Functions; Fan Speed Adjustment; Voltage And Current Signal Control; Heat Recovery Bypass - Helios KWL 500 W ET Notice De Montage Et D'utilisation

FUNCTIONS

Fan speed adjustment

Manuel control
Fan speed of the ventilation unit is controlled in 8 steps at the
control panel.
Automatically over exteral clock timer
The current supply to the KWL-unit can be controlled via an exter­
nal clock timer. The KWL-unit switches after the start-up to mini­
mum air flow capacity level, afterwards the air flow capacity con­
trol occurs on the basis by the air quality sensors transferred data
and/or by manual controlling of the remote control.
CO sensors and humidity control
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The fan capacity of the ventilation unit is controlled in multiple
steps depending on load, and based on the measuring results of
the air quality sensors (CO
ventilation zone. The aim is to keep CO
in the zone below the setpoint defined at the control panel. One
or more modes of control may be used simultaneously: The do­
minant mode is the one demanding boosting. Ventilation can be
adjusted in a maximum of 8 steps. Fan speed varies depending
on load between the basic and maximum fan speeds. The basic
and maximum fan speeds can be set at the desired level at the
control panel.

Voltage and current signal control

The fan capacity of the ventilation unit is controlled in 8 steps with
a voltage signal of 0 -10 VDC or a current signal of 0 -20 mA.
However, when automatic adjustments are enabled, fan capacity
cannot be raised above the set maximum fan speed. The voltage
or current signal control is used to control basic fan speed.
Because of this, fan speed can only be raised, but not lowered by
the manual, CO and %RF controls (See page 18, SS-817).
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Values for voltage and current signal control
Fan speed Voltage values (VDC)
for each fan speed
0 (0,20...1,25 VDC)
1 (1,75...2,25 VDC)
2 (2,75...3,25 VDC)
3 (3,75...4,25 VDC)
4 (4,75...5,25 VDC)
5 (5,75...6,25 VDC)
6 (6,75...7,25 VDC)
7 (7,75...8,25 VDC)
8 (8,75...10,00 VDC)
Choice of plug contacts for voltage and current signal control
On the mother board settings of the plug contacts
for voltage- and current signal can be carried out.
- Plug contact
voltage signal control.
(factory setting).
- Plug contact
current signal control.
(Kontakte gebrückt)
and humidity sensors) located in the
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and/or humidity content
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Current values (mA)
for each fan speed
(0,5...2,5 mA)
(3,5...4,5 mA)
(5,5...6,5 mA)
(7,5...8,5 mA)
(9,5...10,5 mA)
(11,5...12,5 mA)
(13,5...14,5 mA)
(15,5...16,5 mA)
(17,5...20,0 mA)

Heat recovery bypass

Heat recovery is enabled when the defined conditions on page
10 are fullfilled. In this case, the control unit directs the operation
of the damper motor on the basis of measuring results given by
the outdoor sensor and the extract air temperature sensor. The
aim is to get as cool supply air to the ventilation zone as possible.
Heat recovery is, however, on whenever outdoor temperature is
below the limit set, or whenever outdoor air is warmer than extract
air.

Heat recovery defrosting

Active when outdoor temperature is below 0 °C. The control centre
of the unit controls the operation of the preheating unit on the
basis of the measurement data given by the temperature sensors,
thus preventing freezing alerts and the intermittent stopping of
the supply air fan.
If the capacity of the preheater is not sufficient, or if there is no
preheater, the control centre intermittently stops the supply air fan
on the basis of the measuring data on the temperature sensors,
thereby preventing the heat recovery cell from freezing. As soon
as the risk of frosting passes, the fan restarts automatically. The
threshold temperature for defrosting (-6…+15 °C) and the
difference area (1…10 °C) can be set on the control panel. When
the supply air fan stops, power supply from the radiators is stopped
and the post-heating radiator continues heating.

Overheating protector of heating unit

The overheat protection thermostats monitors the surface
temperature of the preheating unit. The overheat protection
thermostats monitor the surface temperature of the preheating
unit. If surface temperature exceeds the threshold, overheat
protection is triggered and power supply to the heating unit is
stopped. The overheat protection thermostats are reset manually,
and automatically.

Maintenance/Alarms

Note for adjustments: Depending on atmospheric load, opera­
ting methode and environmental conditions of the KWL-Unit, a
longer or shorter maintenance cirle can be adjusted. Because of
hygienic causes a longer than 6 months circle is not recommen­
ded.
If the unit is not equipped with pressure difference switches, the
symbol ( ) appearing in the main display of the control panel
reminds of the need of servicing the unit. The reminder interval
can be set between 1…15 months. The factory setting is 4 months.
This function is always active.
The fault signal relay in the unit gives potential-free alarm indications
on the following fault conditions:
• Alarm of high carbon dioxide content (>5000 ppm ) switches
the relay at 1-second intervals. The fans stop, reset by switching
off the unit.
• In other fault situations, such as sensor faults and filter guard
alarms, the points of the relay close.
• Filter maintenance advice: Filters must be cleaned or replaced.

Booster or fireplace switch

The fireplace switch stops the extract air fan for 15 minutes and
produces overpressure in the ventilation zone.
1.Alternative:
An extra switch "S" may be connected to the connection box of
the ventilation unit to work as a booster or fireplace switch. The
operation mode of the switch is selected at the control panel. The
booster switch function raises fan speed to maximum speed for
45 minutes. The fireplace switch stops the extract air fan for 15
minutes and produces overpressure in the ventilation zone.
2. Alternative:
Press + and - buttons simultaneously at the control panel to
activate booster or fireplace switch.
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