Viessmann VITODENS User manual

Operating instructions
for the system user
VIESMANN
Heating system with Vitotronic 100 control unit, type HC1B
For constant temperature mode
VITODENS
VITOPEND
5592 683 GB 8/2013 Please keep safe.

2
Please follow these safety instructions closely to
prevent accidents and material losses.
Safety instructions explained
Danger
This symbol warns against the risk of injury.
!Please note
This symbol warns against the risk of material
losses and environmental pollution.
Note
Details identified by the word "Note" contain additional
information.
Target group
These operating instructions are designed for heating
system users.
This appliance can also be operated by children of 8
years and older, as well as by individuals with reduced
physical, sensory or mental faculties or those lacking
in experience and knowledge, provided such individu-
als are being supervised or have been instructed in the
safe use of this appliance as well as in any risks aris-
ing from it.
!Please note
Supervise children in the proximity of the appli-
ance.
■Never permit children to play with the appli-
ance.
■Cleaning and maintenance must not be car-
ried out by unsupervised children.
Danger
Incorrectly executed work on the heating system
can lead to life threatening accidents.
■Work on gas installations must only be carried
out by a registered gas fitter.
■Work on electrical equipment must only be
carried out by a qualified electrician.
Danger
The appliance generates heat. Hot surfaces can
cause burns.
■Never open the appliance.
■Never touch the hot surfaces of uninsulated
pipes, fittings or flue pipes.
If you smell gas
Danger
Escaping gas can lead to explosions which may
result in serious injury.
■Do not smoke. Prevent naked flames and
sparks. Do not switch lights or electrical appli-
ances on or off.
■Close the gas shut-off valve.
■Open windows and doors.
■Evacuate any people from the danger zone.
■Notify your gas or electricity supplier and your
local heating contractor from outside the build-
ing.
■Shut off the electricity supply to the building
from a safe place (outside the building).
If you smell flue gas
Danger
Flue gas can lead to life threatening poisoning.
■Shut down the heating system.
■Ventilate the installation site.
■Close all doors in the living space.
In case of fire
Danger
If there is a fire, there is a risk of burns and
explosion.
■Shut down the heating system.
■Close shut-off valves in the fuel supply lines.
■Use a tested fire extinguisher, class ABC.
What to do if the heating system develops faults
Danger
Fault messages indicate faults in the heating
system. If faults are not rectified, they can have
life threatening consequences.
Do not acknowledge fault messages several
times in quick succession. Inform your heating
contractor so the cause can be analysed and
the fault rectified.
Installation room conditions
Danger
Sealed vents result in a lack of combustion air.
This leads to incomplete combustion and the
formation of life threatening carbon monoxide.
Never cover or close existing vents.
Do not make any subsequent modifications to
the building characteristics that could affect safe
operation (e.g. cable/pipework routing, cladding
or partitions).
Safety instructions
For your safety
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Danger
Easily flammable liquids and materials (e.g.
naphtha, solvents, cleaning agents, paints or
paper) can cause deflagration and fire.
Never store or use such materials in the installa-
tion room or in direct proximity to the heating
system.
!Please note
Incorrect ambient conditions can lead to heating
system damage and can put safe operation at
risk.
■Ensure ambient temperatures are above 0 °C
and below 35 °C.
■Prevent air contamination by halogenated
hydrocarbons (e.g. as contained in paints, sol-
vents or cleaning fluids) and excessive dust
(e.g. through grinding/polishing work).
■Avoid continuously high humidity levels (e.g.
through continuous drying of washing).
Extractors
Operating appliances that extract air to the outside
(cooker hoods, extractors, air conditioning units, etc.)
can create negative pressure. If the boiler is operated
at the same time, this can lead to reverse flow of the
flue gas.
Danger
The simultaneous operation of the boiler and
appliances that extract air to the outside can
result in life threatening poisoning due to
reverse flow of the flue gas.
Take suitable steps to ensure an adequate sup-
ply of combustion air. If necessary, contact your
heating contractor.
Auxiliary components, spare and wearing parts
!Please note
Components not tested with the heating system
may damage it or affect its functions.
Only have installation or replacement work car-
ried out by qualified contractors.
Safety instructions
For your safety (cont.)
