Smart temp SMT-400 Instruction Manual

User & Installer Manual
SMT-400 "Enterprise"
Wi-Fi Thermostat
Ver 1.0
Jan 2018

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SMT-400 Draft Manual
Great care has been taken in the preparation of this manual. Smart Temp Australia P/L takes no responsibility for errors or omissions contained in this
document. It is the responsibility of the user to ensure this thermostat, or the equipment connected to it is operating to their respective specifications
and in a safe manner.
Due to ongoing product improvement, Smart Temp Australia P/L reserves the right to change the specifications of the SMT-400 thermostat (or its
components) without notice.
All rights reserved. © Smart Temp Australia P/L 2018
Intellectual rights apply.
Manual Version History
January 2018 Initial Release
First release of the SMT-400 Manual

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Contents
Contents .......................................................................................................................................3
User Manual .................................................................................................................................4
Introduction.........................................................................................................................................4
The Touch Screen - Explained..............................................................................................................4
Making Comfort Adjustments .............................................................................................................6
Turning your SMT-400 ON or OFF.......................................................................................................6
Adjusting your Set points ....................................................................................................................6
Adjusting your Fan mode & Speed......................................................................................................6
Programming.......................................................................................................................................7
Using the Smart Temp “Comfort” App ................................................................................................7
Installation..................................................................................................................................10
Mounting the SMT-400 Thermostat..................................................................................................10
Setting the hardware switches..........................................................................................................10
Typical Drawings .........................................................................................................................11
Using Remote Temperature Sensors ...........................................................................................14
Attaching the Thermostat ...........................................................................................................14
Advanced Installer Settings.........................................................................................................15
Control Logic .....................................................................................................................................24
Commissioning............................................................................................................................24
Advanced Functions ....................................................................................................................25
Universal Input Functions .................................................................................................................25
0-10V Output Functions....................................................................................................................26
Assignable Relay Functions ...............................................................................................................26
ModBus Communications .................................................................................................................27
Outside air economy cycle ................................................................................................................27
High and Low Balance Points ............................................................................................................28
High Balance Point ............................................................................................................................28
Low Balance Point .............................................................................................................................28
Setting Up the Heat & Cool Off Functions.........................................................................................28
Belimo ™ 6 Way Valve R30… #....#... B2 Series.................................................................................28
Supply Air Temperature Monitoring .................................................................................................28
Occupancy Detection Logic ...............................................................................................................28
Specifications..............................................................................................................................30
Sensor Reference Table .....................................................................................................................30
Troubleshooting..........................................................................................................................31

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User Manual
Introduction
Congratulations for your purchase of the Smart Temp SMT-400 thermostat. Please take time to read and understand
these simple instructions so that you may gain maximum benefit from this intuitive and powerful air conditioning control
thermostat.
A simple to use touch screen interface is provided that will offer you clear feedback of the comfort of your home or office
and the status of your heating and air conditioning system.
The SMT-400 can be used a simple manual thermostat however when connected to your Wi-Fi network numerous extra
functions are available. Please see the section “The app Explained on page 7 of this manual.
Please Note:
The SMT-400 thermostat can be configured by your installer to a large variety of configurations, each with specific
functions so that your SMT-400 thermostat is perfect for you and your individual needs. As such, this manual may
describe a function or feature not active on your thermostat.
The Touch Screen - Explained
Buttons
A number of "buttons" or touch arears are available on the SMT-400 touchscreen, these buttons are used to adjust the
heat and cool set temperature, select the Heating or Cooling Mode or to adjust the Fan Speed and function.
Current Room Temperature
This is the temperature your SMT-400 is measuring either with the sensor fitted directly to the SMT-400 or any remote
temperature sensors wired into the SMT-400 remote temperature sensor terminals. This is the temperature your SMT-
400 will use as room temperature.
Room Humidity
This indicates the current level or relative humidity within the room. The SMT-400 can simply display this value or, if set
be the installer, take some action to increase or decrease room humidity.
Heat (or Cool) Set Temperature
This part of the display shows the Heat (or cool) setpoint. If the word heat and the heat (or Cool) set temperature is
shown your SMT-400 "Enterprise" is ready to heat (or cool) should the room temperature require it. If the word Heat
(or Cool) in this part of the LCD is blinking, then there is a safety delay preventing the heating (or Cooling) from running.
This delay is up to a maximum of 4 minutes.
Heat (or Cool) Set Point Adjustment
Use the up or down buttons to adjust your Heat (or Cool) set point.

