Venstar T2900 Owner's Manual page 99

Explanation of Jumper Settings
ECON JUMPER SETTING
If the jumper for MISC2 or MISC3 is set to ECON,
terminal on the backplate will be connected to an economizer.
ECONOMIZER OPERATION - If your HVAC unit is equipped with an
economizer system, the thermostat will provide power to the MISC2 or
MISC3 terminal of the thermostat when the thermostat is in an occupied
time period. The MISC2 or MISC3 terminal will be de-energized when the
thermostat is in an unoccupied time period.
Y2 JUMPER SETTING
If the jumper for MISC1 is set to Y2 the
second stage of cooling.
Y2 OPERATION - Section 13
Control up to two Cool stages.
The 2nd Stage of heat or cool is turned on when:
(A) The 1st Stage has been on for the time required (step #27,
page 13.6). It is adjustable from 0-60 minutes and the default
is two minutes.
And
(B) The temperature spread from the setpoint is equal to or greater
than: the setpoint plus the deadband (step #24, page 13.5), plus
the 2nd deadband (step #25, page 13.5). This 2nd deadband is
adjustable from 0-10 degrees and the default is two degrees.
Deadband
db 1
(adj. 1-6 )
21
Cool
Setpoint
TEMPERATURE
(continued)
the corresponding MISC screw
MISC1 screw terminal on the backplate will control a
Cooling
Deadband
db 2
(adj. 0-10 )
1st Stage 2nd Stage
turn on turn on
INCREASE
Page 21.5