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1. Introductory information Intended use .......................................................................................... 5
Commissioning ...................................................................................... 5
Your system is preset at the factory ....................................................... 5
Terminology ........................................................................................... 5
Tips on saving energy ............................................................................ 6
2. About the controls Controls ................................................................................................. 7
How to use the controls ......................................................................... 7
Symbols ................................................................................................. 7
3. Start-up/shutdown Starting the heating system ................................................................... 9
Shutting down the heating system ......................................................... 9
■With frost protection monitoring .......................................................... 9
■Without frost protection monitoring (shutdown) .................................. 10
4. Central heating Required settings for central heating ..................................................... 11
Setting the heating flow temperature ..................................................... 11
Setting the operating program (central heating) .................................... 11
Stopping the central heating .................................................................. 11
5. DHW heating Required settings (DHW heating) .......................................................... 12
Setting the DHW temperature ................................................................ 12
Setting the operating program (DHW heating) ...................................... 12
Stopping DHW heating .......................................................................... 12
Comfort function (if available) ................................................................ 13
6. Further adjustments Setting the temperature unit (°C/°F) ...................................................... 14
Restoring factory settings ...................................................................... 14
7. Calling up Calling up information and resetting values ........................................... 15
Calling up a service message ................................................................ 16
Calling up fault messages ...................................................................... 16
8. Multi boiler systems Special considerations for multi boiler systems ..................................... 18
9. Emissions test mode Activating emissions test mode ............................................................. 19
■Activating emissions test mode .......................................................... 19
■Stopping emissions test mode ............................................................ 19
10. What to do if... Rooms are too cold ................................................................................ 20
Rooms are too hot ................................................................................. 20
There is no hot water ............................................................................. 20
The DHW is too hot ............................................................................... 21
"ã" flashes on the display ..................................................................... 21
"E" flashes on the display ..................................................................... 21
"ë" flashes on the display ..................................................................... 21
"- - EP - -" flashes on the display ........................................................... 21
11. Repair work .................................................................................................................. 22
12. Keyword index .................................................................................................................. 24
Index
Index
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The appliance is only intended to be installed and
operated in sealed unvented heating systems that
comply with EN 12828, with due attention paid to the
associated installation, service and operating instruc-
tions. It is only designed for the heating of water that is
of potable water quality.
Intended usage presupposes that a fixed installation in
conjunction with permissible, system-specific compo-
nents has been carried out.
Commercial or industrial usage for a purpose other
than heating the building or DHW does not comply with
regulations.
Any usage beyond this must be approved by the man-
ufacturer for the individual case.
Incorrect usage or operation of the appliance (e.g. the
appliance being opened by the system user) is prohibi-
ted and results in an exclusion of liability. Incorrect
usage also occurs if the components in the heating
system are modified from their intended function (e.g.
if the flue gas and ventilation air paths are sealed).
Commissioning
The commissioning and matching of the control unit to
local conditions and building characteristics, as well as
instructing the user in the operation of the system,
must be carried out by your heating contractor.
As the user of new combustion equipment, you may be
obliged to notify your local flue gas inspector of the
installation [check local regulations]. Your local flue gas
inspector will also inform you [where appropriate]
about work he may be required to carry out on your
combustion equipment (e.g. regular checks, cleaning).
Your system is preset at the factory
The control unit is preset at the factory to " " for
central heating and DHW heating.
Your heating system is therefore ready for operation:
Central heating
■The rooms are heated in accordance with the set-
tings on your control unit and room temperature con-
trol unit.
■Your heating contractor can make further settings for
you during commissioning.
You can change any settings individually at any time
to suit your requirements (see chapter "Central heat-
ing").
DHW heating
■The DHW is heated up to 50 °C.
■Your heating contractor can make further settings for
you during commissioning.
You can change any settings individually at any time
to suit your requirements (see chapter "DHW heat-
ing").
Frost protection
■Your boiler and DHW cylinder are protected against
frost.
Power failure
■All data is saved if there is a power failure.
Terminology
To provide you with a better understanding of the func-
tions of your control unit, the appendix contains the
chapter "Terminology" (see page 23).
Introductory information
Intended use
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Use the adjustment options on the control unit and the
room temperature control unit:
■Do not overheat your rooms; you can save up to 6 %
on your heating costs for every degree you reduce
your room temperature.
Set your room temperature no higher than 20 °C
(see page 11).
■Do not set your DHW temperature too high (see
page 12).
■Select the operating program that meets your current
requirements:
–In the summer, when you don't want to heat any
rooms but do need DHW, select operating program
" " (see page 12).
–If you do not want to heat any rooms and require
no hot water for a prolonged period of time, select
operating program " " (see page 9).
