Viessmann Vitoligno 250-S User manual

Operating instructions
for the system user
Viesmann
Wood gasification boiler
for logs up to 50 cm or 100 cm long
VITOLIGNO 250-S
5684 987 GB 6/2015 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.
Appliance connection
■The appliance may only be connected and commis-
sioned by authorised contractors.
■Only operate the appliance with suitable fuels.
■Observe the specified electrical connection require-
ments.
■Modifications to the existing installation may only be
carried out by authorised contractors.
Danger
Incorrectly executed work on the heating system
can lead to life threatening accidents.
Work on electrical equipment must only be car-
ried out by a qualified electrician.
Work on the appliance
■All settings and work on the appliance must be car-
ried out as specified in these operating instructions.
Further work on the appliance may only be carried
out by authorised contractors.
■Never change or remove attachments or fitted
accessories.
■Never open or retighten pipe connections.
Danger
Hot surfaces can cause burns.
Never touch the hot surfaces inside the appli-
ance or those of uninsulated pipes, fittings or
flue pipes.
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
Fire presents a risk of burns and explosion.
■Shut down the heating system.
■Use a tested fire extinguisher, class ABC.
What to do if the heating system develops a fault
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.
Conditions for siting
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
5684 987 GB

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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
The operation of appliances that extract air to the out-
side (cooker hoods, extractors, air conditioning units,
etc.) can create vacuum pressure. If the boiler is oper-
ated 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 the system or affect its function.
Have all installation or replacement work carried
out exclusively by qualified contractors.
Safety instructions
For your safety (cont.)
5684 987 GB

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1. Introductory information Symbols ................................................................................................. 7
Terminology ........................................................................................... 7
Intended use .......................................................................................... 7
Appliance description ............................................................................. 8
Commissioning ...................................................................................... 9
Your system has been preset ................................................................ 9
Energy saving tips ................................................................................. 9
2. About the controls Programming unit .................................................................................. 11
■Help menu .......................................................................................... 11
Standard menu ...................................................................................... 11
Extended menu ...................................................................................... 12
How to use the controls ......................................................................... 13
■Screensaver ....................................................................................... 13
3. Start-up/shutdown Boiler operating phases ......................................................................... 14
■Heat up ............................................................................................... 14
■Load operation .................................................................................... 14
■Residual heat utilisation ...................................................................... 14
■Heating water buffer cylinder draw-off ................................................ 14
Heat-up preparations ............................................................................. 14
Heat-up .................................................................................................. 15
■Opening the hopper cover .................................................................. 15
■Charging with fuel and igniting ........................................................... 16
Recharging fuel ...................................................................................... 17
Steps to take in the event of overheating .............................................. 18
■High limit safety cut-out ...................................................................... 19
■Triggering the function ........................................................................ 19
■Cancelling the function ....................................................................... 19
4. Central heating Room temperature ................................................................................. 20
■Required settings ................................................................................ 20
■Selecting a heating circuit ................................................................... 20
■Setting the standard room temperature .............................................. 20
■Setting the reduced room temperature (night setback) ...................... 21
Operating program ................................................................................. 21
■Setting the operating program for central heating .............................. 21
Time program ........................................................................................ 21
■Setting the time program for central heating ...................................... 21
■Setting time phases ............................................................................ 22
■Deleting a time phase ......................................................................... 22
■Restoring the time phases to the factory settings ............................... 23
Heating curve ......................................................................................... 23
■Adjusting the heating curves .............................................................. 23
Stopping the central heating .................................................................. 24
Comfort function "Party mode" .............................................................. 25
■Selecting "Party mode" ....................................................................... 25
■Terminating "Party mode" ................................................................... 25
Energy saving function "Economy mode" .............................................. 26
■Selecting "Economy mode" ................................................................ 26
■Terminating "Economy mode" ............................................................. 26
Energy saving function "Holiday program" ............................................ 26
■Setting the "Holiday program" ............................................................ 26
