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KOOLMASTER PP20-VS2 rev.00
KOOLMASTER PP20-VS2
6.3. Natural Ventilation
Curtains
The controller can control two natural ventila-
tion curtains. To operate these curtains, the
controller refers to the average temperature
reading of their assigned temperature probes
(see sec. 4.7.3).
Relation between Fan Stages &
Natural Ventilation Curtains
Curtain
Status
ON
ON
OFF
OFF
Set Point
Set Point
Close at
The curtain
closes in timer
mode
The curtain opens
in timer mode
Open at
Average T° of the
curtain’s probes
Stage
Activation
First tunnel
stage
Initial
opening T°
Stop
Natural
0.5°F
Natural
Ventilation
Status
Principle of Operation
6.3.1.
The controller enters in natural ventilation
when the average temperature of the probes
that are assigned to a curtain reaches the
Initial Opening Temperature
of the curtain. At
that moment, the curtain opens during its
Initial Opening Time.
GRAPH 1
From natural to tunnel ventilation
Temperature rises
Natural ventilation
Tunnel ventilation
1st tunnel
stage
(Open at)
(Close at)
When the natural ventilation mode is on, the
natural ventilation curtain moves in timer
mode: it opens according to its opening cycle
(Open Time & Off Time)
when the average tem-
perature rises above its opening temperature;
likewise, it closes according to its closing
cycle
(Close Time & Off Time)
when the tem-
perature falls below its closing temperature.
Natural ventilation is disabled when the average
temperature decreases of 5°F (2.8°C) below
the curtain’s closing temperature or when tun-
nel ventilation starts (see graph below).
Using Tunnel Doors in Natural Ventilation
When they are used in natural ventilation,
tunnel doors follow the same progression
as natural ventilation curtains (same timer
and temperature settings). Tunnel door 1
follows curtain 1, and tunnel door 2 follows
curtain 2.
6.3.2. Natural & Tunnel Vent.
Transition
1. Transition from Natural to Tun-
nel Vent.
When the room temperature reaches the
natural ventilation’s start temperature, the
natural curtain starts opening in timer mode
[A] – if tunnel doors are used in natural venti-
lation, they open according to the same timer.
When the room temperature reaches the start
temperature of the first tunnel stage [C], the
natural curtain stays still during the
“Tunnel
Close“
delay and then fully closes. Here’s how
a tunnel door opens at the startup of tunnel
ventilation:
If the tunnel door
1.
is not used in natural vent.:
The tunnel door opens to the position as-
sociated with the first tunnel stage. When it
reaches half the opening of that stage, the
controller turns on the fans.
If the tunnel door is used in natural vent.:
2.
The tunnel door fully opens and then goes
the position associated with the first tunnel
stage. This allows resetting the position of
the tunnel door before entering in tunnel
ventilation.
Summary of Contents for Koolmaster PP20-VS2
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