Auxiliary Accessories Connection (Fig. 14); 3-Way Valve; Frequency Limitation; Stop Unit Or Defrosting Signals - CIAT Ereba Installation Guide

8 - auxIlIary acceSSorIeS connecTIon (fIg. 14)

8.1 - 3-way valve

The EREBA units drive a 3-way valve to manage a
sanitary water storage tank. The operating logic provides
that, in case of a request for sanitary water by an
accumulation tank, the system controls a 3-way valve to
direct the hot water only to the tank and to operate at the
maximum capacity to provide water at 60 °C (compatible
with the operating envelope).
For operation, connect the 3-way valve between PINS 18,
N and 10 of the terminal strip (see Fig. 14). PINS 18 (Line)
and N (Neutral) power the valve (1ph ~ 230V, 2A max),
and a command signal (1ph ~ 230V, 2A max) is available
on PIN 10.
If using a valve with spring return, only connect PINS 10
and N.
The sanitary water request signal must be a Dry Contact
type (contact quality greater than 25mA @ 12V) that
closes the circuit between PINS 15 and 13 of the terminal
strip (see Fig. 14).
ATTenTIOn: The sanitary water request has higher
priority than the programmed operating mode in both
heating and cooling mode.

8.2 - frequency limitation

To force the unit to operate at a lower maximum
frequency (to reduce noise) in the absence of a User
Comfort Interface, provide a Dry Contact (contact quality
greater than 25mA @ 12V) between PINS 13 and 14 of the
terminal strip (see Fig. 14). With the contact closed, the
unit will operate with a maximum frequency lower than
the standard one, otherwise it will operate in standard
mode.
For correct operation, it is necessary to configure the unit
using parameters 5 and 6 from the User Interface menu of
the CS1B.
The maximum noise reduction is about 3dB at 75% of the
maximum operating frequency of the compressor.

8.3 - Stop unit or defrosting signals

There are several signals available on the terminal strip to
indicate particular conditions or the stop of the external
unit.
The available signals are:
• Defrosting: When operating in Heating mode,
depending on the external environmental conditions,
the unit could perform defrosting cycles to clean the
external battery of any ice formations. Under these
conditions, it is not possible to guarantee the
requested temperature output water temperature,
which could reduce general comfort.
(PINS: 4-N, NUI CODE: 106 or 108)
• Alarm: Indicates an alarm condition that stops the
compressor. (PINS: 5-N, NUI CODE: 147 or 108)
• Ambient Temperature Reached: If suitably
programmed using the User Comfort Interface (NUI),
and operating with this interface, a signal is provided
that indicates that the pre-set temperature has been
reached. This signal can be used as the contact
window normally implemented in the fan-coils.
(PINS: 5-N, NUI CODE:147)
Several outputs are used for more than one condition.
It is possible to configure these outputs through the
User Comfort Interface installation menu (refer to
the CS1B manual).
Refer to the tables on the next two pages for the
correct pin-outs and use of the signals.

8.4 - External temperature probe

If the positioning of the external unit could induce a
non-representative reading of the external temperature by
the probe positioned on the machine, an additional
temperature probe can be provided (NTC 2 wire, 3kΩ @
25°C) remote. Connect the terminals of the probe between
PINS 23 and 24 of the terminal strip (see Fig. 14).

8.5 - dehumidifier or humidifier

A Dehumidifier or a Humidifier can be driven by EREBA
using humidity sensor into CS1B interface.
Connect electrically a Dehumidifier or a Humidifier to N,
11 terminals to a relay that drives Dehumidifier (NO
contact) or a Humidifier (NC contact) Configure NUI
code 108 (2 for dehumidifier /Humid.)
Configure ambient humidity limit (NUI CODE 107)
where Dehumidifier or a Humidifier is activated (eg. with
code 107 = 65, Dehumidifier is activated with ambient
humidity >UR65% 5% hysteresis).

8.6 - Additional water pump (ADD WP)

It is possible to connect an additional water pump through
the pins 12 and N. It is managed in the following way:
If OAT > temperature set in NUI code 148.
The additional water pump activation depending by the
NUI code 156.
1. ON/ OFF depending on the outdoor unit water pump
logic, in case of SHW activation ADD WP is ON;
2. ON/ OFF depending on the outdoor unit water pump
logic, in case of SHW activation ADD WP is OFF;
If OAT < temperature set in NUI code 148.
The additional water pump activation depending by the
NUI code 157 (0. always of, 1. on/of depending by EHS, 2.
always on).
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