Viessmann VITOTRONIC 100 User manual

Operating Instructions
for use by heating contractor
5693 971 - 03 03/2015
Read and save these instructions
for future reference.
Vitotronic 100, type GC1B
Heating system with control unit for constant temperature operation
for use with boiler models VD2A, VD2 and CT3
VITOTRONICr100
Please file in Service Binder
Certified as a component
part for Viessmann boilers
IMPORTANT
Product may not be exactly as shown

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Vitotronic 100, GC1B Operating
General
Safety, Installation and Warranty Requirements
Please ensure that these instructions are read and understood before commencing installation. Failure to comply with
the instructions listed below and details printed in this manual can cause product/property damage, severe personal
injury, and/or loss of life. Ensure all requirements below are understood and fulfilled (including detailed information
found in manual subsections).
WARNING
Installers must follow local regulations with respect to
installation of carbon monoxide detectors. Follow the
Viessmann maintenance schedule of the boiler contained
in this manual.
Product documentation
Read all applicable documentation before commencing
installation. Store documentation near boiler in a
readily accessible location for reference in the future
by service personnel.
For a listing of applicable literature,
please see section entitled “Important
Regulatory and Safety Requirements”.
Warranty
Information contained in this and
related product documentation must
be read and followed. Failure to do
so renders the warranty null and void.
Licensed professional heating contractor
The installation, adjustment, service and maintenance
of this equipment must be performed by a licensed
professional heating contractor.
Please see section entitled
“Important Regulatory and Installation
Requirements”.
Advice to owner
Once the installation work is complete, the heating
contractor must familiarize the system operator/
ultimate owner with all equipment, as well as safety
precautions/requirements, shutdown procedure, and
the need for professional service annually before the
heating season begins.
Operating and Service Documentation
It is recommended that all product documentation such as
parts lists, operating and service instructions be handed
over to the system user for storage. Documentation is to
be stored near boiler in a readily accessible location for
reference by service personnel.

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Vitotronic 100, GC1B Operating
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 safety regulatory inspector
of the installation [check local regulations]. Your local
safety regulatory inspector will also inform you [where
appropriate] about work he may be required to perform
on your combustion equipment (e.g. regular checks,
cleaning).
Your System is Preset at the Factory
The control unit is preset to “ w “ at the factory for
central heating and DHW heating.
Your heating system is therefore ready for operation:
Central Heating
The rooms are heated in accordance with the settings
on your control unit and room temperature control 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 heating”).
DHW Heating
The DHW is heated up to 122°F (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 heating”).
Frost Protection
Your boiler and DHW tank are protected against frost.
Power Failure
All data is saved if there is a power failure.
General
Special Considerations for Multi Boiler Systems
The Vitotronic 100 can be used in the following systems:
Single boiler systems
Multi boiler systems with a Viessmann cascade control
unit
Multi boiler systems of a higher third party control unit
In multi boiler systems (systems with several boilers),
each boiler is equipped with its own control unit. These
control units are regulated by the higher control unit.
Make the required settings (e.g. set room temperature)
at the higher control unit.
DHW heating can only be selected at the higher control
unit.
Operating Instructions of the higher control unit.
Note: These operating instructions do not apply
in conjunction with multi boiler systems.
To provide you with a better understanding of the
functions of your control unit, the appendix contains
the chapter “Terminology” (see page 18).
Terminology