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Outside Air Temperature
This is the current outside air temperature measured either from the hard-wired outside air sensor of from the internet
for your location (if Wi-Fi is active on your SMT-400).
Door / Window Open
The SMT-400 has advanced energy saving functions such as door or window monitoring. (Optional door window switch
required). If enabled by the installer, when a door or window is left open for longer than a few minutes the SMT-400 will
display this text and may restrict user functions until the door or window is closed.
Un-Occupied Mode Indicator
The SMT-400 can determine whether the room is occupied or unoccupied and alter the set points accordingly. When the
room is un-occupied this text is shown to inform you thermostat functions are locked.
Set Point Limit Reached
Pre-defined installer set point limits prohibit the user from apply heating set points that are too hot or cooling set points
being too Cool. When the installer defined set point limit is reached the SMT-400 will chirp its beeper and flash the set
point limit text on the display to indicate no further adjustment is permitted.
Function Locked
This Icon will be shown whenever you try and access a function or press a button that is locked out.
Fault
When this text is shown your SMT-400 has been provided with information from your air conditioner or building
management system that a fault in the system has been detected. This may affect the function of the SMT-400
thermostat.
The text “Fault” may be shown if your SMT-400 can connect to your wireless Wi-Fi network router however your router
has lost internet access and therefore the SMT-400 cannot connect to the Smart Temp Comfort App server.
(Note, the text "Fault" on the SMT-400 DOES NOT indicate a fault with the SMT-400 itself)
Fresh Air in Use
Your SMT-400 can measure the outside air temperature and if cool enough draw in outside air to cool your home or
office. When outside air is being used this text is displayed.
Communication Icon
This ICON is show whenever the SMT-400 is communicating via Wi-Fi. It is shown to indicate that your SMT-400 may be
receiving control information from a location other than the SMT-400 buttons. This may include set point changes,
modes or other settings that effect your comfort levels. The Icon is not shown if communications are disabled or not in
use. It will flash if there is a communications error or during Wi-Fi setup.
(Note –ModBus communications in progress is indicated by the decimal point in the room temperature flashing.
Mode Adjustment
Tapping this button will cycle the SMT-400 through all available modes, heating, cooling, or Auto mode. These functions
are described in more below.
Fan Mode Adjustment
Pressing & Holding this button will cycle the SMT-400 through all available Fan Modes being Auto Fan or Fan On mode.
These functions are described in more detail below.
Fan Speed Adjustment
Tapping this button will cycle the SMT-400 through all available Fan Modes being Low speed, medium speed, high speed
or Auto fan speed where the SMT-400 will select the most appropriate fan speed for the current conditions. These
functions are described in more detail below.

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Making Comfort Adjustments
Turning your SMT-400 ON or OFF
The mode button in the lower left of the SMT-400 changes the thermostat mode. Each tap of this button cycles the SMT-
400 through all available modes. (note, not all modes may be permitted on your SMT-400 thermostat)
OFF
When off is displayed your SMT-400 will not request your heating or cooling system to run. There is no active control of
the room temperature.
Your SMT-400 may have been configured by your installer, or via the Smart Temp Comfort App to automatically shut
down if connection to the Smart Temp server is lost for more than 1 hour. (to prevent wasted energy that may occur due
to your inability to remotely turn your SMT-400 off).
If the SMT-400 has been shut down via this method the Text “Off” will flash. If you are at the SMT-400 you can simply
touch the mode button to restart your heating and cooling once again.
Note your SMT-400 will now continue to run until you manually select a new mode or setpoint at the thermostat or by
the Smart Temp Comfort app once the server connection is restored.
Heat
Your SMT-400 will request your heating system to run once your room falls below your preferred heat set temperature.
When Heat is shown steady your SMT-400 is ready to call for heating if needed. When Heat is flashing your SMT-400 has
asked your heating system to run.
E.Heat
Your SMT-400 will request your Emergency heating system to automatically run once your room falls below your
preferred heat set temperature or you additionally may be permitted to select E.Heat mode manually in some cases.
When E.Heat is shown steady your SMT-400 is ready to call for emergency heating if needed. When E.Heat is flashing
your SMT-400 has asked your emergency heating system to run.
Cool
Your SMT-400 will request your cooling system to run once your room raises above your preferred cool set temperature.
When Cool is shown steady your SMT-400 is ready to call for cooling if needed. When Cool is flashing your SMT-400 has
asked your Cooling system to run.
Auto
Your SMT-400 will request your Heating or Cooling system to run once your room temperature is warmer or cooler then
you desire. When Heat or Cool is flashing your SMT-400 has asked your Heating or Cooling system to run.
Adjusting your Set points
Depending on the Mode selected as described above, the SMT-400 will show either the heat, cool or both the heat and
cool set points and set point adjustment arrows. Tapping the Up or Down button will increase or decrease the set
temperature by 0.5c (or 1 F) per tap. If you press and hold the up or down button for the heat or cool set point the
desired temperature will move rapidly. The range of adjustment is from 5 to 50C (41 to 122F. NOTE, when in deg F mode,
in the extremely unlikely event you wish to have a set point above 99F, the set Temperature display will change to show
2 large digits with a small “1” behind it. Such as 221to indicate 122F).
Please note:
The SMT-400 will not permit the heating set point to be set to a higher temperature than the cooling set point.
Should you attempt to adjust the heating set point above the cooling set point, or adjust the cooling set point below the
heating set point the SMT-400 will “push” the opposing set point away. Your installer will have defined how close the
heating and cooling set points can be.
Adjusting your Fan mode & Speed
The SMT-400 can control systems with a single Fan speed or with 3 Fan speeds. The Fan button behaves different based
on how many fans speeds are being controlled.
Single Speed Fan systems-. Tap this button to cycle between Continuous Fan (Fan ON) and Auto Fan.
Three Speed Fan systems –Tap this button to cycle between the 7 available fan modes being Low speed, Medium
speed, High speed & Auto Fan speeds in Auto fan mode and then Low speed, Medium speed, High speed in Fan ON
mode.

