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TB6575/TB8575 DIGITAL FAN COIL THERMOSTATS
62-0311—05
14
NOTE: Exiting Installer Test Mode is the same as the
method for entering test mode,
Fig. 25. Installer Test (IT) mode screen.
OPERATION
PROPOR INTEGRAL
(P+I) CONTROL
Like a mechanical thermostat, the fan coil thermostats
have On/Off control output. However, this output is
regulated by a P+I algorithm, enabling the thermostat to
control closer to setpoint than conventional thermostats.
This results in performance where the space temperature
is maintained within 0.75°C (1.5°F) of the setpoint
regardless of fan speed.
NOTE: Integral action corrects the temperature control
errors of proportional-only control, but it is slower
to react to large temperature or setpoint
changes.
Economy Setback Modes
ACTIVITY SENSING (ISU CODE #22)
If Activity Sensing is enabled, any time the thermostat is
not touched (no single key is pressed) for the duration
selected, the thermostat automatically falls back into the
Economy Setback. The LCD displays ECONOMY
SETBACK just to the right of the main temperature
display to indicate Activity Sensing mode is active. When
any key is pressed, the thermostat controls to Occupied
mode.
BUTTON PRESS SETBACK (ISU CODE #19-5)
The default remote setback option is for economy setback
via a button press on the thermostat. In this mode, the
thermostat can quickly be setback by pressing and
holding down the System Mode button for more than 3
seconds. The LCD displays ECONOMY SETBACK just to
the right of the main temperature display to indicate the
Setback is active. When any key is pressed, the
thermostat controls to Occupied mode.
REMOTE SETBACK (ISU CODE #19)
Remote Setback is activated by a dry contact closure on
the remote setback input from an occupancy sensor, time
switch, or hotel card key. The thermostat controls to the
user/installer defined setback setpoints for increased
energy savings. The LCD displays Economy Setback just
to the right of the main temperature display to indicate the
Remote Setback mode is active.
When Remote Setback is active, all buttons on the
thermostat are disabled. However, the button
combinations to access Installer Setup (ISU) and Installer
Test (IT) remain enabled.
ECONOMY SETBACK OPERATION
For Heat Mode, when Economy Setback is enabled, the
set point changes to the remote setback heating setpoint
(ISU CODE #20).
For Cool Mode, when Economy Setback is enabled, the
set point changes to the remote setback cooling setpoint
(ISU CODE #21).
For 4 pipe applications with Auto Changeover and Heat/
Cool Setpoints, when Economy Setback is enabled, the
cool setpoint changes to the remote setback cooling
setpoint and the heat setpoint changes to the remote
setback heating setpoint. The new effective deadband is
the difference between the remote setback heating
setpoint and the remote setback cooling setpoint.
Table 5. Installer Test (IT) Codes and Options.
IT
Code
Code
Description
Option
Value
Option Description
10
Heat Control
0
Close
1
Open
20
Auxiliary Heat
Control
0
Close
1
Open
30
Cool Control
0
Close
1
Open
40
Fan Control
0
Close
1
Low Speed
2
Medium Speed
3
High Speed
50
Pipe Sensor
32-199 Displays the pipe
sensor temperature.
Only used for System
Type 3 or 6 (ISU code
#2, value 3 or 6). Only
the Analog pipe sensor
is tested.
71
Software Main
version
01-99 A 2-digit number, 01-99
72
Software Vice
version
01-99 A 2-digit number, 01-99
73
Configuration
Data Main version
01-99 A 2-digit number, 01-99
74
Configuration
Data Vice version
01-99 A 2-digit number, 01-99
75
Week Produced
01-52 A 2-digit number, 01-52
76
Year Produced
08-99 A 2-digit number, 08-99
M27587
Test