Honeywell T6861-F User manual

1
T6861-F Large LCD Digital Thermostat
230 VAC , Floating output
2-pipe fan coil control
Data sheet
Features
• Super modern appearance design, suitable for
ofce, hotel and residential building
• Horizontal and vertical model available for variant
application
• Slim design, direct installation on 86 size box
• Stylish and elegant blue/green backlight with white
• 2-pipe integrated into one unit with easy conguration
• Big LCD display with English and icons
• Easy to install and set-up
• Time on/off function
• Selectable room temperature or setpoint temperature
display
• Manual or automatic fan speed selection
• Remote sensor function
• Adjustment of display room temperature
• Temperature unit either oC or oF
• User setting can be kept when power off
• Freezing protection function available
• Lock or unlock keys or part of keys in Installer Set-up
• Heat and cool setpoint limitation for energy saving
Model summary
Application
T6861-F digital thermostats are designed for
application of 3-speed fan and oating valves in fan
coil system.
Including:
2-pipe cool only/heat only/manual changeover
Ventilation mode
Manual or automatic 3-speed fan control
oating valve control
Fan speed can be selected to automatic or manual
3-speed control mode.
In ventilation mode, fan only support manual speed
control.
Note: Horizontal models are taken as samples for display, operation and installation pictures shown in below parts.
Model Horizontal/
Vertical Backlight Color Ring Time on/off
2-pipe/
4-pipe
Power supply
(V)
Remote
sensor Ventilation Manual/ Automatic Fan
Remote
Setback
T6861H2WB-F Horizontal Blue White Y2 230 Y Y Y N
T6861V2WB-F Vertical Blue White Y2 230 Y Y Y N
T6861H2WG-F Horizontal Green White Y2 230 Y Y Y N
T6861V2WG-F Vertical Green White Y2 230 Y Y Y N

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Temperature display
The displayed temperature can be set to acquired
room temperature or setpoint. The setting can be
made during Installer Set-Up process.
Mechanical design
Thermostat appearnce
LCD display
Function
Floating Valve control
Thermostat acquires the room temperature via its
integrated sensor or external temperature sensor
and maintains the setpoint by delivering floating
valve control commands 3-position outputs.
Fan Operation
Fan can be selected as manual or automatic 3-speed
operation. In Manual mode, the fan is switched to
the selected speed via control output Gh, Gm, Gl.
While in automatic mode, fan speed depends on the
difference between room temperature and setpoint.
When room temperature reaches setpoint, valve will
be closed and meanwhile, fan will be closed either.
Time on/off
If the thermostat is off, hold power button for 3
seconds, system will be time on mode. If the
thermostat is on, hold power button for 3 seconds,
system will be time off mode.
The setting range is from 0 to 12 hours. The step is
0.5 hour with the default time is 0.
50030722-001 REV.A
DIGITAL DISPLAY
FAN BUTTON
POWER BUTTON
MODE BUTTON
UP BUTTON
DOWN BUTTON
PRESS THE FAN BUTTON TO SELECT
LOW, MED, HIGH OR AUTO
PRESS THE MODE BUTTON TO SELECT
HEAT, COOL, AUTO OR VENT
Fan speed ramping control algorithm
Open Degree of Valve
30%
70%
Fan speed is high
Fan speed is medium
Fan speed is low
100%
0

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Backlight
Any key press will activate the backlight. Backlights
will timeout 8 seconds after last key press. When
in Installer Set-up and Installer test mode, the
backlight will timeout 60 seconds after last key
press.
Keypad lock
Keypad lock can be set in ISU with default status
is all keys available. You may change into mode
button locked out, Fan and mode buttons locked out
and All buttons locked out by changing the ISU.
Ventilation mode
Press mode button to enter ventilation mode. In
ventilation mode, no output for oating valve while
the fan will operate according to selected fan speed.
Remote temperature sensor
T6861 provides control either depending on the
acquired room temperature or depends on the return
air temperature. The model of remote temperature
sensor is (NTC20K).
Operating modes
The following operating modes are available:
Comfort mode
In comfort mode, the setpoint can be changed by
pressing up and down button. Different applications
include cool only, heat only and manual heat/cool
changeover.
Freezing protection mode
Freezing protection can be selected as disabled
(default) or enabled. In freezing protection mode
(no such mode in cool only application), when
thermostat is in OFF mode while the acquired
temperature is below 6oC, the thermostat will start
heat mode until the temperature rises to 8oC or the
thermostat is turned on.
On/off mode
Pressing power button can switch between on and
off mode.
Technical specication
Power supply 230 (+10%, -10%) VAC
Frequency 50Hz
Control algorithm PI, oating output
Accuracy +/-1oC at 21oC
Rating capacity For 230V power supply:
10(2)A for fan load, 3(1)A for valve
Cycle times 100,000 times
Setpoint range 10~32oC
Display range 0~37oC
Installation Installed on 86×86mm
junction box or 3×3 inch.
Protection Class IP20
Environmental Operation temperature -18~49oC
Conditions Shipping temperature -35~65oC
Relative humidity 5~90%,
noncondensing
INDICATES THERMOSTAT
HAS BEEN SET TIME OFF
TEMPERATURE
SETTING
PRESS THIS BUTTON TO
RAISE THE TEMPERATURE
SETTING
INDICATES THERMOSTAT
HAS BEEN SET TIME OFF