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If the SMT-400 is OFF, tapping the “FAN” button will turn the fan ON or OFF as desired. If your system has 3 fan speeds
these can also be selected by tapping the “FAN” button.
Programming
Although your SMT-400 is not a traditional programmable thermostat it does provide a cloud based scheduling function
via the Smart Temp Comfort App. Using your app, select schedule enter your desired times and temperature settings
into the app.
The Smart Temp Comfort app web server will then send temperature setpoint updates to your SMT-400 “Enterprise”
thermostats at the time scheduled.
The Web Portal additionally permits you to program in holidays that will be used to control your SMT-400 “Enterprise”
thermostat.
Please note the thermostat must be set to the desired mode (Heat Cool Or Auto) for the schedule to work. Setting a
scheduled cool set temperature will have no effect if your SMT-400 thermostat is in Off or Heat Only mode
Using the Smart Temp “Comfort” App
The “App” Explained
The SMT-400 "App" will permit you to control all aspects of the wall thermostat. It will also permit you to perform
many additional functions such as applying a schedule or automatically turning your home comfort system on or off
as you approach or leave your home.
Please refer to your App for up to date information on the functions available.
Pairing your SMT-400 to Your Wi-Fi Network for the First Time
Connecting your SMT-400 to the internet is a very simple process and no more difficult than connecting a lap top
or other Wi-Fi device to your home or office wireless network.
Step 1
Make sure your smart device is paired with the same network that you wish to pair your SMT-400 thermostat with.
Example, your home Wi-Fi network if installing the SMT-400 in your home.
Step 2
Download and install the "Smart Temp Comfort App" as you would any other app for your device if not
previously installed. (Both Apple or Android versions available) and log into or create a new Smart Temp
Comfort App account. Consult your smart device manual for help with downloading and installing apps
if needed. You will need follow the prompts if setting up a new Smart Temp Comfort app account and
respond to confirmation emails that will be sent.
Step 3
In the Smart Temp app main window, click on the “ +” icon in the top right
of the app window to add a new device. –Select the “Smart Wi-Fi” option
in the pop up box that appears.
Step 4
In the Connect Window that opens, ensure the Wi-Fi network you wish to pair your SMT-400
with is shown in the Network box (this will be the same Wi-Fi network your phone is paired
with. Enter the password for the shown network in the Password box. (Note -The app does
not have access to your password data in the smart device, hence your need to enter this
information manually)
Step 5
Power up your SMT-400 Controller. After it displays
the firmware version and performs a display test, the
Thermostat will power up and show a typical display.
The Wi-Fi symbol will flash. Simply touch the flashing
Wi-Fi symbol to begin the pairing process.
(The Wi-Fi symbol will time out after 2 minutes –if this happen simply press
and hold the display where the Wi-Fi symbol would shown for 5 seconds–Just
above the centre of the Mode button)

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Step 6
The SMT-400 will perform a countdown from 10 to 0 as it enables, tests and resets the Wi-Fi radio within the
thermostat. When the thermostat reaches 0 (zero) –press the connect button on the Smart Temp Comfort App. The
app will then search your paired network looking for your SMT-400. Once detected on the network the app will
automatically upload the network ID and password into the SMT-400 memory. If the app fails to find your device,
try the connection process again. If you have repeated failed attempts, you may need to hard reset (reboot) your
smart device.
Step 7
If connection is successful, your SMT-400 will display a 3-digit security code. Enter this
code into the Smart Temp app in the box that has popped up. Press “Enter” to
confirm. If you entered the correct passcode in your app the process is complete and
the Smart Temp Comfort App will return to the device screen showing your SMT-400
thermostat. The Satellite icon will remain on solid confirming your connection to the
building Wi-Fi router. You can now use your app from anywhere in the world that has
Wi-Fi access.
If you enter the incorrect passcode the SMT-400 will flash “Fault”. You will need re-enter your pairing code.
Note
On rare occasions after you pair your device the App may note advance from the connect screen, simply press
“connect again” and re-enter enter the PIN the thermostat displayed.
Adding Extra Devices to Your Account
Once you have your Smart Temp "Comfort App" account setup you are free to add as many SMT-400 (and other
Smart Temp Wi-Fi enabled devices) that you wish to your account. This permits you to control the SMT-400 that is
installed at home, in your office or any other place that you have a Smart Temp Wi-Fi device installed and paired
with the local Wi-Fi network. There are no practical limits on the number of devices you can pair to your account.
Simply open the options window on your app and select "Add Device" and add the device as explained in that devices
manual.
Permitting Others to Control Your SMT-400
Once you have your Smart Temp "Comfort App" account set up and paired with your SMT-400 you can permit others
to also have Wi-Fi control of your SMT-400. For example, a SMT-400 may be installed in a home and can then invite
other family members to join in controlling the same SMT-400 thermostat.
Step 1
Ensure the person you wish to add has a Smart Temp “Comfort App” installed on their smart device and a user
account set up.
Step 2
Touch the Options Window in the Smart Temp "Comfort App" and select "Add User".
Step 3
Enter the account name and privilege level of the user you wish to add and press submit. This person will be sent
a message on their app inviting them to share control of your thermostat. You will be sent a message informing you
that the user has accepted or declined access to your SMT-400.
Please Note: The SMT-400 will respond to the latest command it receives from either direct input at the thermostat or
from any Wi-Fi commands.
Resetting Your App Pairing
If you change home or router you will need to reset your SMT-400 router pairing and set up a new connection with
your new router.
Step 1
If your SMT-400 fails to connect to a router stored in its memory the WiFi symbol will flash. Press the wi-fi symbol
on the SMT-400 display to reset the radio back to factory settings
Step 2
Follow the instructions above in “Pairing you SMT-400 to the network for the First Time”