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Vitotronic 100, GC1B Operating
Page
Table of Contents
General
Safety
Operation
Start-up/Shutdown
Central Heating
DHW Heating
Further Adjustments
Scanning
Troubleshooting
Maintenance
Terminology
Safety, Installation and Warranty Requirements..............2
Commissioning..........................................................3
Your System is Preset at the Factory.............................3
Special Considerations for Multi Boiler Systems..............3
Terminology..............................................................3
For your Safety..........................................................5
Controls....................................................................6
Where to Find the Controls..........................................6
How to Use the Controls.............................................6
Symbols on the Display...............................................7
Starting the Heating System.........................................8
Shutting Down the Heating System..............................8
Selecting the Set Boiler Water Temperature...................9
.
Setting the Heating Program (Central Heating)...............9
Stopping Central Heating............................................9
Required Settings (DHW Heating)................................10
Setting the DHW Temperature....................................10
Setting the Heating Program (DHW Heating)................10
Stopping DHW Heating..............................................10
Setting the Temperature Unit (°C/°F)..........................11
Restoring Factory Settings.........................................11
Scanning Information.................................................12
Scanning the Service Messages..................................13
Scanning Fault Messages...........................................14
Emissions Test Mode................................................14
Rooms are Too Cold.................................................15
Rooms are Too Hot...................................................15
There is No Hot Water...............................................16
The DHW is Too Hot.................................................16
“
“ Flashes on the Display ........................................16
“ ” Flashes on the Display ........................................16
Maintenance............................................................17
Terminology.............................................................18

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Vitotronic 100, GC1B Operating
If you smell gas
HDon’t smoke! Don’t use naked flames or cause sparks
(e.g. by switching lights or electrical appliances on
and off)
HOpen windows and doors
HClose the gas shut-off valve
HInform your heating engineers/service contractors from
outside the building
HObserve the safety regulations of your gas supply
company (see gas meter) and those of your heating
engineers (see start-up or installation report).
In emergencies
HImmediately switch off the power supply, e.g. at the
separate fuse or power supply disconnect switch
(unless there is a smell of gas).
HClose the shut-off valves in the oil pipes or close the
gas shut-off valve, whichever applicable.
HUse suitable extinguishers in the event of fire.
Installation of additional components
The installation of additional components which have not
been tested together with the boiler can adversely affect
the function and performance of the boiler.
Our warranty does not cover and we accept no liability
for damage attributable to the installation of such
components.
Boiler room conditions
HDo not use a room in which the air is polluted by
halogenated hydro-carbons (e.g. as contained in
aerosols, paints, solvents and cleaning agents)
HDo not use a room subject to high levels of dust
HDo not use a room subject to permanently high humidity
HThe room should be frost-protected
HMax. ambient temperature 95°F (35°C).
HProvide good ventilation and do not close or obstruct
vents (if installed).
CAUTION
Follow these safety instructions closely to avoid the risk
of injury and damage to property.
For your Safety
HOperation
Before operating the boiler, make sure you fully
understand its method of operation. Your heating
contractor should always perform the initial start-up
and explain the system. Any warranty is null and void
if these instructions are not followed.
HFlue gas smell
- Deactivate heating equipment.
- Open windows and doors.
- Inform your heating contractor.
HWorking on the equipment
All personnel working on the equipment or the heating
system must have the proper qualifications and hold
all necessary licenses. Ensure main power to
equipment, heating system, and all external controls
has been deactivated. Close main gas supply valve.
Take precautions in all instances to avoid accidental
activation of power during service work.
HDangerous conditions
- Deactivate main power immediately.
- Close gas supply valve.
HMaintenance and cleaning
Regular inspection and service by a qualified heating
contractor is important to the performance of the boiler.
Neglected maintenance impacts on warranty; regular
inspection ensures clean, environmentally friendly and
efficient operation. We recommend a maintenance
contract with a qualified heating contractor.
HTechnical Data Manual
- Installation Instruction and Service Instructions
- Operating Instructions and User’s Information Manual
Additional applicable literature:
- Accessory manuals
Safety

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Vitotronic 100, GC1B Operating
Controls
Operation
The settings required for operating your heating system
are made on the Vitotronic 100, GC1B.
Opening the Control Unit
The control unit is behind the hinged cover. The hinged
cover is opened by pulling the top gently downwards
towards you.
You must close the hinged cover again after use.
ACover
Programming Unit
Takes you to the previous step in the menu or cancels
a setting that has been started.
Cursor keys (to scroll through the menu or to set values).
OK Confirms your selection or saves the setting.
? No function.
Enables you to call up the menu for settings and scanning.
Standard Display
Press .
This takes you to the menu for settings and scanning.
How to Use the Controls
Where to Find the Controls
Each boiler is equipped with its own control unit for
constant temperature operation.
HControl unit for cascade operation on the boiler:
Vitotronic 100, GC1B
You can change all settings for your heating system
centrally at the control unit programming unit.
The settings at the Vitotronic 100, GC1B are described in
these operating instructions.

