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INTER 2V4SA, rev.02
INTER 2V4SA
8.
Minimum Ventilation
Cycles
8.1. Principle of Operation
Definition:
Minimum ventilation cycles are
activated when the room temperature is
lower than the set point. Running the fans
even though ventilation is not required for
reducing the room temperature is useful to
reduce humidity levels and supply oxygen
to the room. It also prevents the fans from
freezing in winter.
Minimum Ventilation Timer:
During the
"On Time"
, the fans of stage 1 run at their
minimum speed and Stage 1 status LED is
on; during the
"Off Time"
, the fans return
to a stop and the status LED switches off.
Note that the minimum speed of stage 1 can
automatically be adjusted over time with a
ramp (see below).
Min.Vent
Status
ON
OFF
Time
On Time
Off
Time
Minimum
Ventilation Timer
The controller supplies maximum voltage
to the variable-speed fans for 2 seconds
at each start-up.
8.2. Minimum Ventilation
Timer Settings
The On and Off Times of the minimum ventila-
tion timer can be adjusted between 0 and 900
seconds, in increments of 15 seconds.
To run the fans continuously at minimum
speed, set the Off Time to zero and On
Time to any value other than zero.
To stop the fans, set the On Time to
zero and Off Time to any value.
To run the fans intermittently, set the
On Time to the desired running time and
Off Time to the desired off time.
• Select the
STAGE 1 BANDWIDTH/TIMER
menu.
• Press the Other Functions button. The
On Time of stage 1 flashes on the display
"
t. On
".
• Use the adjustment buttons to set it to the
desired value.
• Press the Other Functions button. The
Off Time of stage 1 flashes on the display
"
t. Off
".
• Use the adjustment buttons to set it to the
desired value.
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INTER 2V4SA, rev.02
INTER 2V4SA
7.1.2. De-icing of Stage 2 Fans
Stage 2 fans can automatically be de-iced
in cold weather conditions. When a de-icing
cycle starts, Stage 1 fans are stopped then
stage 2 fans start running at full speed for
2 seconds. Stage 2 fans then run at the
minimum speed of stage 2 during the de-icing
time. Once the de-icing time has elapsed,
stage 2 fans stop and the operation of stage
1 is resumed. Set internal switch #11 to ON
to enable the de-icing function.
De-icing
Status
ON
OFF
Time
De-icing
time
Cycle
Time
De-icing Timer