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Wi-Fi Fault indications
The Satellite symbol will flash if it cannot or is not paired with your Wi-Fi Router.
Please check your Wi-Fi in your building is working and within range of the SMT-400
The satellite symbol will not be show if it has not been able to connect to your router.
If after 2 minutes of power up the SMT-400 has not connected to a wi-fi router it disables the flashing wi-fi
icon on the LCD (some people may not wish to use the SMT-400 Wi-fi function so the icon is disabled). If you
wish to re-pair the SMT-400, simply press the location of the icon on the SMT-400 display for 5 seconds.
The satellite Symbol is Shown steady, however the word “Fault” is also shown on the display.
The Word “fault” can be displayed for many reasons. One reason the text “Fault” may be displayed is because
your wi-fi network cannot connect to the Smart Temp server. This could be a problem with your internet
service provider or an issue with the Smart Temp server. To determine if it is the Smart Temp server issue visit
the server at www.smarttempapp.com

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Installation
Significant effort has been taken to make the SMT-400 thermostat system intuitive, reliable and easy to install. Using a
common-sense approach to the installation will ensure this product is easily installed and to the customer’s satisfaction.
Please read and understand this instruction manual so that installation, testing and commissioning process is undertaken
in an efficient and effective manner.
As with any air conditioning project undertaken, careful installation is the key to a successful outcome. Time taken during
this installation process will be rewarded with a happy customer and fewer call-backs.
The steps required to install the SMT-400 thermostat are:
1. Read and understand this manual.
2. Mount the SMT-400 back plate in a suitable location.
3. Set the 8 DIP switches to match the needs of the project / user.
4. Wire the optional remote temperature sensor(s) or switches if required.
5. Power up the air conditioning system.
6. Set the installer software options (if required).
7. Test the heating, cooling, and other functions –Commissioning.
For convenience, the layout of this manual is in the same order as the steps listed above
Mounting the SMT-400 Thermostat
The SMT-400 can only be as accurate as the on-board temperature sensor or its optional remote temperature sensor(s)
permits. It is therefore essential that the SMT-400 be installed in a location that is typical of the ambient room
temperature. Do not install the thermostat in a draft, near a floor, behind doors or on a non-insulated external wall. Also
avoid placing the thermostat in areas where the air movement is limited, affected by direct sunlight or other areas not
“typical” of the temperature of the room.
Further, when mounting the SMT-400 be aware that drafts may travel down the inside of cavity walls, (especially if
mounted on external walls) and enter the back of the thermostat or sensor enclosure through the cable entry holes in
the wall. It is important to fully seal these holes to prevent any drafts affecting the internally mounted temperature
sensor. It is recommended to mount the SMT-400 or remote sensors between 1.5 and 1.7 metres from the floor where
possible.
Move the control wires through the large opening in the thermostat base plate then place the thermostat base on the
wall and using appropriate screws, firmly attach the thermostat base to the wall. Block any holes where cables enter the
back of the thermostat to prevent drafts entering through these holes affecting the sensor.
Setting the hardware switches
Switch
Off
On
Sw1 –Fan Speeds
1 Speed Fan
3 Speed Fan
Sw2 –Equipment Type
Heat Cool
Heat Pump (O/B
terminals)
Sw3 –Stages
1 Stage
2 Stages
Sw4 –Reversing Valve
If Sw 2= ON –Heat Pump
Energise in cool (O)
Energise in heat (B)
Sw4 –Fan Mode
If Sw 2= OFF –Heat/cool
Fan Control by Heater
(HG)
Fan Control by T’stat (HE)
Sw5 –Anti Cycle Timer
Off
4 Minutes
Sw6–Klixon Mode
Off
On
Sw7 –Heat Pump Mode
Conventional Heat Pump
Fossil Fuel Mode
Sw8 –Commercial mode
Off
On
Typical drawings have been provided on page 11 of this manual that will assist with the selection of the
correct positions for these function switches.
Switch 1 –Relay Assignment
The SMT-400 is fitted with 5 relays capable of switching up to 24VAC @ 1Amp. Switch 1 sets the function of these relays
as either 3 fan speeds with 1 heat and 1 cool operation or single fan speed with 2 heat and 2 cool, in either HP (heat
pump / reverse cycle) or HC (heat with add on cool) mode.
Switch 2 –Equipment Type