Further recommendations:
■Correct ventilation/airing.
Fully open windows for a short time and close the
thermostatic valves while airing.
■Close roller shutters (if installed) at dusk.
■Set thermostatic valves correctly.
■Never cover radiators or thermostatic valves.
■Controlled DHW consumption: A shower generally
uses less energy than a full bath.
Introductory information
Tips on saving energy
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You can change the settings for your heating system
centrally at the programming unit.
If you have a room temperature control unit installed in
your rooms, you can also change the settings on the
room temperature control unit.
Room temperature control unit operating instruc-
tions
Note
The programming unit can be placed in a wall mount-
ing base. This is available as an accessory. Ask your
heating contractor for more information.
4 8°C
s A
Fig. 1
Takes you one step back in the menu
Cursor keys
Scroll through the menu or adjust values
OK Confirms your selection or setting
No function
Enables you to call up the menu for settings and
scanning
How to use the controls
Standard display
4 8°C
Fig. 2
Press . This takes you to the menu for settings and
scanning.
Symbols
These symbols are not always displayed, but appear
subject to the system version and the operating condi-
tion. Flashing displays indicate that modifications can
be made.
Menu
Central heating
DHW heating
Information
Emissions test mode
Additional settings
Operating program
Frost protection monitoring (standby mode)
DHW heating
Central heating and DHW heating
COMF Comfort mode for DHW heating
ECO Without comfort mode for DHW heating
Messages
Service message
ýThe service interval has expired
Fault message
Fault message for burner
About the controls
Controls
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Displays
Temperature
Frost protection monitoring
Central heating
Heating circuit pump running
Cylinder loading pump running
In conjunction with a solar thermal system:
Solar circuit pump is running
Burner running
Standard factory setting
About the controls
Symbols (cont.)
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0
123
4
bar
C D
E
BA
4 8°C
s A
Fig. 3
AFault indicator (red)
BON indicator (green)
CReset button
DON/OFF switch
EPressure gauge (pressure display)
1. Check the heating system pressure at the
pressure gauge. The system pressure is too low if
the indicator points to the area below 1.0 bar. In this
case, top up with water or notify your local heating
contractor.
2. For open flue operation:
Check that the ventilation apertures of the installa-
tion room are open and unrestricted.
Note
With open flue operation, the combustion air is
drawn from the installation room.
3. Open the gas shut-off valve.
Note
Ask your heating contractor to explain the position-
ing and handling of these components.
4. Switch ON the power supply, e.g. at a separate
MCB/fuse or a mains isolator.
5. Turn ON/OFF switch " " on.
After a short while, the standard display appears
and the green ON indicator illuminates. Your heat-
ing system and room temperature control unit are
now ready for operation.
Shutting down the heating system
With frost protection monitoring
Select operating program " " for frost protection moni-
toring (standby mode).
Press the following keys:
1. for settings; " " flashes.
2. OK to confirm; " " flashes.
3. OK to confirm; " " flashes.
4. until " " flashes.
5. OK to confirm; frost protection is activated.
■No central heating.
■No DHW heating.
■Frost protection for the boiler and the DHW cylinder
is active.
Note
The circulation pumps are briefly started every 24
hours to prevent them from seizing up.
Ending operating program " "
Select another operating program.
Start-up/shutdown
Starting the heating system
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Press the following keys:
1. for settings; " " flashes.
2. OK to confirm; " " flashes.
3. OK to confirm; " " flashes.
4. until " " flashes: The rooms are heated and
DHW is provided.
or
until " " flashes: DHW is heated but central
heating is not active.
5. OK to confirm; the selected operating program is
activated.
Without frost protection monitoring (shutdown)
1. Turn ON/OFF switch " " off.
2. Close the gas shut-off valve.
Note
Ask your heating contractor to explain the position-
ing and handling of these components.
3. Isolate the heating system from its main power sup-
ply, e.g. at the separate MCB/fuse or at a mains
isolator.
4. If outside temperatures of below 3 °C are expected,
please take appropriate measures to protect the
heating system from frost. If necessary, contact
your heating contractor.
Start-up/shutdown
Shutting down the heating system (cont.)
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If you want central heating, check the following points:
■Have you set the required room temperature?
Room temperature control unit operating
instructions
■Have you set the heating flow temperature at a suffi-
ciently high level?
For setting, see the next chapter.
■Have you selected the correct operating program?
