Venstar T1900 - Manual (Page 66)

Page 14.4
The above figure assumes the minimum on time for the prior stage has
been met to allow the next stage to turn on; once the deadbands have
been exceeded.
Heat
Setpoint
Cool
Setpoint
Deadband Deadband Deadband Deadband Deadband
db 1 db 1 db 2 db 2 db 3
(adj. 1-6 ) (adj. 0-10 ) (adj. 0-10 ) (adj. 0-10 ) (adj. 1-6 )
1st Stage
turn on
2nd Stage
turn on
3rd Stage
turn on
1st Stage
turn on
2nd Stage
turn on
Heating Cooling
TEMPERATURE DECREASE INCREASE
Adjusting the Deadband
MULTI-STAGE OPERATION - Controls up to three Heat and two Cool
stages.
The 2nd Stage of heat or cool is
(A) The 1st Stage has been on for the time required (step #28,
page 14.6). It is adjustable from 0-60 minutes and the default
is two minutes.
(B) The temperature spread from the setpoint is equal to or greater
than: the setpoint plus the 1st stage deadband (step #25, next
page), plus the 2nd stage deadband (step #26, next page).
This 2nd stage deadband is adjustable from 0-10 degrees and
the default is two degrees.
The 3rd Stage of Heat is turned on when:
(A) The 2nd stage has been on for the time required (step #29,
page 14.6). It is adjustable from 0-60 minutes and the default
is two minutes.
(B) The temperature from the setpoint is equal to or greater
than: the setpoint plus the 1st stage deadband (step #25,
next page), plus the 2nd stage deadband (step #26, next
page) plus the 3rd stage deadband (step #27, next page).
This 3rd stage deadband is adjustable from 0-10 degrees
and the default is two degrees.
turned on when:
And
And
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