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Both heat with add on cool or heat pump types of systems can be controlled by the SMT-400. This switch defines how
the equipment relays operate.
Heat Cool systems use the “W” terminal(s) only for heating and the “Y” terminal(s) only for cooling.
Heat Pump systems use the “Y” terminal(s) for BOTH heating and cooling (the compressor). The “W1” terminal
controls the reversing valve which defines the heating or cooling mode and the W2 is used for Auxiliary heat
or emergency heat as defined in the Installer menu (option 17 on page 18 describes this function).
Switch 3 –Equipment Stages
When it is necessary to control a single stage A/C system fitted with auxiliary heating elements, turn Sw3 OFF thereby
selecting single stage mode. Heating elements controlled by the W2 output are now assigned as stage 2 heat. (Note, if
SW 1 = ON this switch function is internally set as OFF –Single Stage)
Switch 4 –Reversing Valve or Fan Mode
When the SMT-400 is set for Heat Pump mode (Sw2 is on) then this switch sets the reversing valve logic (O/B). When the
SMT-400 is set for Heat Cool mode (Sw2 is off) then this switch sets the mode for the Heater Fan Logic (HG or HE mode).
If SW 2 = OFF then SW 4 Off = Heating Gas. ON Heating Electric.
If SW 2 = ON then SW4 Off= Rev Valve in Cool. On = Rev Valve in Heat.
Switch 5 –Anti Cycle Timer (Compressor Delay)
To protect some A/C systems it is recommended that the compressor does not start within 4 minutes of it switching off.
Note: When power is first applied to the SMT-400 it “assumes” that the compressor has just stopped and applies this anti
cycle delay time before starting.
Switch 6 –Klixon mode
This function uses a mechanical input to set the mode for a 2-pipe system. 2 pipe modes must be defined for one of the
universal inputs in the Installer menu. Installer option 43, 44 or 45 to option 4.
Switch 7 –Heat Pump Mode
The SMT-400 can control both a conventional Heat Pump or a Heat Pump fitted with a Fossil Fuel system. In Australia,
Asia and Europe this type of heat pump is not typically used so it is recommended to leave this switch in the OFF position.
North America customers may need this function depending on the type of Heat Pump under the SMT-400 control.
Switch 8 –Not currently used
Typical Drawings
The SMT-400 has the capacity to control a wide selection
of heating, cooling and air conditioning systems as well as
modulating valves or other devices.
Using the 8 DIP switches (see page 10 and many installer
software options (see page 15), the SMT-400 can provide
many different control methods from its 6 fitted relays
and 3 x 0-10 volt outputs. Examples of only the most
common types of control wiring have been provided
below.
You may need to modify these drawings slightly to specifically suit your individual needs, alternatively contact Smart
Temp at [email protected] or an authorised Smart Temp distributor for installation advice specific to your
application.

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Using Remote Temperature Sensors
If the SMT-400 is installed in a location not suitable for accurate temperature measurement you can connect single (or
multiple) remote room air temperature sensors and wire these sensors to the SMT-400 Auxiliary input terminals. Using
the remote sensor, the SMT-400 can then measure temperature at a distant location from the SMT-400 or measure
temperature over a larger area and control using the average temperature of these multiple locations.
The Smart Temp remote sensors have an internal switch that changes the function of each sensor in “RS-1” mode or “RS-
2” mode. Detail on this switch setting is provided in the manual supplied with the Smart Temp sensors.
RS-1 Sensor Mode –Sensor switch is ON
RS-2 Sensor Mode –Sensor switch is Off.
Please note the configuration of the remote sensors in the examples provided taking note of the switch settings or
inaccurate temperature measurement will result. Other sensor configurations are also available.
Please note you must define the desired universal input for “remote sensing” or “average temperature” measurement.
See installer option 40, 41 & 42 on page 21.
A typical maximum of 40 meters is permitted for sensor runs with 0.3mm or larger shielded cable should be used.
When used in Start/Stop commercial mode (Dip SW8=On), the afterhours run timer can be toggled on or off as required
with a momentary press button on the remote sensor.
As the SMT-400 “auto detects” sensors connected to the Auxiliary input terminals, temperature sensors can also be
switched on and off as required by placing a switch in the sensor wiring to open circuit the sensor loop.
Attaching the Thermostat
Check that the position of the 8 DIP switches matches the requirements of the equipment being controlled and the
specific requirements of the user. Detailed information on the 8 DIP switches can be found on page 10 of this manual.
Check the wiring matches that of the equipment the SMT-400 is to control and that all wiring is tight and not likely to
short between adjacent wires. Equipment wiring information can be found on page 11 of this manual.
If using the ModBus communication capability of the SMT-400, ensure the “A” & “B” data wires are in the correct position
as an error here may affect the communication of the entire network. See page 27 for detailed wiring of the
communications port of the SMT-400.

