm
up to 9 m
up to 18 m
up to 27 m
0.8 m
1.0 m
1.4 m
G¾ 22 mm
28 mm
35 mm
42 mm
up to 9 m
up to 18 m
up to 27 m
1.0 m
1.4 m
1.7 m
G1 28 mm
35 mm
42 mm
54 mm
up to 9 m
up to 18 m
up to 27 m
1.4 m
1.7 m
2.3 m
SECTION I: TANK INSTALLATIONSECTION I: TANK INSTALLATION
8 VELUX

Worked example
The example below is for a G½ temperature relief
valve with a discharge pipe (D2) having 4 No.
elbows and length of 7 m from the tundish to the
point of discharge.
From Tabel 2.3.1
Maximum resistance allowed for a strength length
of 22 mm copper discharge pipe (D2) from a G½
temperature relief valve equates to 9 m.
Substract the resistance for 4 No. 22 mm elbows at
0.8 m each = 3.2 m. Therefore the maximum permit-
ted length equates to 5.8 m.
5.8 m is less than the actual length of 7 m therefore
calculate the next largest size.
Maximum resistance allowed for a straight length of
28 mm pipe (D2) from a G½ temperature relief valve
equates to 18 m.
Substract the resistance for 4 No. 28 mm elbows at
1 m each = 4 m. Therefore the maximum permitted
length equates to 14 m.
As the actual length is 7 m, a 28 mm (D2) copper
pipe will be satisfactory.
2.4 Motorised valves
See instruction supplied with the valve.
NB: High limit stat to be set at 80-85°C.
High limit stat is set at 80-85°C.
Control stat is set at 70-75°C.
2.5 Dual thermostat
2.5.1 Connection diagram
SECTION I: TANK INSTALLATIONSECTION I: TANK INSTALLATION
c2 1
°c +
c2
°c +
9 VELUX
c2 1
°c +
c2
°c +
Control Limit

10 VELUX
3. Commissioning
Before commissioning, check whether the water
supply is open and the storage tank is full. Initial
filling and commissioning must be carried out by a
certified specialist company!
The entire system, including parts assembled in the
manufacturer’s factory, must be tested to ensure
that it is watertight and operational. The safety
valve must be checked regularly to ensure that it
functions safely.
We recommend that you have the system serviced
annually by a specialized company.
We recommend that the storage tank be cleaned
and checked annually.
Careful operation can save a considerable amount of
energy. Do not run the storage tank at more than
60°C, as this results in heat loss and limescale.
The ideal temperatures are 50-60°C.
4. Anode and water quality
In accordance with DIN 4753, the magnesium anode
must be tested by the customer service department
after 2 years for the first time (after that annually)
and replaced if necessary.
In hard water areas scaling can be reduced by
restricting the water temperature. For descaling see
section 8.
SECTION I: TANK INSTALLATIONSECTION I: TANK INSTALLATION
2.5.2 Specification
ITD Dual Thermostat
Temperature Range (Control) (°C) 0-90
Temperature Range (Limit) 90/110°C (factory set to 90°C)
Switching Dierential 4 ± 1K
Switch Configuration PDT (control) SPST (limit)
Switch Voltage Rating 220/240 Vac
Switch Current Rating 10(2.5)A
Maximum Ambient Temperature (Head) 80°C
Maximum Medium Temperature 150°C
Dimensions of thermostat head (mm) 100 wide x 110 high + 56.5 deep

11 VELUX
5. Electrical heating element
Electrical heating elements may only be connected
by certified electrical installers in accordance with
the corresponding switching diagram. The country-
specific regulations in eect must be observed.
The electrical heater (if applicable) must be descaled
annually and also at regular intervals depending on
the hardness of the water. A function control must
be connected.
The electric threaded heating elements are only
permitted to be used as backup heating.
Only electrical heating elements with thermostat
and thermal cut-out from VELUX should be used for
this product.
Note: Electrical heating elements must never be
fitted without thermal cut-outs.
6. Warranty conditions
The vendor guarantees the storage tank enameling
and rust-proofness for 5 years from the date of
manufacturing, provided the protective magnesium
anode has been tested regularly.
All spare parts are guaranteed for 2 years.
i. Servicing should only be carried out by a compen-
tent installer in the installation and maintenance of
unvented solar water heating systems.
ii. Any spare parts used MUST be authorised VELUX
parts.
iii. Disconnect the electrical supply before removing
any electrical equipment covers.
7. Service
7.1 Important
SECTION I: TANK INSTALLATIONSECTION I: TANK INSTALLATION
iv. NEVER bypass any thermal controls or operate
system without the necessary safety valves.
v. Water contained in the VELUX solar hot water
system may be very hot, especially following a
thermal control failure. Caution must be taken
when drawing water from the unit.