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Vitotronic 100, GC1B Operating Operation
These symbols are not always displayed, but appear
subject to the system version and the operating state.
Flashing displays indicate that modifications can be made.
Menu
Settings for heating
w Setting the DHW temperature
Scanning information
Further settings
S Emissions test mode
Heating Program
9Standby mode with frost protection monitoring
w DHW heating only
w Central heating and DHW heating
Messages
Service message
 Fault message
Displays
t Temperature
pCirculation pump at output 20 running
p
w DHW pump running
pIn conjunction with a solar thermal system:
Solar circuit pump running
A Burner in operation
D Factory settings
Symbols on the Display

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Vitotronic 100, GC1B Operating
Starting the Heating System
Start-up/Shutdown
Legend
AON indicator (green)
BFault indicator (red)
CEmissions test switch
(only for service purposes)
DTest key
(only for service purposes)
EFixed high limit reset
FON/OFF switch
GAdjustable high limit
HFuses
Controls With Open Cover
For cover, see page 6.
Ask your heating contractor about the following:
Boiler and relevant control unit type
System operating pressure
Position of the pressure gauge, shutoff valves, gas
shut-off valve (combustion air device operation).
1. Check the heating system pressure at the pressure
gauge. If the pressure of the heating system is too low,
top up the water or notify your heating contractor.
2. Open the shut-off valves in the oil lines (at the tank
and filter) or open the gas shut-off valve.
3. Switch ON the power supply, e.g. at a separate MCB/
fuse or a mains isolator.
4. Switch the ON/OFF switch ON.
After a short time, the standard display appears and
the green ON indicator illuminates. The heating system
is now ready for operation.
Shutting Down the Heating System
With Frost Protection Monitoring
Select the heating program “9“ for standby mode
(with frost protection monitoring).
Press the following keys:
1. for settings; “ “ flashes.
2. OK to confirm; “9
w “ flashes.
3. OK to confirm; the currently selected heating
program flashes.
4.

until “9“ flashes.
5. OK to confirm.
No central heating
No DHW heating
Frost protection for the boiler and the DHW tank is
enabled
Pump exercise function
Circulation pumps are started for 10 sec. once every 24
hours to prevent the pumps from seizing up. This function
is active during all operating programs and during warm
weather shutdown.
Ending heating program “9“
Select another heating program.
Without Frost Protection Monitoring (Shutdown)
1. Switch the ON/OFF switch OFF.
2. Close the shut-off valves in the oil lines (at the tank
and filter) or close the gas shut-off valve.
3. Isolate the heating system from its main power supply,
e.g. at a separate MCB/fuse or a mains isolator.
4. Where outside temperatures of below 37°F (3°C) are
anticipated, please take suitable measures to protect
the heating system against frost. If necessary, contact
your heating contractor.
Information on a Prolonged Shutdown:
Circulation pumps may seize up as they are not supplied
with power.

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Vitotronic 100, GC1B Operating
Selecting the Set Boiler Water Temperature
Select a sufficiently high set boiler water temperature
(heating supply temperature) so that the required room
temperature can be achieved.
Factory setting: 167°F (75°C).
Central Heating
Setting the Heating Program (Central Heating)
Stopping the Central Heating
Factory setting: “ w “ for central heating and DHW
heating (winter mode).
Press the following keys:
1. for settings; “ “ flashes.
2. OK to confirm; “9
w “ flashes.
3. OK to confirm; the currently selected heating
program flashes.
4. until “
w “ flashes (summer mode, no central
heating)
or
until “9“ flashes
(standby with frost protection monitoring).
5. OK to confirm.
Press the following keys:
1. for settings; “ “ flashes.
2. OK to confirm; “9
w “ flashes.
3. for set boiler water temperature; “
t “ flashes.
4. OK to confirm; the selected temperature value flashes.
5.
for the required set boiler water temperature.
6. OK to confirm; the new temperature value is saved.
Press the following keys:
1. for settings; “ “ flashes.
2. OK to confirm; “9
w “ flashes.
3. OK to confirm.
4. until “
w “ flashes.
5. OK to confirm; the rooms are heated and DHW
is provided.

