Honeywell TB8575 Thermostat User Manual


 
TB6575/TB8575 DIGITAL FAN COIL THERMOSTATS
15 62-0311—13
3. After the desired value displays, press the System
button to store your value selection and display the
next IT code.
NOTE: Exiting Installer Test Mode is the same as the
method for entering test mode,
Fig. 25. Installer Test (IT) mode screen.
OPERATION
PROPORTIONAL + 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 con-
trol errors of proportional-only control, but it
is slower to react to large temperature or set-
point changes.
Economy Setback Modes
ACTIVITY SENSING (IS 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 (IS 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 (IS 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 (IS) 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
(IS CODE #20).
For Cool Mode, when Economy Setback is enabled, the
set point changes to the remote setback cooling setpoint
(IS 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.
Fig. 26 illustrates the relationship between setpoints,
Remote Setback, and deadband for auto changeover with
heat and cool setpoints.
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
0Close
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 (IS 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