7.2 Spare parts
A full range of spare parts are available for the VELUX solar hot water system range. Refer to the Technical
Data label on the unit to identify the model installed and ensure the correct part is ordered.
SECTION I: TANK INSTALLATIONSECTION I: TANK INSTALLATION
ITEM DESCRIPTION ITEM NAME ITEM NO. TFF 200 0201 TFF 300 0201 TFF 400 0201
Storage tank covers
Cap, silver (D = 540 mm) ELB200AH-S 121736 •
Cap, silver (D = 600 mm) ELB3AH-S 121737 •
Cap, silver (D = 704 mm) ELB4/5AH-S 120069 •
Flange covers
Flange cover DN 110, silver FPADN110S 120041 • • •
Flange
Dummy flange DN 110 FP18000 120029 • • •
Flange lid, perforated for RWT, DN 110 FP18015 120028 • • •
Seals
Seal for flange lid, DN 110 FPD180 120038 • • •
Seal for flange lid, perforated FPD180G 120039 • • •
Mg anodes
Ø 26 x 550 anode, not insulated MGA-ELB 200R2E 120046 •
Ø 26 x 900 anode, not insulated MGA-SKL400 120047 •
Ø 26 x 1100 anode, not insulated MGA-SKL300/500 120043 •
Thermometers
Thermometer TFF 200 0201 BTM120R 120055 •
Foil cases
Foil case TFF 200 0201, silver ELB200R2E-FM 120049 •
Foil case TFF 300 0201, silver SKL300-FM-S 120050 •
Foil case TFF 400 0201, silver SKL400-FM-S 120051 •
Thermometers
Pressure reducing valve COLK 350 250 •
Pressure reducing valve COLK 350 300 • •
Expansion vessel XVES 600 023 •
Expansion vessel XVES 600 027 •
Expansion vessel XVES 600 031 •
Expansion vessel XVES 600 041
TPR PTEM 575 804 • • •
Tundish TUND 219 001 • • •
Double thermostat • • •
Motorised valves TBC • • •
12 VELUX

13 VELUX
SECTION I: TANK INSTALLATIONSECTION I: TANK INSTALLATION
8. Maintainance
8.1 Requirements
To ensure the continued optimum performance of the
VELUX Solar Hot Water unit it should be regularly
maintained. This is of particular importance in hard
water areas or where the water supply contains
particulate matter. Maintenance should be carried out
by a competent person and any replacement parts
used should be authorised VELUX spare parts. It is
8.2 Check Operation of Safety Valves
Slowly open the Temperature and Pressure Relief
Valve by twisting its cap for a few seconds. Check
water is discharged and that it flows freely through
the tundish and discharge pipe work. Check valve
reseats correctly when released.
8.3 Draining the VELUX Unit
Switch o the electrical supply to the immer-
sion heater(s) and shut down the boiler on
indirect units. Turn o the mains water supply to
the VELUX unit. Attach a hosepipe to the drain cock
having sucient length to take water to a suitable
discharge point below the level of the unit, at least
8.4 Descaling Immersion Heather
Open the cover(s) to the immersion heater housing(s)
and disconnect wiring from immersion heater(s).
Remove the thermostat and unscrew the immersion
heater. Carefully remove any scale from the surface
of the element(s). DO NOT use a sharp implement as
recommended that maintenance is carried out every
12 months and includes the checks detailed below.
In hard water areas consideration should be given to
periodically descaling the immersion heater elements
if fitted. To do this the VELUX unit will need to be
drained.
Note: The water discharged may be very hot.
Repeat the procedure for the Expansion Relief Valve
(located on the Cold Water Combination Valve or
Expansion Valve Core Unit).
one metre below the unit is recommended. Open hot
water tap nearest to the VELUX unit to relieve the
system pressure. Open drain cock. If water fails to
drain from the VELUX Unit vent the unit by manu-
ally opening the Temperature/Pressure Relief Valve.
damage to the element surface could be caused. En-
sure sealing surfaces are clean and seals are undam-
aged; if in doubt fit a new gasket. Replace immersion
heater. Rewire the immersion heater(s) in accordance
with instructions and close and secure terminal cover.

