Dantherm Vent R2 User manual

Vent R/C 2/4/6
User’s guide
EN
No. 971762 • rev. 2.2 • 18.09.2015

Der tages forbehold for trykfejl og ændringer
Dantherm can accept no responsibility for possible errors and changes
Irrtümer und Änderungen vorbehalten
Dantherm n’assume aucune responsabilité pour erreurs et modifications éventuelles

Table of contents:
1. GENERAL. ...................................................................................................................................2
1.1 Control circuit board STXC2..................................................................................................2
1.1.1 Function switch................................................................................................................2
1.2 MMI STCU.............................................................................................................................3
1.3 MMI STCU description..........................................................................................................4
1.4 Flow chart (option).................................................................................................................6
1.5 Communication module STIO (option)..................................................................................7
2. USER’S GUIDE............................................................................................................................8
2.1 Main menu..............................................................................................................................8
2.2 Display set-up.........................................................................................................................9
2.2.1 Language selection...........................................................................................................9
2.2.2 Adjusting the display contrast..........................................................................................9
2.3 Time setting..........................................................................................................................10
2.4 Filter configuration...............................................................................................................11
2.5 Setting of manual running mode...........................................................................................13
2.6 Setting a week program. .......................................................................................................14
2.6.1 Example of setting a week program...............................................................................15
2.7 Alarms...................................................................................................................................17
2.7.1 Critical failure reset........................................................................................................19
2.8 Reading the actual conditions...............................................................................................21
2.9 Reading technical data..........................................................................................................21
3. CONTROL STRATEGY. ...........................................................................................................26
3.1 Ventilation. ...........................................................................................................................26
3.1.1 Fresh air reduction at low outside temperatures. ...........................................................26
3.1.2 Filter surveillance...........................................................................................................26
3.2 Temperature control..............................................................................................................26
3.2.1 Heat recovery. ................................................................................................................27
3.2.2 Reheater coil. .................................................................................................................27
3.2.3 Cooling at summer nights..............................................................................................27
3.3 Clean blowing function - heat wheel....................................................................................29
3.4 De-icing function..................................................................................................................29
3.5 Fan override..........................................................................................................................29
3.5.1 HUMIDITY OVERRIDE .....................................................................................................29
3.6 Displacement of temperature set point. ................................................................................29
3.7 Extended operation...............................................................................................................29

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1. General.
The control system is based on the following control units:
A STXC2 control circuit board that is mounted in the ventilation unit.
A STPT circuit board with a two-channel pressure sensor. It is mounted in the ventilation unit.
A STCU wall mounted MMI (Man Machine Interface).
A STLD wall mounted flow chart with LED’s (option).
A STIO circuit board for connection to a BMS (Building Management System) (option).
A single wire system (serial) communication) connects the circuit boards.
1.1 Control circuit board STXC2.
The STXC2 control circuit board and the two-channel pressure circuit board STPT2 give complete
control of air temperature and air volume by measuring and regulating the incoming signals (data).
The control of the air volume set point is displayed in m³/h, and keeps the air volume constant
independent of the duct pressures.
Regulating the amount of energy recovery by speed control of the heat wheel or, controlling the by-
pass damper in an air-to-air plate heat exchanger controls the temperature.
The active part of the temperature control is based on a plug connection on the ventilation unit. The
plug gives the possibility of connecting an external electric or water (LPHW) heating coil.
The ventilation system can also control a Chilled water or DX cooling coil.
There is the option of pre-cooling at night in the summer periods and reduction of ambient air
introduction in extreme cold winter periods.
1.1.1 Function switch.
The ventilation unit is equipped with a function switch that has the positions AUTO, OFF and
MAN (Manual).
AUTO OFF MAN