■Changing the "Holiday program" ........................................................ 27
■Terminating the "Holiday program" ..................................................... 27
5. DHW heating DHW temperature .................................................................................. 28
■Required settings ................................................................................ 28
■Setting the DHW temperature ............................................................ 28
Index
Index
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Operating program ................................................................................. 28
■Setting the operating program for DHW heating ................................ 28
Time program ........................................................................................ 28
■Setting the time program for DHW heating ......................................... 28
■Setting time phases ............................................................................ 29
■Deleting a time phase ......................................................................... 29
■Resetting time phases to the factory settings ..................................... 29
Stopping DHW heating .......................................................................... 29
6. Further adjustments Setting the display contrast .................................................................... 31
Setting the brightness of the display ...................................................... 31
Assigning names to heating circuits ...................................................... 31
Setting the time and date ....................................................................... 32
Language selection ................................................................................ 32
Setting the temperature unit (°C/°F) ...................................................... 32
Setting the boiler water temperature ...................................................... 33
Adjusting the set value for residual oxygen ........................................... 33
Setting the minimum system temperature ............................................. 33
Restoring factory settings ...................................................................... 33
7. Information call up Calling up information ............................................................................ 35
■Calling up information in the standard menu ...................................... 35
■Calling up information in the extended menu ..................................... 35
■Calling up temperatures ..................................................................... 36
Calling up fault messages ...................................................................... 36
■Displaying a fault message ................................................................. 36
■Calling up a fault message ................................................................. 37
■Calling up an acknowledged fault message ....................................... 37
8. Prolonged heating system
shutdown
Prolonged heating system shutdown ..................................................... 38
Shutdown ............................................................................................... 38
9. Operation with pressure-
jet oil/gas burner (if instal-
led)
Pressure-jet oil/gas burner operation ..................................................... 39
■Retracting the pressure-jet oil/gas burner .......................................... 39
■Starting the pressure-jet oil/gas burner .............................................. 39
■Stopping the pressure-jet oil/gas burner ............................................. 39
■Extending the pressure-jet oil/gas burner ........................................... 39
10. What to do if... Rooms are too cold ................................................................................ 40
Rooms are too hot ................................................................................. 40
There is no hot water ............................................................................. 41
The DHW is too hot ............................................................................... 41
"Fault" is shown in the display ............................................................... 41
is displayed ...................................................................................... 41
11. Maintenance Heating system inspection and maintenance ........................................ 42
■Boiler .................................................................................................. 42
■DHW cylinder (if installed) .................................................................. 42
■Safety valve (DHW cylinder) ............................................................... 42
■Drinking water filter (if installed) ......................................................... 42
Replacing fuses ..................................................................................... 42
Information on cleaning ......................................................................... 42
Maintenance intervals ............................................................................ 43
Cleaning the ash chamber ..................................................................... 44
Cleaning the tubular heat exchanger ..................................................... 45
Emptying the tubular heat exchanger ash pan ...................................... 46
Cleaning the sight glass ......................................................................... 46
Cleaning the combustion chamber ........................................................ 47
12. Ordering fuel Wood fuel ingredients ............................................................................ 48
■Influence of the moisture content ....................................................... 48
Index
Index
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Storage and drying of wood ................................................................... 48
Approved logs ........................................................................................ 48
Approved wood in small pieces ............................................................. 49
Approved fuel for pressure-jet oil burners .............................................. 49
Non-approved fuels ............................................................................... 49
13. Appendix Terminology ........................................................................................... 50
Information on disposal .......................................................................... 51
■Disposal of packaging ........................................................................ 51
■Final decommissioning and disposal of the heating system ............... 51
14. Keyword index ................................................................................................................ 52
Index
Index (cont.)
5684 987 GB

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Symbol Meaning
Reference to other document containing
further information
1.