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Using masking tape or similar, block the hole in the wall where the wiring enters the back of
the thermostat to prevent drafts that may travel down the inside of the wall cavity affecting
the accuracy of the internally fitted temperature and humidity sensor.
When attaching the thermostat to the base, avoid twisting the case as this may stress the
LCD and cause it to crack. Avoid running wiring near the internally fitted sensor.
Take care not to damage or crush the temperature sensor between the two halves of the
case when you close the case. Check this sensor location.
Advanced Installer Settings
The SMT-400 is fitted with many advanced functions that can be finetuned by the installer to specifically match the needs
of the user’s project.
Normally these functions will not need to be altered from the factory default position however, there may be times when
you wish to alter a setting or control capability so that the SMT-400 performance will perfectly match a particular
application. On the next few pages there is detailed explanation of these functions and their range of control.
While in the advanced installer menu, all SMT-400 equipment control functions will be suspended. Normal equipment
operation will continue when you have exited this menu (after any anti cycle delays or safety delays have terminated).
Entering the Installer Menu
To enter the Installer menu, press and hold the centre of the LCD for 15 seconds. After 15 seconds, the LCD will show
“15” (one five).
Adjust this value to “21”–(two one) the factory default PIN (or your previously selected value) by using the up () or
down () button. Tap the centre of the LCD to enter the menu.
If you have entered the correct PIN you will be given the first menu option, if you have entered an incorrect PIN you will
be exited from this menu.
Using the Installer Menu
To move forward through the Installer menu items, tap the arrow
to the lower right. To move backwards through the Installer menu
items, tap the arrow to the lower left.
To adjust the current option, tap the up or down arrows.
To exit the installer menu, press and hold the centre of the LCD for
3 seconds or wait 60 seconds and the menu will be exited
automatically.

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1 Keyboard Lock PIN
This is the required PIN for future entry into the Installer menu. Default is 21.
Range 00 to 99 in 01 steps. To prevent accidental PIN changes, you must press and hold the or buttons for longer
than 1 second to change the PIN value.
(Caution, if you change this value and forget your new PIN, you may need to return the SMT-400 to
place of purchase for unlocking, there may be a fee for this service)
2 Beeper
Controls the beeper that acknowledges each button press.
0 Beeper ON (Default)
1 Beeper OFF.
3 Backlight Brightness in standby mode
Controls the level of the backlight when the buttons are not pressed.
Range 0-20
Default = 10
4 Auto Backlight Brightness
Controls the level of the backlight based on internet dusk setting.
(Note –SMT-400 must be connected to internet and accurate location set)
0 Off (Default)
1 On
5 Backlight Daytime Brightness hours
Controls the level of the backlight based on internet time.
(Note –SMT-400 must be connected to internet and accurate location set)
Range 0-23
Default = 7
6 Backlight Night Time Brightness hours
Controls the level of the backlight based on internet time.
(Note –SMT-400 must be connected to internet and accurate location set)
Range 0-23
Default = 19
7 Buttons Shown
This defines what buttons are shown on the SMT-400 LCD. A hidden button cannot be adjusted
0 All Buttons are shown. (Default)
1 Mode is shown but Fan is hidden
2 Fan is shown but Mode is hidden
3 Mode and Fan and hidden
(Note the temperature setpoint range for Heating and Cooling can be limited in the Heat Limit & Cool Limit menu options
below. Option 11 & 12 below)
Note: If the mode button is hidden, the service and maintenance staff can turn the SMT-400 on or off by pressing and
holding the lower left of the LCD for 15 seconds. 2 chirps indicate the SMT-400 has turned ON. 1 chirp indicates the SMT-
400 has turned off.
8 Permitted Modes
The SMT-400 operational modes can be set to set to suit the demands of the user or the limits of the heating and cooling
system. Selecting the options below defines how the mode button operates
0 Off and Auto (Heat & Cool). (it will NOT display current mode)
1 Off, Auto (Heat & Cool), Heat, Cool. (Default)
2 Off, Heat, Cool.
3 Off, Heat.
4 Off, Cool.
5 Off and Auto only (Heat & Cool). (Will display current mode)