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Vitotronic 100, GC1B Operating
Required Settings (DHW Heating)
If you require DHW heating, check the following points:
Have you set the required DHW temperature?
For settings, see ‘Setting the DHW Temperature’.
Have you set the correct heating program?
For settings, see ‘Setting the heating program (DHW
heating)’.
Press the following keys:
1. for settings; “ “ flashes.
2. until “
w “ flashes.
3. OK to confirm; temperature value flashes.
4. for required DHW temperature.
5. OK to confirm; the new temperature value is saved.
Setting the DHW Temperature
Setting the Heating Program (DHW Heating)
Press the following keys:
1. for settings; “ “ flashes.
2. OK to confirm; “9
w “ flashes.
3. OK to confirm; the currently selected heating
program flashes.
4. until “
w “ flashes for DHW heating
(summer mode, no central heating)
or
until “ w “ flashes for central heating and DHW
heating (winter mode).
5. OK to confirm; the selected heating program
is activated.
DHW Heating
Factory setting: 122°F (50°C).
Factory setting: “
w “ for central heating and DHW
heating (winter mode).
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; “9
w “ flashes.
3. OK to confirm; the currently selected heating
program flashes.
4. until “
w “ flashes.
5. OK to confirm.
6. for settings; “ “ flashes.
7. until “
w “ flashes.
8. OK to confirm; temperature value flashes.
9. until 50°F (10°C) is displayed.
10. OK to confirm; the new temperature value is saved.
You do not want to have DHW or heat the rooms.
Press the following keys:
1. for settings; “ “ flashes.
2. OK to confirm; “9
w “ flashes.
3. OK to confirm; the currently selected heating
program flashes.
4.

until “9“ flashes.
5. OK to confirm; DHW heating and central heating are
stopped, frost protection monitoring is activated
(standby mode).

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Vitotronic 100, GC1B Operating
Setting the Temperature Unit (°C/°F)
Press the following keys:
1. for settings; “ “ flashes.
2. until “ “ flashes.
3. OK to confirm; “
D “ flashes.
4. for required temperature unit (“°C” or “°F”).
5. OK to confirm; the new temperature unit is saved.
Further Adjustments
Press the following keys:
1. for settings; “ “ flashes.
2. until “ “ flashes.
3. OK to confirm; “
D “ flashes.
4. OK to confirm; the factory setting is reinstated.
Factory settings:
Heating program: “ w “
Temperature unit: °C
Set boiler water temperature: 167°F (75°C)
Set DHW temperature: 122°F (50°C)
Restoring Factory Settings
You can simultaneously reset all changed values to the
factory settings.
Factory setting: °C.