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If the serial connection to the MMI is not present and the function switch is in position MAN, the
ventilation unit is controlled by the following factory settings on the control circuit board STXC2:
Humidity set point: 60%.
Ambient air volume: 100% (with mixing section).
Fan set point: Maximum air volume.
Temperature set point: 20°C (room temperature control).
The MMI is connected and the function switch is in position MAN, the ventilation unit is controlled
by the manual settings. See chapter 2.5 Setting of manual running mode.
The ventilation unit is controlled in a priority, that defines the operational mode:
1: The function switch on the ventilation unit has the highest priority.
2: Then the communication module STIO controls the operation. See chapter 1.5 Communication
module STIO. The function switch on the ventilation unit is in position AUTO.
3: The MMI STCU controls the operation. See chapter 1.3 MMI STCU description.
By activating the push button Manual the ventilation unit is controlled by the manual settings.
By activating the push button Auto the ventilation unit is controlled by the week program.
The function switch on the ventilation unit is in position AUTO.
1.2 MMI STCU.
The separate STCU MMI is equipped with an alphanumeric display and push buttons, and can be
placed on a wall up to 50m away from the ventilation unit. The wiring must not be fitted outside the
building. The ventilation unit is simple to operate with the MMI and it is with this that the settings
for the running conditions are entered.
The primary settings for the running conditions are entered in a week program.
A six-wire plug connection connects the control circuit board STXC2 to the MMI.
If the function switch on the ventilation unit is in position AUTO the ventilation unit will not run
without the MMI or the communication module STIO connected (See chapter 1.5 Communication
module STIO (Option)).
If the serial connection to the MMI is not present and the function switch is in position MAN, the
ventilation unit is controlled by the following factory settings on the control circuit board STXC2
(See chapter 1.1.1 Function switch).

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1.3 MMI STCU description.
The MMI STCU unit is delivered in a separate cabinet ready for DIN-rail mounting on a wall. The
display texts on the MMI STCU can be selected in Danish, English or Swedish.
The MMI STCU is equipped with an alphanumeric display, a three-coloured indication LED and
eight push buttons.
Indication LED
Menu UP
Decrease value
Increase value
Menu DOWN
Manual run
Auto run
Stop unit
Menu select / Save
The three-coloured indication LED provides information quickly about the running condition:
Green: The ventilation unit is OK.
Yellow: The ventilation unit needs inspection but runs (blocked filter).
Red: The ventilation unit is stopped due to a critical failure.
The indication LED shifts from green to yellow or red if a failure occurs on the ventilation unit. The
relevant alarm text is shown on the display (See chapter 2.7 Alarms).

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The three push buttons Manual, 0and Auto are used to select the running mode of the ventilation
unit. The lowest line on the display indicates the actual running mode with the symbol , which
points to one of the three push buttons.
By activating Manual the ventilation unit is switched to run in manual mode, that is user defined
(See chapter 2.5 Setting of manual running mode). The ventilation unit will now run according to
the manual settings for the next 2 hours (factory setting 2 hours - maximum 24 hours) and, once this
time has elapsed it will return back to the settings in the week program.
This function is very useful if, for example, you want to start or stop the ventilation unit in
unoccupied periods, without making changes in the week program.
By activating 0the ventilation unit stops until Auto or Manual gets activated. This function can be
useful if you want to stop the ventilation unit on short working days.
By activating Auto the ventilation unit follows a pre-defined week program, which is user defined
(See chapter 2.6 Setting a week program).
The following push buttons are used to select menu and change/save settings on the display.
By pressing or it is possible to pick a specified menu line. The highlighted menu line shows
the actual sub menu.
When you want to select a sub menu you have to press Enter.
To increase or decrease a set point value push the buttons +or –. Press Enter to save the corrected
set point.
Moving to a menu that is above the actual menu press until the required menu appears.

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1.4 Flow chart (option).
A flow chart equipped with LED’s can be connected to the MMI. The flow chart indicates the actual
condition for security thermostats, fans, filters etc.
The flow chart gives an easy to read and a clear view of run and fault conditions in the ventilation
unit.

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1.5 Communication module STIO (option).
Connection of the communication module STIO via the serial communication line it enables the
operation and monitoring by the BMS. The function switch on the ventilation unit is in position
AUTO when using the communication module.
By activating the analogue and digital inputs of the STIO the control will more or less be taken from
the MMI STCU.
The analogue inputs are connected to 2-10VDC signals and the digital outputs are activated by
24Vac or 12VDC supply. Some of the analogue inputs have predefined functions as set points and
running conditions.
Every single input has it’s own enable input, that activates the specific function. Functions that not
are selected on the STIO will automatically be controlled by the MMI STCU.
The analogue and digital outputs makes external monitoring possible.