Step in a diagram:
The numbers correspond to the order in
which the steps are carried out.
Warning of material losses and environ-
mental pollution
Live electrical area
Pay particular attention.
■Component must audibly click into place.
or
■Acoustic signal
■Fit new component.
or
■In conjunction with a tool: Clean the sur-
face.
Dispose of component correctly.
Dispose of component at a suitable collec-
tion point. Do not dispose of component in
domestic waste.
Terminology
To provide you with a better understanding of the func-
tions of your boiler some terminology is explained.
The terms are marked as follows:
Further information can be found in chapter
"Terminology" in the appendix.
Intended use
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 heating
water that is of potable water quality.
Intended use 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 shall be deemed
inappropriate.
Any usage beyond this must be approved by the man-
ufacturer in each individual case.
Introductory information
Symbols
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Incorrect usage or operation of the appliance (e.g. the
appliance being operated for longer periods when
open) is prohibited and will result in an exclusion of lia-
bility. Incorrect usage also occurs if the components in
the heating system are modified from their intended
use (e.g. if the flue gas and ventilation air paths are
sealed) or if other fuels than those intended for this
appliance are used.
Appliance description
The Vitoligno 250-S is suitable for the combustion of
logs with a moisture content of 15 to 20 %, as well as
pieces of residual wood, wood briquettes and residual
wood with shavings. Approved fuels are described in
the chapter entitled "Ordering fuel", see page 48.
Note
If the moisture content is greater than 20 %, this can
lead to energy losses and contamination of the boiler
and flue system.
As an additional option to heating with wood, a pres-
sure-jet oil or gas burner can be fitted to the boiler.
Overview of components
D
E
F
AB
G
C
Fig. 1
ACleaning cover, heat exchanger
BSight glass
CHopper cover
DHopper
ECombustion chamber maintenance cover / con-
nection for pressure-jet oil / gas burner
FCleaning door
GAsh chamber door
Note
E is located on the right and left hand side of the
boiler.
Introductory information
Intended use (cont.)
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Commissioning and matching up of the control unit to
local conditions and the structural characteristics of the
building must be carried out by your heating contractor.
Installation and service instructions
As the user, you may be obliged to notify your local
flue gas inspector of the installation of new combustion
equipment [check local regulations]. Your local flue gas
inspector (where applicable) will also provide you with
information on additional tasks concerning your com-
bustion equipment (e.g. regular testing, cleaning, etc.).
Your system has been preset
Your boiler's control unit is set at the factory.
■The heating circuits are set to the operating program
"Heating".
■The domestic hot water heating is set to the operat-
ing program "DHW".
Your heating system is therefore ready for use:
Central heating
■Your rooms are heated from 06:00 to 22:00 h, to a
"Set room temp" of 22 °C (standard heating mode).
■From 22:00 to 06:00 h, your rooms are heated to the
"Set red room temp" (room temperature for
reduced heating mode, night setback).
■Your heating contractor can make further settings for
you during commissioning.
You can change any settings at any time to suit your
individual requirements (see from page 20).
DHW heating
■The DHW is heated to 60 °C "Set DHW tempera-
ture" every day from 00:00 to 24:00 h.
■Your heating contractor can make further settings for
you during commissioning.
You can change any settings at any time to suit your
individual requirements (see from page 28).
Wintertime/summertime changeover
■This changeover is automatic.
Time and date
■The day and time were set by your heating contrac-
tor during commissioning.
Power failure
■All data is retained if there is a power failure.
Energy saving tips
Use the adjustment options offered by your boiler con-
trol unit:
■For central heating, select the operating program
that meets your current requirements:
–For short periods of absence (a few hours, such as
for shopping trips), select "Economy mode" (see
page 26).
The room temperature is reduced for as long as
economy mode is activated.
–If you are going away, select the "Holiday pro-
gram" (see page 26).
The operating program for central heating is auto-
matically set to "Standby mode" while the holiday
program is active.