For setting see page 11
and
Room temperature control unit operating
instructions
■Have you set the required time program?
Room temperature control unit operating
instructions
Setting the heating flow temperature
Set the heating flow temperature sufficiently high so
the required room temperature can be achieved.
Factory setting: 74 °C
Press the following keys:
1. for settings; " " flashes.
2. OK to confirm; " " flashes.
3. for boiler water temperature; " " flashes.
4. OK to confirm; the selected temperature value
flashes.
5. / for the required boiler water temperature.
6. OK to confirm; the new temperature value is
saved.
Setting the operating program (central heating)
Factory setting: " " for central heating and DHW
heating (winter mode).
Press the following keys:
1. for settings; " " flashes.
2. OK to confirm; " " flashes.
3. OK to confirm.
4. / until " " flashes.
5. OK to confirm; the rooms and DHW are heated.
Stopping the central heating
You do not want to heat any rooms but you want to
heat the DHW.
Press the following keys:
1. for settings; " " flashes.
2. OK to confirm; " " flashes.
3. OK to confirm; " " flashes.
4. until " " flashes.
5. OK to confirm; the central heating is deactivated
and DHW is heated (summer mode).
You do not want to heat any rooms or DHW.
Press the following keys:
1. for settings; " " flashes.
2. OK to confirm; " " flashes.
3. OK to confirm; " " flashes.
4. until " " flashes.
5. OK to confirm; the central heating and DHW heat-
ing are deactivated, frost protection monitoring
is activated (standby mode).
Central heating
Required settings for central heating
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If you want DHW heating, check the following points:
■Have you set the required DHW temperature?
For setting, see the next chapter.
■Have you selected the correct operating program?
For setting, see page 12.
Setting the DHW temperature
Factory setting: 50 °C
Press the following keys:
1. for settings; " " flashes.
2. for " ".
3. OK to confirm; temperature value flashes.
4. / for required DHW temperature.
5. OK to confirm; the new temperature value is
saved.
Setting the operating program (DHW heating)
Factory setting: " " for central heating and DHW
heating (winter mode).
Press the following keys:
1. for settings; " " flashes.
2. OK to confirm; " " flashes.
3. OK to confirm; " " flashes.
4. / until " " flashes for DHW heating (summer
mode, no central heating).
or
until " " flashes for central heating and
DHW heating (winter mode).
5. OK to confirm; the selected operating program is
activated.
Stopping DHW heating
You do not want DHW, but do want to heat the
rooms.
Press the following keys:
1. for settings; " " flashes.
2. OK to confirm; " " flashes.
3. OK to confirm; " " flashes.
4. until " " flashes.
5. OK to confirm; the rooms and DHW are heated
(winter mode).
6. for settings; " " flashes.
7. for " ".
8. OK to confirm; temperature value flashes.
9. to 10 °C.
10. OK to confirm; the new temperature value is
saved.
You do not want to have DHW or heat your rooms.
Press the following keys:
1. for settings; " " flashes.
2. OK to confirm; " " flashes.
3. OK to confirm; " " flashes.
4. until " " flashes.
DHW heating
Required settings (DHW heating)
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5. OK to confirm; DHW heating and central heating
are stopped, frost protection monitoring is acti-
vated (standby mode).
Comfort function (if available)
With the comfort function you can preheat the water
volume in the plate heat exchanger to the selected
DHW temperature. This makes DHW available imme-
diately.
Press the following keys:
1. for settings; " " flashes.
2. for " ".
3. OK to confirm, "COMF ECO" flashes.
4. OK to confirm; "ECO" flashes.
5. for "COMF".
6. OK to confirm; the comfort function is activated.
Ending the comfort function
Press the following keys:
1. for settings; " " flashes.
2. for " ".
3. OK to confirm, "COMF ECO" flashes.
4. OK to confirm; "COMF" flashes.
5. for "ECO".
6. OK to confirm; the comfort function is terminated.
DHW heating
Stopping DHW heating (cont.)
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Factory setting: °C
Press the following keys:
1. for settings; " " flashes.
2. for " ".
3. OK to confirm; " " flashes.
4. / for required temperature unit ("°C" or "°F").
5. OK to confirm; the new temperature unit is saved.
Restoring factory settings
You can simultaneously reset all changed values to the
factory settings.
Press the following keys:
1. for settings; " " flashes.
2. for " ".