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Scanning Information
Scanning
Subject to the connected components and settings
made, you can scan current temperatures and operating
conditions.
Press the following keys:
1. for settings; “ “ flashes.
2. until “ “ flashes.
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), “
D “ flashes.
6. OK to confirm; the value is reset.
The information appears in the following sequence:
Display Explanation Notes
0 1 LON participant number Control unit has participant number 1
2 225°F (107°C) Flue gas temperature Displayed only if a flue gas temperature sensor is connected
3 149°F (65°C) Boiler water temperature -
4 136°F (58°C) Temperature low loss header Displayed only if a low loss header is connected
5 122°F (50°C) DHW temperature
(only in conjunction with
one DHW tank temperature
sensor)
Displayed only if a DHW tank temperature sensor is connected
51 113°F (45°C) DHW temperature, DHW tank
temperature sensor 1
Displayed only in conjunction with two DHW tank temperature
sensors
52 113°F (45°C) DHW temperature, DHW tank
temperature sensor 2
Displayed only in conjunction with two DHW tank temperature
sensors
5 113°F (45°C) DHW temperature with solar
operation
Displayed only if a solar thermal system is connected
53 122°F (50°C) Temperature sensor /Displayed only if a Viessmann solar control module (SM1) is
installed and the third temperature sensor is connected
54 122°F (50°C) Temperature sensor aÖ Displayed only if a Viessmann solar control module (SM1) is
installed and the fourth temperature sensor is connected
5 158°F (70°C) Collector temperature Displayed only if a solar thermal system is connected
6 131°F (55°C) Temperature sensor aJAOnly if a sensor is connected
7 131°F (55°C) Temperature sensor aJBOnly if a sensor is connected
2 6 3 5 7 2 h
1
Hours run, burner single
stage, stage 1 or modulating
The value can be reset to “0” with “
D ”
2 6 3 5 7 2 h
2
Hours run, burner stage 2 The value can be reset to “0” with “
D ”
0 1 3 5 7 8
3
Burner starts The number of burner starts can be reset to “0” with “
D ”
0 0 1 2 2 5
4
Fuel consumption The value can be reset to “0” with “
D ”
0 0 1 4 1 7 h
5
Solar circuit pump hours run Displayed only if a Viessmann solar control module (SM1) is
installed. The value can be reset to “0” with “
D ”
0 0 1 4 2 5
6
Pump starts, solar circuit pump Displayed only if a Viessmann solar control module (SM1) is
installed. The value can be reset to “0” with “
D ”
0 0 0 5 0 6 h
7
Hours run, output 22 Displayed only if a Viessmann solar control module (SM1) is
installed. The value can be reset to “0” with “
D ”
0 0 0 5 0 6
8
Starts output 22 Displayed only if a Viessmann solar control module (SM1) is
installed. The value can be reset to “0” with “
D ”
0 0 2 8 5 0
9
Solar yield in kWh Displayed only if a Viessmann solar control module (SM1) is
installed. The value can be reset to “0” with “
D ”
Example:
On the display, you can see the number “3” and the
current boiler water temperature.
Note: The scan mode terminates automatically after 30 min.
or if you press .
Vitotronic 100, GC1B Operating

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Scanning
Scanning the Service Messages
After a certain number of burner hours run, e.g. 2500 hours.
After a certain length of time,
e.g. 12 months.
When a certain flue gas temperature is reached,
e.g. 302°F (150°C).
If your heating system is due for a service, the symbol
flashes on the display, and the following displays appear.
Your heating contractor can select when a service should
be carried out:
Notify your heating contractor and acknowledge the
service message by pressing OK.
Note: If the service can only be carried out at a later date,
the service message will reappear after 7 days.
Calling Up an Acknowledged Service Message
Press OK for approx. 4 sec.
Vitotronic 100, GC1B Operating

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Scanning Fault Messages
Scanning
Example:
Fault code shown: “50.”
If any faults have occurred in your heating system, the
symbol
 flashes on the display and the fault code is
shown. The red fault indicator also flashes (see page 7).
1. Notify your heating contractor of the fault code. This
enables the heating contractor to be better prepared
for the service call and may save additional travelling
costs.
2. Acknowledge the fault message with OK.
The symbol
 no longer flashes.
Note:
If you have connected signalling equipment (e.g.
a buzzer) for fault messages, this is deactivated
when the fault message is acknowledged.
If the fault can only be fixed at a later date, the
fault message will reappear the following day.
Calling Up an Acknowledged Fault Message
Press OK for approx. 4 sec.
Note: If there are several fault messages, you can scan
these in sequence by pressing .
Switch the emissions test switch (see page 8) to S .
The display will then show the following:
Emissions Test Mode
Emissions test mode for testing flue gas with boiler water
temperature raised briefly. This test mode should only
be activated by your flue gas inspector during the annual
inspection.
The following functions are activated:
The burner is switched on (the display shows symbol A ).
Note: Burner start-up can be delayed, e.g. through fuel
oil preheating.
Pumps are started.
The adjustable high limit regulates the boiler water
temperature.
Ending Emissions Test Mode
Set the emissions test switch to
a .
or
Close the cover (see page 6).
Vitotronic 100, GC1B Operating