–If you do not want to heat the rooms and you do
not require DHW for an extended period, select the
"Standby mode" operating program for the rele-
vant heating circuits and for DHW.
–See page 24 for the relevant heating circuits
–See page 29 for DHW heating
■Never set the DHW cylinder temperature excessively
high (see page 28).
You can further save energy by taking the following
steps:
Introductory information
Commissioning
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AC
E
B
D
Fig. 2
■Correct ventilation/airing:
Open windows A wide for a short time. During this
time, close thermostatic valves B.
■Do not overheat the rooms; aim for a room tempera-
ture of 20 °C. Every degree of room temperature
reduction saves up to 6 % on your heating bills.
■Close shutters (where installed) on the windows at
dusk.
■Ensure that thermostatic valves B are properly
adjusted.
■Never cover or obstruct radiators C or thermostatic
valves B.
■Make use of the setting options of control unit D,
e.g. "standard room temperature" alternating with
"reduced room temperature".
■Set the DHW temperature of DHW cylinder E at
control unit D.
■Only enable the DHW circulation pump (via switching
times at the control unit) when DHW is being drawn
off.
■Check your hot water consumption: A shower
requires less energy than a full bath.
Introductory information
Energy saving tips (cont.)
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Buffer
Heating
DHW
Boiler
Buffer drawing
Select with (
B
A
Fig. 3
ADisplay of operating phase
BDialogue line
Takes you to the previous step in the menu or can-
cels a setting that has been started.
Cursor keys
Scrolls through the menu or adjusts values.
dConfirms your selection or saves your setting.
Calls up the help text relevant to the selected
menu point.
Calls up the extended menu.
The selected menu point is highlighted in white.
Dialogue line B shows instructions on what to do.
There are 2 control levels available, the standard
menu and the extended menu.
Help menu
You are provided with an quick guide explaining the
controls and information about heating circuit selec-
tion.
Call up the quick guide as follows:
■From anywhere in the menu:
Call up the "Help" menu point by pressing "?".
Standard menu
Buffer
Heating
DHW
Boiler
Buffer drawing
Select with (
Fig. 4
You can call up the settings you require most fre-
quently from the standard menu:
■Selecting the set room temperature
■Selecting an operating program
■Selecting the comfort function "Party mode"
■Selecting the energy saving function "Economy
mode"
■Calling up the operating status
■Checking temperatures, e.g. outside temperatures
■Calling up information
■Calling up warning, fault and information messages
Call up the standard menu as follows:
■If the screensaver is active:
Press any key.
■From anywhere in the menu:
Keep pressing until the standard menu appears.
About the controls
Programming unit
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Menu
Select with (
Boiler
Information
Heating
DHW
Fig. 5
In the extended menu, you can call up and adjust the
settings of the control unit's range of less frequently
used functions, such as the holiday program and time
programs for example.
Call up the extended menu as follows:
■If the screensaver is active:
Press any key followed by .
■From anywhere in the menu:
Press .
About the controls
Extended menu
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Example: Procedure for settings with different dialogue lines
Vv
or
OK
Ú
OK OK
OK
DHW
Additional boiler
Information
48°C
Heating
Boiler water temp
Select with (
OK
Heating circuit 1
Operating program
Party mode
Economy mode
20°C
ÙÚ
Set room temperature
HC1
ÙÚ
HC1
Select with (
Heating circuit 2
Operating program
Party mode
Economy mode
20°C
ÙÚ
Set room temperature
HC2
ÙÚ
HC2
Select with (
Heating circuit 1
Operating program
Party mode
Economy mode
22°C
ÙÚ
Set room temperature
HC1
Heating circuit selection ÙÚ
HC2
Was selected
Heating circuit 2
Set room temperature HC1
20°C
Change with (
Set room temperature HC1
22°C
Adopt with OK
Set room temperature HC1
22°C
Adopted
Select with (
22°C
Fig. 6
Screensaver
■The screensaver will become active if you have not
adjusted any settings on the programming unit for a
few minutes.
