Advanced setup options (ISU) (continued)
# ISU
ISU Name
350
Upstage Timer for Backup
Heat (TH4210U only)
365
Compressor Cycle Rate
(Stage 1)
370
Heating Cycle Rate (Stage 1)
375
Heating Cycle Rate Auxiliary
Heat (TH4210U only)
387
Compressor Protection
425
Adaptive Intelligent Recovery
430
Minimum Cool Setpoint
431
Maximum Heat Setpoint
435
Keypad Lockout
ISU Options (factory default in bold)
0 = Off
1 = 30 minutes
2 = 45 minutes
3 = 60 minutes
4 = 75 minutes
1 - 6
Note: This ISU is only displayed when Cool /Compressor Stage
is set to 1 stage. Cycle rate limits the maximum number of times
the system can cycle in a 1 hour period measured at a 50% load.
For example, when set to 3 CPH, at a 50% load, the most the
system will cycle is 3 times per hour (10 minutes on, 10 minutes
off). The system cycles less often when load conditions are less
than or greater than a 50% load.
1 - 12
Note: This ISU is only displayed when Heat Stage is set to 1 stage.
Cycle rate limits the maximum number of times the system can
cycle in a 1 hour period measured at a 50% load. For example,
when set to 3 CPH, at a 50% load, the most the system will cycle
is 3 times per hour (10 minutes on, 10 minutes off). The system
cycles less often when load conditions are less than or greater
than a 50% load. The recommended (default) cycle rate settings
are below for each heating equipment type: Standard Efficiency
Gas Forced Air = 5 CPH; High Efficiency Gas Forced Air = 3 CPH;
Oil Forced Air = 5 CPH; Electric Forced Air = 9 CPH; Fan Coil = 3
CPH; Hot Water Radiant Heat = 3 CPH; Steam = 1 CPH.
1 - 12
0 = Off
1 - 5 minutes
Note: The thermostat has a built in compressor protection
(minimum off timer) that prevents the compressor from restarting
too early after a shutdown. The minimum-off timer is activated
after the compressor turns off. If there is a call during the
minimum-off timer, the thermostat shows "Wait" in the display.
This ISU is displayed if ISU 220 is set to at least 1 stage.
0 = No
1 = Yes
Note: Adaptive Intelligent Recovery (AIR) is a comfort setting.
Heating or cooling equipment will turn on earlier, ensuring the
indoor temperature will match the setpoint at the scheduled time.
50 °F to 99 °F (50 °F)
10.0 °C to 37.0 °C (10.0 °C)
Note: The cool temperature cannot be set below this level.
40 °F to 90 °F (90 °F)
4.5 °C to 32.0 °C (32 °C)
Note: The heat temperature cannot be set above this level.
Setting on original T4 models:
0 = None
1 = Partial
2 = Full
Note: Due to customer feedback this feature was changed. On
the original software you can lockout the thermostat from the
ISU the same as you can from menu lockout. For later versions,
this setting allows the contractor to enable or disable the lockout
feature. When disabled, there is no lockout option under menu.
Lockout code is 1234.
15
5 = 90 minutes
6 = 2 hours
7 = 3 hours
8 = 4 hours
10 = 5 hours
Setting on current T4 models:
0 = Disabled
1 = Enabled