14 VELUX
SECTION I: TANK INSTALLATIONSECTION I: TANK INSTALLATION
8.6 Log Book
On completion of any maintenance or service of the
VELUX Solar Hot Water Unit fill-in a record of actions
taken and the date the work was undertaken. The
record should be kept with the instruction for use.
8.5 Refilling System
DO NOT switch on the immersion heater(s) or boiler
until the system has been completely refilled. Close
the drain tap. With hot tap open, turn on mains
water supply. When water flows from the hot tap
allow to flow for a short while to purge air and to
flush through any disturbed particles. Close hot
tap and then open successive hot taps in system
to purge any air. The electrical supply can now be
switched on.
TFF 200
0201
TFF 300
0201
TFF 400
0201
Contents l 180 280 375
Diameter, insulated mm 540 600 700
Height, insulated mm 1432 1794 1591
Tilted height mm 1530 1930 1745
Weight kg 85 120 140
Max. permissible water
pressure bar 5.5 5.5 5.5
Max. permissible heating
pressure bar 5.5 5.5 5.5
Max. permissible solar loop
pressure bar 5.5 5.5 5.5
Max. permissible operating temp.
water °C 95 95 95
Max. permissible operating temp.
heating °C 110 110 110
Max. permissible operating
temp. solar loop °C 110 110 110
Upper heating/reheating register m20.7 0.81 1.00
Lower heating area/solar
register m20.95 1.49 1.83
Solar heat exchanger vol. l 6.4 10.4 12.8
Heating system heat exchanger
vol. l 4.8 5.6 6.9
Performance indicator NLtop NL / kW 2.4 / 25 2.5 / 27 5.7 / 31
9. Specifications

15 VELUX
SECTION I: TANK INSTALLATIONSECTION I: TANK INSTALLATION
TFF 200
0201
TFF 300
0201
TFF 400
0201
Performance indicator NL
bottom NL / kW 4.2 / 31 4.1 / 45 9.4 / 51
Heating flow, HV R 1" 1" 1"
mm 1147 1424 1355
Heating return, HR R 1" 1" 1"
mm 787 1064 1007
Solar flow, SV R 1" 1" 1"
mm 687 965 909
Solar return, SR R 1" 1" 1"
mm 687 965 909
Hot water, WW R ¾" 1" 1"
mm 1369 1728 1526
Cold water, KW R ¾" 1" 1"
mm 55 90 55
Circulation, Z R ½" ½" ½"
mm 900 1179 1112
Sensor thermometer wells mm ø 16 x 200 ø 16 x 200 ø 16 x 200
Heating FH mm 1012 1289 1224
Solar FS mm 292 378 324
1½" sleeve for electrical
heating EHP mm 737 1015 957
Thermometer T mm 1226
Flange F, Di/TK/Do mm 110/150/180 110/150/180 110/150/180
Anode A mm ø 26 x 550 ø 26 x 1100 ø 26 x 900
mm Top Top Top
Maximum water supply pres-
sure to the pressure reducing
valve
bar 16 16 16
Operating pressure bar 3 3 3
Expansion vessel charge
pressure bar 3 3 3
Expansion relief valve setting bar 6 6 6
Mass of unit when full kg 285 420 540
Set opening pressure (bar) of
the combined temperature and
pressure relief valve(s)
bar 7 7 7
The set opening temperature
(°C) of the temperature relief
or temperature and pressure
relief valve(s)
°C 90 90 90
Specifications (continuation)
SV/SR
A
WW
HW
FH
Z
HR
FS
KW
EHP
F

SECTION II: SOLAR PUMP STATION
17 VELUX
1. Safety instructions
1 Safety instructions........................................................................................................................................................... 17
2 Dimensions, Components............................................................................................................................................... 18
3 Technical Specifications.................................................................................................................................................. 19
4 Function of the Gravity Brakes..................................................................................................................................... 19
5 Fill/Drain Fitting..................................................................................................................................................................................... 20
6 Flow Indicator.......................................................................................................................................................................................... 20
7 Air Jet............................................................................................................................................................................................... 20
8 Connection Nozzle................................................................................................................................................................................ 21
9 Connecting the Valve Coupling for Membrane Expansion Vessels........................................................................... 21
10 Solar Control/Electric Installation............................................................................................................................... 21
11 Maintenance.............................................................................................................................................................................................. 21
12 List of Spare Parts................................................................................................................................................................................. 22
13 Pump description................................................................................................................................................................................... 23
14 Safety precautions for the operator............................................................................................................................................. 24
Carefully read the following instructions for installa-
tion and use before you start operating your device.
In this way, you can avoid damages to your device
due to incorrect handling. Improper use and unau-
thorised modifications of the installation and design
result in the expiration of all liability claims. The fol-
lowing regulations of technology must be respected
as well as directives of respective countries:
DIN 4751
Water Heating Systems.
DIN 4757
Solar Heating and Solar Thermal Systems.
EN 18380
Heating and Process Water Systems.
EN 18382
Electric Cable and Wiring Equipment in Buildings.
EN 12975
Thermical solar systems and their components.