■Depending on the operating phase, the screensaver
will show information on the current values of the
boiler or heating water buffer cylinder.
Press any key. This takes you to the standard menu
(see page 11).
About the controls
How to use the controls
5684 987 GB

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The operating phases are shown on the programming
unit display. After heat up, the boiler runs through the
following operating phases in sequence:
■Heat up
■Load operation
■Residual heat utilisation
■Buffer drawing
Heat up
After charging and igniting the fuel, the boiler starts up.
Initially, the boiler air dampers are adjusted.
Load operation
From a flue gas temperature above 120 °C or a resid-
ual oxygen content below 15 % (for 2 minutes), the
boiler enters control mode. For this, the residual oxy-
gen content is monitored and the air dampers are con-
tinuously regulated to achieve the set value.
The fuel in the boiler is fully combusted while transfer-
ring the rated heating output to the heating circuits and
the heating water buffer cylinder.
Residual heat utilisation
After combustion of the fuel, the boiler is still warm.
During this phase, the residual heat of the boiler water
is used to supply the heating circuits and DHW heat-
ing. When the temperature of the boiler water is no
longer sufficient for this, the required heat is drawn
from the heating water buffer cylinder. This is achieved
by using the buffer cylinder control valve and provides
up to 9 % increased heat energy yield for the boiler.
Heating water buffer cylinder draw-off
The temperature of the boiler water is too low to supply
the heating circuits and DHW heating with heat. They
are now supplied exclusively from the heating water
buffer cylinder.
Heat-up preparations
Fig. 7
1. Check the heating system pressure at pressure
gauge A:
If the indicator is resting below the red field, the
system pressure is too low. Top up with water or
notify your local heating contractor.
Minimum system pressure: 1.0 bar (0.1 MPa)
2. Check that the vents in the installation room are
unrestricted.
Note
With open flue operation, the combustion air is
drawn from the installation room.
3. Check that the heating system or the heating water
buffer cylinder can draw off heat. Where necessary,
open the thermostatic valves.
Start-up/shutdown
Boiler operating phases
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4. Check that the heating system has been vented.
5. Ensure that all shut-off gate valves to the heating
flow and return are open.
6. Check that all doors and covers on the boiler are
closed.
7. Ensure that all ball valves for the return tempera-
ture raising facility are open.
8. Ensure that power is supplied to the boiler.
!Please note
Risk of damage to the pressure-jet oil/gas
burner (if installed) when operating the boiler
with logs.
Ensure that the pressure-jet oil/gas burner
has been extended prior to operation with
logs.
Heat-up
Before heating up: Check that all required conditions
have been met. See chapter "Heat-up preparations"
from page 14.
Opening the hopper cover
Danger
Deflagration and poisonous flue gases can
cause serious injuries.
Never open the hopper cover in any operating
phase until the flue gas temperature has fallen
below 120 °C or 248 °F.
Danger
Poking around in the firebed leads to oxygena-
tion, which can produce a flash.
Never poke around in the firebed.
A
B
Fig. 8
1. Initially open the hopper cover to lock A.
2. Turn mushroom handle B to unlock the hopper
cover and fully open the cover.
Start-up/shutdown
Heat-up preparations (cont.)
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Charging with fuel and igniting
Important information
■Charge with fuel according to the heat demand.
■Fill the hopper completely if the outside temperature
is low and the heating water buffer cylinder is cold. In
spring and autumn, only charge as much fuel as
required for the actual heat demand and buffer vol-
ume.
■Before starting up the boiler, ensure that the amount
of heat generated can be drawn off and stored by the
heating system. If the amount of heat produced can-
not be drawn, the boiler will overheat and the high
limit safety cut-out will respond. The boiler is then
cooled with cold tap water via the safety heat
exchanger and heating energy is lost.