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2. User’s guide.
2.1 Main menu.
When there has been no activity for a few minutes the display will show the following primary
menu:
The actual room temperature, supply air volume and the running program step are shown on the
display.
If the ventilation unit is equipped with damper motors (ON/OFF or modulated 0-10V) on the fresh
air duct and exhaust air duct or a humidity sensor, the status for these is also shown on the display.
By pressing Enter the display shifts to the main menu. The backlight on the display is turned on. If
no push button has been activated within 2 minutes, the STCU automatically turns back to the
primary menu and the back light is turned off.
The push buttons and shift between the sub menus.
Main menu Monday 12:21
Adjustm. / clock
Ventilation / climate
Alarms
Technical data
Actual room temp C +20,7
Supply m3h 02500
Monday 12:21
Actual prog no 01

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2.2 Display set-up.
2.2.1 Language selection.
From the main menu the sub menu Technical data is selected. The sub menu Language appears:
Selecting a language with the push buttons and . Then press Enter and the language is selected.
2.2.2 Adjusting the display contrast.
From the main menu the sub menu Technical data is selected. The sub menu Processor appears:
By pressing the push buttons -and +it is possible to adjust the display contrast. Then press Enter
and the selected display contrast is saved.
Technical data
Language
English
Danish
Swedish
Main menu Monday 12:21
Run time 00023
Comm error % 034
STCU CpuVer 017
STXC CpuVer 015
STPT CpuVer 011
STHP CpuVer
STIO CpuVer
Mode 9
Main menu Monday 12:21
Technical data
Processor
Com Retry 00726

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2.3 Time setting.
From the main menu the sub menu Adjustm. / clock is selected. Select the sub menu Clock adjust:
By pressing the push buttons and the actual data for weekday, time, date, month and year are
selected. The settings are changed by the push buttons +and –. Press Enter after inputting the
settings and the changes are saved.
Adjustm. / clock
Clock adjust
Day Monday
Time 13:31
Date 29
Month 06
Year 00
Main menu Monday 12:21

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2.4 Filter configuration.
It is necessary to run the filter test program at a specific air volume (”filter check value”) to enable
& set the filter failure (dirty filter) alarm. It is only possible to get an alarm at the specific air
volume. The filter test is made by the following procedure:
1. The ventilation unit is turned off. The function switch is in position OFF.
2. The push button 0is activated on the MMI STCU.
3. Choose a maximum air volume [m³/h].
Choose an acceptable differential pressure loss for the filter(difference between clean and
dirty filter).
Dantherm Air Handling recommends a differential pressure loss of 60 Pa.
The function switch on the ventilation unit is now turned to position AUTO.
In the following example a ”filter check value” at 2500m3h is used. This is the air volume
setting used in the week program (See chapter 2.6 Setting a week program).
Use the push button to select the data point Start filtertest and press ENTER.
The control system accelerates the fan motors up to the selected ”filter check value”.
350 seconds after the fan motors are accelerated up to their maximum speed they run for
further 50 seconds. Data for the ventilation unit is set.
The time left for the filter test is show on the display.
Filter configuration
Check at m3h 02500
Accepted d/Pa 0060
Start filtertest ENTER
Technical data
Main menu Monday 12:21
Filter configuration
Check at m3h 02500
Accepted d/Pa 0060
Start filtertest ENTER
Technical data
Main menu Monday 12:21
Measuring wait sec. 400

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With 48 seconds remaining the control system gives a feedback about the filter test.
If the selected ”filter check value” is near the maximum air volume that the ventilation unit
can handle, the filter test will fail.
If a lower air volume is accepted in the week program, the filter test can be made
another time with a lower ”filter check value”.
But if a lower air volume isn’t accepted in the week program, the ventilation unit can’t
run with automatic filter surveillance.
In the configuration menu the function automatic filter surveillance (menu point ”Auto
filter surv.”) is then going to be disabled. See service engineer’s guide for further
information.
After 400 seconds (approximately 7 minutes) the ventilation unit is ready for use.
Filter configuration
Check at m3h 02500
Accepted d/Pa 0060
Start filtertest ENTER
Technical data
Main menu Monday 12:21
Measuring wait sec. 048
Filter test Ok
Filter configuration
Check at m3h 02500
Accepted d/Pa 0060
Start filtertest ENTER
Technical data
Main menu Monday 12:21
Measuring wait sec. 048
Filter test failed

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2.5 Setting of manual running mode.
From the main menu the sub menu Adjustm. / clock is selected. Select the sub menu Manual
override. After pressing Manual the ventilation unit will run with the following data:
Temperature, air volume and manual-time are displayed. Settings are adjusted by pressing the push
buttons +and –.
Select the data point Manual hours for setting the running time (setting in whole hours from 1 to 24
hours) in manual. After this time has elapsed the ventilation unit reverts to the settings in the week
program.
After inputting the settings press Enter to save.
Temp set point C 20
Ventilation m3h 02500
Manual hours 02
Manual override
Main menu Monday 12:21
Adjustm. / clock