3. OK to confirm; " " flashes.
4. OK to confirm; the factory setting is reinstated.
Factory settings:
■Operating program: " "
■Boiler water temperature: 74 °C
■DHW temperature: 50 °C
Further adjustments
Setting the temperature unit (°C/°F)
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Subject to connected components and settings made,
you can call up current temperatures and operating
conditions.
Press the following keys:
1. for settings; " " flashes.
2. for " ".
3. OK to confirm.
4. / for the required information.
5. OK to confirm; if you want to reset the value to "0"
(see following table), " " flashes.
6. OK to confirm; the value is reset.
Example:
On the display, you can see the number "3" which
shows the boiler water temperature. The current boiler
water temperature is 65 °C.
¸
3 6 5°C
Fig. 4
Note
The scan mode terminates automatically after
30 minutes or if you press .
The information appears in the following sequence:
Display Meaning Notes
0 10 LON subscriber no. –
1 15 °C Outside temperature Displayed only if an outside temperature sensor
is connected.
2 95 °C Flue gas temperature –
3 65 °C Boiler water temperature –
4 45 °C Temperature of heating water buf-
fer cylinder or low loss header
Displayed only if a heating water buffer cylinder
or low loss header is connected.
5 50 °C DHW temperature Displayed only if a DHW cylinder is connected.
51 50 °C DHW temperature, top Displayed only if two cylinder temperature sen-
sors are connected.
52 50 °C DHW temperature, bottom
5c 95 °C Collector temperature Displayed only if a Viessmann solar control
module is installed.
5□ 45 °C DHW temperature with solar oper-
ation
Displayed only if a solar thermal system is con-
nected.
53 50 °CTemperature sensor /Displayed only if the Viessmann solar control
module is available and a third temperature sen-
sor has been connected.
54 50 °CTemperature sensor aÖ Displayed only if the Viessmann solar control
module is available and a fourth temperature
sensor has been connected.
6 70 °C Collector temperature Displayed only if a solar thermal system is con-
nected
2 6 3 5 7 2 h Burner hours run Number of hours run (only approximate values).
The hours run can be reset to "0" with "D".
1
0 3 0 5 2 9 Burner starts The number of burner starts can be reset to "0"
with "D".
3
0 0 1 4 1 7 h Solar circuit pump hours run Displayed only if a Viessmann solar control
module is installed.
The hours run can be reset to "0" with "D".
5
0 0 1 4 2 5 Pump starts, solar circuit pump Displayed only if a Viessmann solar control
module is installed.
The pump starts can be reset to "0" with "D".
6
Calling up
Calling up information and resetting values
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Display Meaning Notes
0 0 0 5 0 6 h Hours run, output 22 Displayed only if the Viessmann solar control
module is available and a second circulation
pump has been connected.
The hours run can be reset to "0" with "D".
7
0 0 0 5 0 6 Pump starts, output 22 Displayed only if the Viessmann solar control
module is available and a second circulation
pump has been connected.
The pump starts can be reset to "0" with "D".
8
0 0 2 8 5 0 Solar yield in kWh Displayed only if a Viessmann solar control
module is installed.
The solar energy can be reset to "0" with "D".
9
4 Reception quality Vitocom 100,
type GSM
Displayed only if Vitocom 100, type GSM is con-
nected.
■0 - no reception
■5 - very good reception
1 2
Calling up a service message
Your heating contractor can set a service interval. For
example, burner service after 2500 hours run or serv-
ice after 12 months.
If your heating system is due for a service, the symbol
" " flashes on the display and the expired service
interval is shown.
Example:
Service display with the service interval of 2500 hours
run by the burner:
0
ë
2 5 0h
Fig. 5
Service display with the service interval of 12 months:
1
ë
2
Fig. 6
Notify your local heating contractor and acknowledge
the service message by pressing OK.
Note
If the service can only be carried out at a later point in
time, the service message will reappear after 7 days.
Calling up an acknowledged service message
Press OK for approx. 4 seconds.
Calling up fault messages
If any faults have occurred in your heating system, the
symbol " " flashes on the display and the fault code
is shown. In addition, the red fault indicator flashes
(see page 9).
Calling up
Calling up information and resetting values (cont.)
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Example:
Fault code shown: "50"
1 5 0
ã
Fig. 7
Danger
If faults are not rectified, they can have life
threatening consequences.
Do not acknowledge fault messages several
times in quick succession. If a fault occurs
repeatedly, notify your heating contractor so the
cause can be analysed and the fault rectified.