Danger
The wrong kind of fuel during heat up encour-
ages the formation of low temperature carboni-
sation gases in the hopper and can result in def-
lagration.
Never place pieces of residual wood, shavings,
sawdust, woodchips, wood briquettes or residual
wood with shavings directly onto the grate.
!Please note
If the boiler is charged incorrectly with pieces of
residual wood, wood briquettes and residual
wood with shavings it may be damaged.
1. Fill the hopper with logs up to at least one
third of its capacity.
This is achieved when the fireclay bricks in
the combustion chamber are no longer visible
and the grate is fully covered with logs.
2. Do not charge with other fuels before this is
achieved.
E
A
B
C
D
Fig. 9
ACharcoal remains
BPaper, cardboard
CPieces of wood
DLogs
EHopper cover
01. Remove fine ash from the hopper. Use a scraper
to push the fine ash into the ash pan.
02. !Please note
If the logs are too big, they will impair the
function of the boiler and may damage it.
Take the depth of the hopper and size of the
hopper cover into account when selecting
logs. Never exceed the maximum log length
(see page 48).
Place paper, cardboard B and easily combustible
kindling C on charcoal remains A.
Note
The layer should be roughly 25 cm thick and
should cover the entire grate.
03. Place logs D in the hopper so they are horizontal
and densely packed across the entire width of the
boiler.
04. Remove any dirt that may be present on the seat-
ing faces of hopper cover E.
Start-up/shutdown
Heat-up (cont.)
5684 987 GB

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05. Close hopper cover E.
Note
Ensure that the safety latch engages and that the
hopper cover is securely closed.
06.
Fig. 10
Open the ash chamber door.
07. Danger
Risk of severe injuries due to highly-flam-
mable materials when igniting the fuel.
Never use highly-flammable substances
such as petrol, oil, alcohol or solvents to
ignite the fuel.
Ignite the paper across the entire width of the hop-
per.
Note
This allows the flames to spread quickly across
the entire grate area. A quick heat up means per-
fect combustion is quickly achieved.
08. Switch the boiler on at the control unit. Press the
"START/STOP" button.
09. Now swivel the ash chamber door down and leave
it open about 10 cm.
10. Supervise the heating system during the heat-up
phase until a flue gas temperature of 110 °C is dis-
played.
Note
To display the flue gas temperature, call up the
"Boiler" menu item in the standard menu.
11. Close the ash chamber door as soon as the flue
gas temperature has reached 110 °C.
Note
Ensure that all covers and doors are tightly shut
during operation. This safeguards optimum com-
bustion.
Recharging fuel
Note
When charging with pieces of residual wood, wood bri-
quettes and residual wood with shavings, logs should
be regularly added. This ensures better combustion.
A full hopper charge will provide a combustion period
of 3 - 4 hours, depending on the amount of heat being
drawn off and the quality of the fuel.
Flue gas temperature > 120 °C < 120 °C to > 60 °C < 60 °C
Steps to take Do not recharge with fuel. Recharge with fuel. Repeat the heat up proc-
ess. See page 16.
Danger
Flue gas escaping via the hopper cover poses a
risk to health and the environment.
Wait until the temperature of the flue gas has
dropped below 120 °C before opening the hop-
per cover briefly to recharge with fuel.
Start-up/shutdown
Heat-up (cont.)
5684 987 GB

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A
B
Fig. 11
1. Press the "START/STOP" button.
The flue gas fan starts up.
2. Initially open the hopper cover to lock A.
3. Wait a short while to allow the low temperature car-
bonisation gas to be drawn out of the hopper.
4. Turn mushroom handle B clockwise to unlock the
hopper cover. Fully open the cover.
5. Check the fuel level and the height of the glowing
embers.
If there are only glowing embers present, continue.