18 VELUX
SECTION II: SOLAR PUMP STATIONSECTION II: SOLAR PUMP STATION
2. Dimensions, components
Two-line return unit, insulated, DN 20, with solar control, air collector, fill fitting, and flow indicator.
Figure 1: Overview
14
Tube connection
Ø 22
Connection,
flat sealing G 1"
22
15
13
7
10
6
5
12
2
3
11
4
10
1
12
9
8
77.5 175 75.5
335 ca. 202.6
622
ca. 648.5
Figure 2: Dimensions

19 VELUX
SECTION II: SOLAR PUMP STATIONSECTION II: SOLAR PUMP STATION
Maximum operating pressure: 6 bar
Maximum operating temperature (return):
120°C
Maximum operating temperature (flow): 140°C
Medium:
Water with a maximum propylene glycol content of 50%
Nominal diameter: DN 20
Connections: Flat sealing, swivel nut G1, 1¼"
Sealings:
EPDM
Casing:
GK-CuZn37Pb (2.0340.02)
Fittings: CuZn39Pb3 (2.0401)
Insulation: EPP foam
Thermal conductivity: 0.038 W/mK
3. Technical Specifications
4. Function of the Gravity Brakes (1/2)
Opening pressure of the gravity brakes: 20 mbar
each.
The gravity brakes are integrated in the flow and
return ball valves. They are operated by turning the
handles of the ball valves.
To prevent gravity circulation, the valve discs should
not be vented. The gravity brakes are in operating
position (closed). The slots in the handles are in a
vertical position (Figure 3a).
To fill and completely empty the solar system, open
the gravity brakes by turning the handles to the
right. The slots in the handles are positioned at an
angle of 45° (Figure 3b).
Turn the handles to the right by a total of 90°.
The slots in the handles are in a horizontal position.
The ball valves are closed (Figure 3c).
Figure 3a: Ball Valve open. Figure 3b: Gravity Brakes open. Figure 3c: Ball Valve closed.

20 VELUX
SECTION II: SOLAR PUMP STATIONSECTION II: SOLAR PUMP STATION
5. Fill/Drain Fitting (6)
Use the fill and drain valves on the fill/drain fitting
to fill and drain the solar system (Figure 4).
To drain the system, the slot in the spindle must be
in a horizontal position (Figure 4b). Figure 4a: Drain Fitting
completely open.
Figure 4b: Drain Fitting
closed.
6. Flow Indicator (7)
The adjustment of the flow rate of the thermal
carrier medium takes place by controlling the speed
levels (I, II, III) of the circulation pump and the throt-
tle in the fill/drain fitting (Figure 4).
The flow indicator shows the set flow rate (Figure 5).
The indicator range is between 1 and 13 l/min.
7. Air Jet (8)
The residual air in the thermal carrier medium is
collected in the air jet and can be vented manually
by means of the venting nipple (Figure 1, pos. 9). To
do this, attach the enclosed hose to the nozzle of the
venting nipple and collect the escaping medium in a
suitable vessel.
Remove the hose after venting. Venting should
only be performed by trained professionals.
Uncontrolled venting can lead to malfunction of
the solar system due to loss of pressure.
CAUTION! Risk of scalding!
The air and the thermal carrier medium escaping
while venting the system can reach tempera-
tures of over 100°C.
Afterwards, firmly close the nipple. Monitor the
system pressure while venting. If necessary, refill the
solar system with thermal carrier medium.
Read volume flow
values at this edge
of the rotameter.
Figure 5: Flow Indicator.
13
11
9
7
5
3
1
4
Connection RP ¾"
female thread.
11
MEV connection,
flat sealing G¾"
male thread.
Figure 6: Membrane Expansion
Vessel Connection.