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9 Room and Set Temperature Display
The SMT-400 operational modes can be set to set to suit the demands of the user or the limits of the heating and cooling
system. Selecting the options below defines how the mode button operates
0 Shows both Room and Set Temperature. (Default)
1 Displays the set Temperature only.
(Note, if option 1 is selected, the main temperature display will show the current (or last mode) set point as room
temperature)
10 Temperature Display Format
This option effects all user and installer menu items
Deg C or Deg F as the native temperature format.
0 Displays in Deg C. (Default) (Note, set point adjustment in 0.5C, temperature display in 0.1C)
1 Displays in Deg F. (Note, set point adjustment, and display in 1F)
11 High Range Limit
This value sets the maximum temperature the user can select. The next highest value above this is OFF. When the user
attempts to set a temperature above the “Off Value” the SMT will flash the padlock symbol, Display “Set Point Limit
Reached” text and chirp the beeper twice.
Note - This is NOT the Heat Set Point limit. The heat setpoint limit is option 62 on page 23 of this manual.
Deg C Range is 5C to 45C (Default 30C)
Deg F Range is 41 to 113 (Default 90F)
12 Low Set Temperature Range Limit
This value sets the minimum temperature the user can select. The next lowest value below this is OFF. When the user
attempts to set a temperature below this “Off Value” the SMT will flash the padlock symbol, Display “Set Point Limit
Reached” text and chirp the beeper twice.
Note - This is NOT the Cool Set Point limit. The cool setpoint limit is option 63 on page 23 of this manual.
Deg C Range is 5C to 45C (Default 5C)
Deg F Range is 41 to 113 (Default 41F)
13 Dead band
This sets the difference that must be maintained between the heating and cooling setpoint. If when adjusting a setpoint
it is too close to the other setpoint, the SMT-400 will automatically "push" the other setpoint away to maintain this dead
band value.
Deg C Range is 1C to 5C (Default 1C)
Deg F Range is 1 to 10 (Default 2F)
14 Heat Relay Span
This defines how far from the heating set point the stage 1 heat relay will energise to engage heating. If the SMT-400 is
set for multistage heat control, then stage 2 also uses this value.
Adjustable range Deg C 0.5c to 3c (default is 1c) (in 0.1c increments)
Adjustable range Deg F 1.0F to 6F (default is 2F) (in 0.1F increments)
15 Cool Relay Span
This defines how far from the heating set point the stage 1 cool relay will energise to engage cooling or compressor. If
the SMT-400 is set for multistage cool control, then stage 2 also uses this value.
Adjustable range Deg C 0.5c to 3c (default is 1c) (in 0.1c increments)
Adjustable range Deg F 1.0F to 6F (default is 2F) (in 0.1F increments)

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16 Indoor Fan Reset
When the SMT-400 mode is set to OFF the fan, mode will change to the settings below.
0 Fan mode will remain unchanged –Continue in Fan Auto or Fan ON mode.
1If Fan On, Fan Mode will change to Auto mode and remain in Auto. (Default)
2 If Fan On, Fan Mode will change to Auto and remain in Auto. Fan button will be hidden.
3If Fan On, Fan mode will temporarily change to Auto and return fan on when SMT-400 is on.
4 If Fan On, Fan mode will temporarily change to Auto and return fan on when SMT-400 is on.
Fan button will be hidden while mode is off.
5 If enabled, the indoor fan mode will reset to Auto Fan Mode 1 hour after the thermostat mode is set to Off.
17 Fan Purge
The SMT-400 can ensure the evaporator fan runs past the heating and cooling calls if required.
0 No Fan Purge.
1 Fan Purge 1 minute.
2 Fan Purge 3 minutes.
3 Fan Purge 5 minutes.
4 Fan Purge 10 minutes.
5 Heat Only Mode Fan purge 1 Minute.
6 Heat Only Mode Fan purge 3 Minutes.
7 Heat Only Mode Fan purge 5 Minutes.
8 Heat Only Mode Fan purge 10 Minutes.
9 Cool Only Mode Fan purge 1 Minute.
10 Cool Only Mode Fan purge 3 Minutes.
11 Cool Only Mode Fan purge 5 Minutes.
12 Cool Only Mode Fan purge 10 Minutes.
18 Fan Span (3 Fan Speeds)
When the SMT-400 is set for 3 fan speeds, this option defines the temperature differential between fan stages.
Deg C 0.5C to 3.0C (1c Default) (Adjustment 0.1c steps)
Deg F 1.0F to 6.0F (2F Default) (Adjustment 0.1F steps)
19 W2 Relay Function
0 W2 relay is used as 2nd (or 3rd) stage Auxiliary heat. (Default)
Options below Only operates in single fan speed HP mode (SW1 = OFF, Sw2 = ON).
1 W2 relay is used to control an Emergency Heating system.
2 This will permit both Aux heat & Emergency Heating mode (both use W2 relay)
20 E. Heat Compressor
When option 19 is set for Emergency Heat, this option will define how the Heat Pump system operates when Emergency
Heat is running.
0 Compressor stops with E.Heat. (Default)
1Compressor still runs with E.Heat.
Note –This function DOES NOT interlock the fan with compressor output. If you wish the fan to come on with the
compressor in E.Heat mode turn on E.Heat Fan Below.
21 E. Heat Fan
When option 19 is set for Emergency Heat, this option will define how the Evaporator fan operates when Emergency
Heat is running.
0 Fan stops with E.Heat. (Default)
1Fan runs with E.Heat.