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Rooms Are Too Cold
Cause Remedy
The heating system is off. - Switch the ON/OFF switch ON (see page 8).
- Switch ON the mains isolator, if installed (outside the boiler room).
- Reset the fuse/MCB in the power distribution board (main domestic
fuse/ MCB).
Control unit is incorrectly adjusted. Check settings and correct if required:
-“
w “ must be selected (see page 9).
- Set boiler water temperature (see page 9).
Only when operating with DHW heating:
DHW priority is enabled (“p w “ is displayed).
Wait until the DHW tank has been heated up.
No fuel. For LPG/oil:
Check the fuel reserves and re-order if required.
For natural gas:
Open the gas shut-off valve. If necessary, check with your gas supply
utility.
The
 symbol is shown on the display. Scan the type of fault, make a note of the fault code and acknowledge
the message (see page 14).
If necessary, notify your heating contractor.
Burner start faulty.
The
 symbol is displayed and the red fault
indicator on the burner is illuminated.
Press the reset button on the burner hood or on the boiler front panel.
If there is no reset button, switch the ON/OFF switch (see page 8) first
OFF and then ON again.
Contact your heating contractor if the burner still fails to start.
Vitoair draught stabilizer faulty. Contact your heating contractor.
Press the rotary selector on the motor and rotate it past this position
Aas far as it will go.
Troubleshooting
Rooms Are Too Hot
Cause Remedy
Control unit is incorrectly adjusted. Check settings and correct if required:
- Set boiler water temperature (see page 9).
The
 symbol is shown on the display. Scan the type of fault, make a note of the fault code and acknowledge
the message (see page 14).
If necessary, notify your heating contractor.
Emissions test switch is set to
S .Close the cover (see page 6).
Vitotronic 100, GC1B Operating

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Troubleshooting
There is no Hot Water
Cause Remedy
The heating system is off. - Switch the ON/OFF switch ON (see page 8).
- Switch ON the mains isolator, if installed (outside the boiler room).
- Reset the fuse/MCB in the power distribution board (main domestic fuse/ MCB).
Control unit is incorrectly adjusted. Check settings and correct if required:
- DHW heating must be enabled (see page 10).
- Set DHW temperature (see page 10).
No fuel.. For LPG/oil:
Check the fuel reserves and re-order if required.
For natural gas:
Open the gas shut-off valve.
If necessary, check with your gas supply utility.
The
 symbol is shown on the
display.
Scan the type of fault, make a note of the fault code and acknowledge the
message (see page 14).
If necessary, notify your heating contractor.
The DHW is Too Hot
Cause Remedy
The control unit is incorrectly
adjusted.
Check DHW temperature and correct if required (see page 10).
DHW heating is carried out by the
solar thermal system.
Check settings and correct, if required, at the solar control unit.
Separate operating instructions
Emissions test switch is set to
S .Close the cover (see page 6).
“  ” Flashes on the Display
Cause Remedy
Heating system fault. Scan the type of fault, make a note of the fault code and
acknowledge the message (see page 14).
If necessary, notify your heating contractor.
“”Flashes on the Display
Cause Remedy
The time for a service, as specified by your heating
contractor, has arrived.
Notify your heating contractor and acknowledge the service
message with OK (see page 13).
Vitotronic 100, GC1B Operating