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Application 3: 2 pipes 1 stage Heat or 1 stage Cool
MCO wiring diagram
Application 2: 2 pipes Cool only wiring diagram
1 Pull wires through wire hole.
Loosen screw terminals, insert wires into terminal
Block, then retighten screws.
Terminal Designations
Install the thermostat about 5 feet (1.5m) above the
oor in an area with good air circulation at average
temperature.
Do not install in locations where the thermostat can
be affected by:
• Drafts or dead spots behind doors and in corners
• Hot or cold air from ducts
• Sunlight or radiant heat from appliances
• Concealed pipes or chimneys
• Unheated/uncooled areas such as an outside wall
Installation & Commissioning
Figure 0-2 Typical wiring for 3-wire control in 2 pipe cooling only
Figure 0-3 Typical wiring for 3-wire control in 2 pipes 1H1C
Wiring diagram
Application 1: 2 pipes heat only wiring diagram
Figure 0-1 Typical wiring for 3-wire control in 2 pipe heating only
Terminal Description
L Line voltage Power
Ch/Cc Valve close
W/Y Valve open
NLine voltage ground
Gl Low speed fan relay
Gm Medium speed fan relay
Gh High speed fan relay
Sc Ground for remote sensor
Rs Remote sensor
Heat valve
Fan
remote sensor
Cool valve
Fan
remote sensor
valve
Fan
remote sensor

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2 Push the Power box into the junction box.
5 Align the 4 tabs on the Back cover with corresponding
slots on the back of the thermostat, and then push it
until the thermostat snaps in place.
4 Insert the cable into connector on circuit board of
thermostat.
3 Place Back cover over junction box, insert and
tighten mounting screws.
Installer system test
After completing the installer setup above, press the
button again to begin a system test
Follow the procedure below to test the heating and
cooling and fan system.
System
System test No.
Press and hold and buttons 3 seconds to enter
test mode.
Press or button to change system status.
Press button to advance to next test number.
Press and button hold to terminate system test
at any time.
System Test System Status
10 Valve open degree
0 Stop
1 Open
2 Close
40 Fan 0 Fan off
1 Low speed Fan on
2 Medium speed Fan on
3 High speed Fan on
70 Thermostat information (for reference only)
71 Software revision number (major revisions)
72 Software revision number (minor revisions)
73 Conguration identication code (major)
74 Conguration identication code (minor)
75 Production conguration date code (week)
76 Production conguration date code (year)
Installer Set-Up (ISU) setting
Press and simultaneously for 3 seconds to
enter ISU as below:
Press or to change settings
Press to advance to next function
Press and hold and buttons 3 seconds to
exit and save settings
Number
Setting

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Troubleshooting Tips
If… Then…
Valve doesn't
open
♦ Press Up and Down button and hold them about 3s.
♦ Press Mode button to adjust the item to "10", and
Press the Up button to modify the value to "2".
♦ Check the actuator. It must turn on slowly.
♦ Check the valve, if it still doesn't open, please call
your supplier.
The fan doesn’t
work.
♦ Check whether the Fan mode is set to Auto
♦ Check whether valve is open
The Mode
button doesn’t
work.
♦ Check whether the keypad is locked or not.
♦ Check whether the thermostat is off.
The Fan button
doesn’t work.
♦ Check whether the keypad is locked or not.
♦ Check whether the thermostat is off.
The Up or Down
button doesn’t
work.
♦ Check whether the keypad is locked or not.
♦ Check whether the thermostat is off.
Setup Function Settings & Options
ISU Code Description Possible Options
1System Type
0 Heat only
1 Cool only
2 Two pipes 1H1C manual (Default)
3Floating Actuator
Running Time
24 (120 seconds Default)
Range 6~32 (30~160 seconds)
5 Remote Sensor
0 Onboard Sensor (Default)
1 Remote sensor
(NTC20K, T7770A1006)
9 Temperature Scale
0 ºF
1 ºC (Default)
10 Fan Control Type
0 Auto Only
1 Constant Only
2 Both (Default)
18 Display Temperature
Adjustment
-2 ºC (-4 ºF)
-1.5 ºC (-3 ºF)
-1 ºC (-2 ºF)
-0.5 ºC (-1 ºF)
0 ºC (0 ºF) (Default)
0.5 ºC (1 ºF)
1 ºC (2 ºF)
1.5 ºC (3 ºF)
2 ºC (4 ºF)
19 Temperature Display
Mode
0 Display Room Temperature
1 Display Set point
2 Display Both (Default)
20 Heating Range
Stops
10-32 ºC Default 32 ºC
(50-90 ºF Default 90 ºF)
21 Cooling Range
Stops
10-32 ºC Default 10 ºC
(50-90 ºF Default 50 ºF)
22 Keypad Lockout
0 All keys are available (Default)
1 System button is Locked out
2 Fan and System button are Locked out
3 All buttons are locked out
27 Freeze Protection
0 Disabled
1 Enabled
Dimension
Horizontal model
Vertical model