Stulz EC Tower ECD 91 - 9. Error codes; Interface III k; Air conditioning unit

159 © STULZ GmbH – all rights reserved EN/01.2019/G22
ec tower technical manual
Problem Possible cause and remedy
In Program 8, air conditioning unit switches
off
or
In Program 8, wired remote control displays
E8
The indoor air conditioning unit is in
- anti-frost mode at heat exchanger temperatures < 2°C. The requested output
does not match the airflow or heat exchanger (Cooling mode).
- overheating protection mode at heat exchanger temperatures > 63°C. The
requested output does not match the airflow and heat exchanger (Heating
mode).
Remedy:
- Check requested output.
- Increase the flowrate.
- Use a larger heat exchanger.
- Check position of temperature sensors Thi-R1, Thi-R2, Thi-R3.
In Program 8, air conditioning unit starts up
despite 0V DC at analog input
010V DC analog signal
X3S is not evaluated correctly.
Remedy:
- Check signal at digital input X2b-D4. The analog input is only evaluated cor-
rectly if a signal is present (see “4.2.1 Evaluating the analog input“ on page
150).
9. Error codes
The 7-segment display displays two different types of error code.
InterfaceIIIk
The error codes of the InterfaceIIIk are shown with E on the 7-segment display.
Display examples:
E1, E8
See page 160 for a description of InterfaceIIIk error codes.
Air conditioning unit
The error codes of the air conditioning units are shown without “E” on the 7-segment display.
Display example:
09 (equals error code E09).
The error codes of the air conditioning unit are listed in the Technical Manual of the relevant air conditioning
unit series (see “2.4 Other applicable documents“ on page 145).