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22 Assignable Relay Functions
The SMT-400 has a volt free (2a @ 24V max) relay with changeover contacts that has a selection of functions. Some
functions have a threshold that can be applied to them, installer adjusts this threshold value option number 23 (below).
0 Relay not used
1Humidity Alarm
2Temperature Alarm
3 Occupancy Status (Relay energised when Occupied)
4 Heat Output –Energised whenever SMT-400 is demanding a heat.
50-10V heat Output –Energises whenever SMT-400 0-10v heat output is not 0V
6Cool Output –Energised whenever SMT-400 is demanding a cool.
70-10V cool Output –Energises whenever SMT-400 0-10v cool output is not 0V
8Heat & Cool Output –Energised when SMT-400 is demanding heat or cool.
90-10V heat & cool–Energises whenever the 0-10v Heat or cool output is not 0V
10 Fan output –Energised when SMT-400 Fan is running.
11 0-10V Fan out put - Energised when SMT-400 0-10v Fan is not 0v
12 Next Stage compressor (permits 2 compressor systems to run with 3 fan speeds).
13 Next Stage Heating. (HC mode).
14 Next Stage Cooling (HC mode).
15 CWP mode, the relay will output when heating or cooling is needed even if the SMT-400 is in fault mode.
16 The Assignable relay will be controlled via the Smart Temp Comfort App.
23 Assignable Relay Threshold
Where the assignable relay (as described above) automatically changes status based on a variable value (such as option
1 temperature or option 2 RH) this setting determines that threshold.
Range is 0 to 100. This can be deg C/F for temperature or 0-100% RH for example.
24 0-10v Output 1
25 0-10v Output 2
26 0-10v Output 3
The SMT-400 has 3 independent 0-10v outputs. Each output has the same library of functions. A more detailed
description of the 0-10V output functions can be found on page 26 of this manual.
0 Modbus Network Controlled (Default). The ModBus network can write a value to this output.
1 Heat Output –Used to control a valve or other heating device.
2Cool Output –Used to control a valve or other cooling device.
3Heat and Cool Output –Used to control capacity control device.
4 Fan output –used to control a DC fan.
5Fresh Air Damper –Used in economy cycle damper control.
6Return Air Damper –Used in economy cycle damper control.
7RH output –to provide an output in proportion to the current RH value.
8Belimo 6-way valve control –see page 25 for more information.
27 0-10v Heat Span
This value sets how far from set point the 0-10V heat output is at 10V.
Adjustable range Deg C 0.5c to 3c on 0.1c increments (default is 1c)
Adjustable range Deg F 1.0F to 6F on 0.1F increments (default is 2F)
28 0-10v Heat Interval (PI)
This value sets the time interval for the 0-10V Heat Valve Proportional Integral calculation.
Range 10 to 300 Seconds. (Default 60 seconds)
29 0-10v Heat Direction
To suit both forward and reverse action values, the 0-10V output direction for the heat valve can be defined.
0Forward acting 0 –10V
1 Reverse acting 10 –0V

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30 0-10v Heat Minimum Voltage
This is the lowest voltage that will be applied to the 0-10V Heat valve when the heating is called.
Adjustable range is 0.1 to 10V in 0.1v increments (default is 0.1v)
31 0-10v Cool Span
This value sets how far from set point the 0-10V cool output is at 10V.
Adjustable range Deg C 0.5c to 3c on 0.1c increments (default is 1c)
Adjustable range Deg F 1.0F to 6F on 0.1F increments (default is 2F)
32 0-10v Cool Interval (PI)
This value sets the time interval for the 0-10V Cool Valve Proportional Integral calculation.
Range 10 to 300 Seconds. (Default 60 seconds)
33 0-10v Cool Direction
To suit both forward and reverse action values, the 0-10V output direction for the cool valve can be defined.
0Forward acting 0 –10V
1 Reverse acting 10 –0V
34 0-10v Cool Minimum Voltage
This is the lowest voltage that will be applied to the 0-10V cool valve when the cooling is called.
Adjustable range is 0.1 to 10V in 0.1v increments (default is 0.1v)
Adjustable range Deg F 1.0F to 6F on 0.1F increments (default is 2F)
35 0-10v Fan Span
This value sets how far from set point the 0-10V Fan output is at 10V.
Adjustable range Deg C 0.5c to 3c on 0.1c increments (default is 1c)
Adjustable range Deg F 1.0F to 6F on 0.1F increments (default is 2F)
36 0-10V Fan Interval (PI)
This value sets the time interval for the 0-10V fan Proportional Integral calculation.
Range 10 to 300 Seconds. (Default 60 seconds)
37 0-10V Fan Direction
You can define the 0-10v logic for the control for 0-10V fan logic
0Forward action 0-10V= Slow to fast
1 Reverse action 10-0V = Slow to fast
38 0-10V Fan Minimum Voltage
To prevent a fan motor potentially running too slowly, the SMT-400 permits you to set a minimum fan run voltage. This
is the lowest voltage that will be applied to the fan when the fan is running.
Adjustable range is 0.1 to 10V in 0.1v increments (default is 0.1v)
39 0-10V Fan Maximum Voltage
To prevent excessive fan noise the fan motor maximum speed can be limited. This setting defines the highest voltage
that will be applied to the fan when the fan is running.
Adjustable range is 0.1 to 10V in 0.1v increments (default is 10V)