6. Danger
Recharging the fuel too slowly, recharging
large amounts of logs or recharging with
pieces of residual wood encourages the for-
mation of low temperature carbonisation
gases in the hopper and can result in defla-
gration.
■Recharge wood swiftly.
■Never place pieces of residual wood, shav-
ings, sawdust, woodchips, wood briquettes
or residual wood with shavings directly onto
the glowing embers.
!Please note
If the logs are too big, they will impair the
function of the boiler and may damage it.
Take the depth of the hopper and size of the
hopper cover into account when selecting
logs. Never exceed the maximum log length
(see page 48).
Quickly recharge with fuel according to the current
heat demand.
7. Open the ash compartment cover if required.
This supports the combustion process. We recom-
mend this procedure if the flue gas temperature is
below 120 °C.
8. Close the hopper cover.
Steps to take in the event of overheating
The high limit safety cut-out protects your boiler from
overheating.
Note
Modifications to this component are prohibited and will
render all warranties void.
Replace faulty components only with genuine spare
parts from Viessmann.
Note
If the boiler overheats again after a short time or over-
heats regularly, notify your heating contractor.
Start-up/shutdown
Recharging fuel (cont.)
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19
High limit safety cut-out
Fig. 12
Reset button A of the high limit safety cut-out is loca-
ted on the front of the boiler.
Triggering the function
If the boiler water temperature exceeds 95 °C the high
limit safety cut-out responds.
Note
The high limit safety cut-out can only be reset man-
ually.
Cancelling the function
Note
The high limit safety cut-out can only be reset
(unlocked) once the boiler water temperature has
reached approx. 70 °C.
After each triggering of the high limit safety cut-out,
check that the thermally activated safety valve is reset.
1. Unscrew protective cap A.
2. Press the green button on the high limit safety cut-
out.
A faint "click" will be audible, the high limit safety
cut-out is reset.
3. Acknowledge the excess temperature on the pro-
gramming unit of the control unit with d.
4. Refit protective cap A over the green button.
Start-up/shutdown
Steps to take in the event of overheating (cont.)
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20
Required settings
If you require central heating, check the following
points:
■Have you selected the heating circuit?
For information on settings, see chapter "Selecting a
heating circuit" on page 20.
■Have you set the required room temperature?
For information on settings, see page 20.
■Have you selected the correct operating program?
For information on settings, see page 21.
■Have you selected the required time program?
For information on settings, see page 21.
Selecting a heating circuit
If required, the heating of your interior can be split over
several heating circuits.
■In the case of heating systems with several heating
circuits always first select the heating circuit where
you want to make a change, before inputting any set-
tings.
■This selection is not possible in heating systems with
only one heating circuit.
Example:
■"Heating circuit 1" is the heating circuit for the
rooms occupied by you.
■"Heating circuit 2" is the heating circuit for the
rooms of a separate apartment.
Ú
Htg circuit selection HC2
Was selected
Heating circuit 2
Heating circuit 1 HC1
Economy mode
Select with (
Party mode
Heating program
Set room temp.
ß
21 °C
ÙÚ
HC2
ÙÚ
HC1
Fig. 13
The heating circuits are marked at the factory as
"Heating circuit 1" (HC1) and "Heating circuit 2"
(HC2).
If you or your heating contractor have renamed the
heating circuits (e.g. as "Apartment" or similar), that
title is then displayed instead of "Heating circuit 1"
(see page 31).
Setting the standard room temperature
Press the following keys:
1. äRepeatedly, until the standard menu is dis-
played.
2. |/~To select "Heating".
3. dTo confirm.
4. Ù/ÚTo select "Heating circuit 1" (HC1), "Heat-
ing circuit 2" (HC2) or "Heating circuit 3"
(HC3).
5. |/~For "Set room temp".
6. dTo confirm.
7. |/~For the required temperature.
8. dTo confirm.
"Adopted" appears briefly on the display.
Central heating
Room temperature
5684 987 GB