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Maintenance
Maintenance
Safety Valve (DHW tank)
The safety valve function should be checked every six
months by venting, either by the system user or the local
heating contractor. The valve seat may become
contaminated (see the valve manufacturer’s instructions).
Potable Water Filter (if installed)
To maintain high hygienic standards, proceed as follows:
Replace filter element on non-back flushing filters every
six months (visual inspection every two months).
On back flushing filters, back flush every two months.
Damaged Connecting Cables
If connecting cables of the appliance or externally installed
electrical accessories are damaged, replace them with
special connecting cables. Replace only with Viessmann
cables. Contact your heating contractor.
Cleaning
All equipment can be cleaned with a commercially
available domestic cleaning agent (non-scouring).
Clean the surface of the programming unit with the
microfiber cloth provided.
Inspection and Maintenance
Regular maintenance ensures trouble free, energy
efficient, environmentally responsible and safe heating.
Your heating system must be serviced by an authorised
contractor at least every 2 years. For this, we advise you
to arrange an inspection and maintenance contract with
your local heating contractor.
Boiler
Increasing boiler contamination raises the flue gas
temperature and thereby increases energy losses.
For that reason, all boilers should be cleaned annually.
DHW tank (if installed)
Maintenance and cleaning should be carried out no later
than two years after commissioning and thereafter as
required.
Only a qualified heating contractor should clean the inside
of a DHW tank and the DHW connections.
Refill any water treatment equipment (e.g. a water softener
or injection system) in good time, if such equipment is
installed in the cold water supply of the DHW tank.
Observe the manufacturer’s instructions.
Additionally for a Vitocell 100:
We recommend that the correct function of the sacrificial
anode is checked annually by your heating contractor.
The anode function can be checked without interrupting
the system operation.
The heating contractor will check the ground current with
an anode tester.
Vitotronic 100, GC1B Operating

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Vitotronic 100, GC1B Operating
Terminology
Terminology
Open Flue Operation
The combustion air is drawn from the room where the
boiler is installed.
Balanced Flue Operation
The combustion air is drawn from outside the building.
Safety Valve
A safety device that must be installed by your heating
contractor in the cold water pipe. The safety valve opens
automatically to prevent excess pressure in the DHW
tank.
Set Temperature
Default temperature that should be reached;
e.g. set DHW temperature.
Summer Mode
Heating program “ w “.
At warmer times of the year, i.e. when the rooms do not
have to be heated, you can stop heating mode. The boiler
remains operational for DHW heating.
DHW Pump
Circulation pump for heating the DHW in the DHW tank.
Drinking Water Filter
A device that removes solids from the water. The drinking
water filter is installed in the cold water pipe upstream of
the DHW tank or the instantaneous water heater.
Constant Temperature Operation
In constant temperature operation, the heating water
is constantly heated to the selected boiler water
temperature.
Heating Program
With the heating program you determine whether you
heat your rooms and DHW, or only heat DHW, or whether
you shut down your heating system with frost protection
monitoring.
You can select the following heating programs:
“ w “
The rooms are heated and DHW is provided
(winter mode).
“ w “
DHW is provided but there is no central heating
(summer mode).
“9“
Frost protection for the boiler and DHW tank is active,
no central heating, no DHW heating (standby mode).
Note: A heating program for central heating without DHW
heating is not available. If rooms are to be heated,
hot water is generally also required (winter mode).
If you just want central heating, select the “ w “
heating program and set the DHW temperature
to 50°F (10°C) (see page 10). This means that
you will not heat DHW unnecessarily, but frost
protection of the DHW tank is ensured.
Heating Circuit
A heating circuit is a sealed circuit between the boiler
and radiators, in which the heating water circulates.
Heating Circuit Pump
Circulation pump for the circulation of the heating
water in the heating circuit.
Actual Temperature
Current temperature at the time of the scan;
e.g. actual DHW temperature.
Boiler Water Temperature
See “Constant temperature operation”.

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5693 971 - 03
Vitotronic 100, GC1B Operating

Vitotronic 100, GC1B Operating
5693 971 - 03 Technical information subject to change without notice. Printed on environmentally friendly
(recycled and recyclable) paper.