1. Notify your heating contractor of the fault code. This
enables the heating contractor to be better pre-
pared for the service call and may save additional
travelling costs.
2. Acknowledge the fault message with OK. Symbol
" " no longer flashes.
Note
■If you have connected signalling equipment to
indicate fault messages (e.g. a buzzer), this is
deactivated when the fault message is acknowl-
edged.
■If the fault cannot be fixed until later, the fault
message will reappear the following day.
Calling up an acknowledged fault message
Press OK for approx. 4 seconds.
Note
If there are several fault messages, you can call these
up in sequence by pressing / .
Calling up
Calling up fault messages (cont.)
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In systems with several boilers (multi boiler systems),
each boiler is equipped with its own control unit. These
control units are regulated by a higher control unit.
Make the required settings (e.g. room temperature) at
the higher control unit.
Operating instructions of the higher control unit
Boiler number
In multi boiler systems, each boiler control unit indi-
cates the boiler number on the standard display.
Example:
Boiler number "3"
34 8°C
Fig. 8
Boiler number "3" has been blocked by the higher con-
trol unit.
30
Fig. 9
Operating program
■" " for frost protection monitoring (standby mode):
By selecting operating program " ", you individually
shut down the relevant boiler.
Boiler frost protection monitoring is active.
■" " for DHW heating (summer mode):
You cannot set operating program " ".
Room temperature/boiler water temperature
You cannot select either room temperature or boiler
water temperature.
Multi boiler systems
Special considerations for multi boiler systems
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Activating emissions test mode
Emissions test mode should only be activated by your
flue gas inspector during the annual inspection.
Press the following keys:
1. for settings; " " flashes.
2. for " ".
3. OK to confirm; "ON" flashes.
"FL" appears on boilers with flow rate captur-
ing. Ensure adequate flow rate (e.g. open radi-
ator valves).
4. OK to start the burner for measurement; "ON" will
be displayed constantly.
If "FL" and "p" flash (for boilers with flow
rate capturing), the flow rate is too low. Raise
the flow rate by drawing off heat.
When the flow rate is adequate, "ON" will
flash.
5. OK to start the burner for measurement.
"ON" is constantly displayed.
After 4 s the standard display is shown.
Stopping emissions test mode
Press the following keys:
1. for settings; " " flashes.
2. for " ".
3. OK to confirm; "OFF" flashes.
4. OK to confirm.
Note
Emissions test mode ends automatically after
30 minutes.
Emissions test mode
Activating emissions test mode
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Cause Remedy
The heating system is switched off. ■Turn ON/OFF switch " " on (see page 9).
■Switch ON the mains isolator, if installed (outside the
boiler room).
■Reset the MCB in the power distribution board (main
domestic MCB).
Control unit or room temperature control unit incorrectly
adjusted.
Check settings and correct if required:
■" " must be set (see page 11)
■Room temperature or boiler water temperature (see
page 11)
■Time program
Room temperature control unit operating in-
structions
Only when operating with DHW heating:
DHW priority is enabled (" " is displayed).
Wait until the DHW cylinder has been heated up (" "
symbol disappears).
In the case of operation with an instantaneous water
heater, stop DHW draw-off.
No fuel. With LPG:
Check the fuel reserves and re-order if required.
With natural gas:
Open the gas shut-off valve. If necessary, check with
your gas supply utility.
Symbol " " is shown on the display. Press "R" (see page 9).
Acknowledge the fault message with OK (see page 16).
Notify your heating contractor of the fault code if the
fault recurs.
Symbol " " is shown on the display. Notify your heating contractor of the fault code shown.
Acknowledge the fault message with OK (see page 16).
Rooms are too hot
Cause Remedy
Control unit or room temperature control unit incorrectly
adjusted.
Check settings and correct if required:
■Room temperature or boiler water temperature (see
page 11)
■Time program
Room temperature control unit operating in-
structions
Symbol " " is displayed. Notify your heating contractor of the fault code.
Acknowledge the fault message with OK (see page 16).
There is no hot water
Cause Remedy
The heating system is off. ■Turn ON/OFF switch " " on (see page 9).
■Switch ON the mains isolator, if installed (outside the
boiler room).
■Reset the MCB in the power distribution board (main
domestic MCB).
Control unit incorrectly adjusted. Check settings and correct if required:
■DHW heating must be enabled (see page 12).
■DHW temperature (see page 12).
What to do if...
Rooms are too cold
5592 683 GB