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2.6 Setting a week program.
From the main menu the sub menu Adjustm. / clock is selected. Select the sub menu Program step:
Pick a specific data point with the push buttons and .
In the data point Program step no the program step is selected (maximum 20 steps), which is going
to be changed.
Individual days can be selected such as Monday, Tuesday, Wednesday etc., workdays can be
selected (Monday to Friday), weekends can be selected (Saturday and Sunday) and a full week
(Sunday to Monday).
Time (24 hour clock), temperature and air volume are selected by the push buttons +and –.
After inputting the settings in a program step press Enter to save. The next program step can be
selected in the data point Program step no.
In any unused program steps up to 20, the data point Time has the setting --: --. The control system
will then jump to the next program step.
The data point setting Time has the default factory setting --: --.
Setting for mixing section
If the ventilation unit is equipped with damper motors in a mixing section, fresh air setting can be
chosen from 0 (closed) to 100 (fully open).
Adjustm / clock
Program step
Program step no 01
Ventilation m3h 02500
Day(s) Monday
Time 08:00
Temp set point C 20
Night cooling No
Main menu Monday 12:21

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2.6.1 Example of setting a week program.
The following shows an example of a week program including cooling at summer nights (See
chapter 3.2.3 Cooling at summer nights). For further information see chapter 2.6 Setting a week
program.
Program step no. 01 and 02:
The week program begins by turning the ventilation unit on, on workdays at 08.00 and ventilation
unit is turned off at 16.00.
The room/return temperature set point is 20C.
Program step no. 03:
The ventilation unit runs providing free cooling on summer nights on workdays, early in the
morning from 04.00.
Free cooling on summer nights:
The most suitable period to use the function free cooling on summer nights is at night or early
in the morning. A quick cooling of the room is achieved.
Program step no. 04:
The ventilation unit is turned off at the weekend.
Program step no.: 01.
Program step no.: 02.
The room/return temperature has a default factory setting of 20  C. When the ventilation unit is
turned off, the room will not be supplied with heating.
Adjustm / clock
Program step
Program step no 01
Ventilation m3h 02500
Day(s) Workd.
Time 08:00
Temp set point C 20
Night cooling No
Main menu Monday 12:21
Adjustm / clock
Program step
Program step no 02
Ventilation m3h OFF
Day(s) Workd.
Time 16:00
Temp set point C 20
Night cooling No
Main menu Monday 12:25

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Program step no.: 03.
Program step no.: 04.
Adjustm / clock
Program step
Program step no 03
Ventilation m3h OFF
Day(s) Workd.
Time 04:00
Temp set point C 20
Night cooling Yes
Main menu Monday 12:28
Adjustm / clock
Program step
Program step no 04
Ventilation m3h OFF
Day(s) Weekend
Time 00:01
Temp set point C 20
Night cooling No
Main menu Monday 12:35

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2.7 Alarms.
If the ventilation unit does not work properly, an alarm is shown on the display and the indication
LED shifts colour from green to yellow or red.
The indication LED lights yellow as a warning. A non-critical failure has appeared. The ventilation
unit does not stop, but only needs inspection:
-”Filter exhaust”
-”Filter supply”
The indication LED shifts to red. A critical failure has appeared. The ventilation unit is stopped (not
Heat wheel):
-”Fail preheat”
-”Fail reheat”
-”Fire supply”
-”Fire exhaust”
-”Fan supply”
-”Fan exhaust”
-”Flow supply”
-”Flow exhaust”
-”Supply sensor”
-”Return sensor”
-”Ambient sensor”
-”Preheat sensor”
-”Heat wheel”
A critical failure must be manually reset so that the ventilation unit can be re-started.
If the connection to the STXC2 control circuit board is not present, the following communication
failure appears on the display:
- ”No STXC Detected”
Actual room temp C +20,7
Supply m3h 02500
Monday 12:21
Actual prog no 01
Alarm
Fail preheat

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The indication LED is in this case switched off.
To get information about the alarms select the menu Alarms in the main menu:
Two sub menus gives information about the actual alarms and alarms listed in a “alarm history” that
have occurred since the last power failure:
Actual alarms:
Alarms since
last power failure:
Alarms listed in the “alarm history” disappear at power failure or if the connection between the
control circuit board STXC2 and the MMI STCU has been disconnected.
Adjustm. / clock
Ventilation / climate
Alarms
Technical data
Alarms
Actual
History
Main menu Monday 12:21
Actual
No failures
Main menu Monday 12:21
Alarms
History
Power failure
15:34 02-10-00
Main menu Monday 12:21
Alarms