Shutdowns And Lock-Outs; Blockage; Blocking - REMEHA Calenta 25s Installation And Service Manual

8. Troubleshooting
Error Description
code
Communication error
e[38
with the SCU PCB
Shutdown input in
e[39
locked-out mode
HRU/URC unit test error
e[40
8.2

Shutdowns and lock-outs

88
Probable causes
Bad connection
4
Defective SCU PCB
4
Bad connection
4
External cause
4
Parameter incorrectly
4
set
Bad connection
4
External cause
4
Parameter incorrectly
4
set
T001632-B
Checking / solution
Check the wiring
4
Replace SCU PCB
4
Check the wiring
4
Suppress the external cause
4
Check the parameters
4
Check the wiring
4
Suppress the external cause
4
Check the parameters
4
8.2.1.

Blockage

If the blocking conditions still exist after several start up attempts, the
boiler will switch into locking mode (fault). The boiler can only start
operating again once the causes of the lock-out have been rectified
and after pressing the > key.
8.2.2.

Blocking

A (temporary) blocking mode is a boiler operating function caused by
an unusual situation. In this case, the display gives a code of blocking
(code 5t[9). The boiler control will try to re-start several times.
The boiler will start up again after the blocking conditions have been
eliminated. The shutdown codes can be read out as follows:
1. Press the two f keys simultaneously.
2. Confirm by pressing key S . 5t is displayed, alternating with
the shutdown code 9 .
3. Press the [+] key. 5v appears on the display.
Calenta 25s - 28c - 35s - 40c
040412 - 7600585-01