Signal For Requesting An External Heat Source (Ehs); External Alarm Input; Backup Heater Needed For Sanitary Hot Water; Terminal Strip Pin - CIAT Ereba Installation Guide

8.7 - Signal for requesting an External Heat Source
(EHS)
Between PINS 4 and N of the terminal strip (see Fig. 14),
there is an output (1ph ~ 230V, 2A max) that can be
programmed using the remote User Comfort Interface
(see the control manual, Installation Menu code 106).
Two different strategies are possible based on Outdoor Air
Temperature:
1) Turn off heat pump and activate backup heat source.
This function is activated when OAT < Temperature
set in NUI code 148 (default value -20°C). In this
region heat pump turns off and external backup is
activated following one of below logic (NUI CODE
154):
• Output always on (NUI CODE 154=0) assumes
backup has its own regulation.
• ON/OFF based on room temperature set point
(NUI CODE 154=1)
• ON/OFF based on water temperature set point
(CODE 154=2) in case NUI is not installed/
available.
2) Both heat pump and backup heat source activated in
case Heat Pump delivered power is not enough. This
function is activated when OAT < Temperature set in
NUI code 150 (but OAT > temperature set in NUI
code 148). In this region HP keeps working and
backup heater turns on if set point on water is not
reached by 5°C (value can be set with NUI CODE
152) for 10 minutes (value can be set with NUI
CODE 151). Backup heater turns off when set point
on water is reached again.

8.10 - Terminal strip pin

EREBA
Description
Additional external temperature probe
Sanitary Water Request
Maximum Frequency Reduction Compressor
3-way valve
1- External Heat Source Request
2- Defrost
1- Alarm
2- Ambient temperature reached
1- Backup heater needed for SHW
2- Humidifier
1- Trace heater
2- Additional WP
Alarm input
ON / OFF
NORMAL / ECO Mode
Heating / Cooling Mode
20
IMPORTAnT nOTIce: In case of shW activation
(pins 13-15 closed) heat pump will turn on and backup
heater will turn off. This will happen in both the above
strategies.
WARnInG: In case of ehs installation, it is mandatory
to install a thermal switch on the water circuit to protect
the system from too high water temperatures. This
protection item has to be located immediately
downstream the ehs.

8.8 - External alarm input

On PIN 21 of the terminal strip (see Fig. 14) an alarm
input (dry contact) is available to force of the unit.
When the contact is closed (Between pin 21 and 3) the
whole system is turned OFF (Unit OFF, WP OFF, GMC
alarm n° 2). When the dry contact open the system turns
ON and works in the last configuration.
It is possible to use this feature connected with different
external control systems and/or safety devices. For
example in case of danger an external safety device could
send an output alarm signal to close the contact. So the
outdoor unit turns off and remains in that condition until
the dry contact is reopened.

8.9 - Backup heater needed for sanitary hot water

When OAT < Temperature set in NUI code 148 (default
value -20°C), if Par 108 is set to 1, on pin 11 of the terminal
strip a signal is available to activate a backup source for
SHW production.
PIN Signal
23 - 24 Input (NTC 3kΩ @25°C)
13 - 15 Input (contact switch quality>25mA@12V)
13 - 14 Input (contact switch quality >25mA@12V)
10 - 18 - N Output 230Vac (18-N: Power supply, 10 signal)
4 - N Relay Output Contact
5 - N Relay Output Contact
11 - N Relay Output Contact
12 - N Relay Output Contact
21 - 3 Input (contact switch quality >25mA@12V)
6 - 3 Dry contact
8 - 3 Dry contact
7 - 3 Dry contact
Limits CS1B Installation Menu Code
N.A. 126
N.A. 153
N.A. 5 - 6
1 ph ~ 230V, 2A N.A.
106 - 148 -150
1 ph ~ 230V, 2A -151 - 152 -154
-155
1 ph ~ 230V, 2A 147
1 ph ~ 230V, 2A 107 - 108
1 ph ~ 230V, 2A 156 - 157
N.A. N.A.
N.A. N.A.
N.A. N.A.
N.A. N.A.