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10.7 EW-S controller
The EW-S controller controls the winter and
summer operation of the EW-system.
Wall assembly
To remove the front cover, fold both covers
away to the side (
→
arrow) and remove the
two screws.
Secure the housing lower part to the wall
using suitable installation material.
Cable the EW-S controller to the pump and
the mains in accordance with the
connection diagram in Chapter 10.7.4.
10.7.1 Winter operation
The outside air that is fed to the ventilation
system is warmed up in winter operation. Two
operating modes can be set for this purpose:
WRG or WP mode.
Winter operation is activated during
the months from November to March.
WRG mode
This mode is used if the EW-K 225 is connec-
ted to a heat recovery unit. The EW-K 225
extracts enough energy from the ground so
that the outside air temperature is frost-free.
The pump switches on if T1 and T2 < 0.5 °C.
It switches off when T2 > 3 °C after a
minimum pump runtime (approx. 5 min.).
WP mode
This setting is recommended, if:
●
The system is installed in a warm region
with mild winter temperatures
●
There is an advantageous ground
condition, direction or position.
●
a WP compact unit is installed downstream
from the EW-K 225.
●
an increasing number of frost messages
occur in a WRG unit.
More energy is extracted from the ground in
WP mode than in WRG mode.
The outside air temperature is heated at a
level b2 °C to +4 °C.
The pump switches on if T2 < 2 °C.
It switches off when T2 > 4 °C after a
minimum pump runtime (approx. 5 min.).
10.7.2 Summer operation
Cooled and dehumidified outside air is fed to
the ventilation system in summer operation.
The outside air temperature can be adjusted
in 1 °C steps from 18 °C to 26 °C.
Summer operation is activated during
the months from April to October.
If the internal energy counter is not
at 0 by August (energy balance not
regulated), the summer setpoint
temperature is lowered by 4 K but
not to a level below 18 °C.
10.7.3 EW-S technical data
●
Analogue inputs
2
(for PT 1000 temperature sensors)
●
Digital outputs
2
●
Nominal current for EHZ
max. 5 A
●
Pump rated voltage
230 V
Rated frequency
50 Hz
●
Nominal current for pump
max. 5 A
●
Connection RS232 interface
1
●
Display
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