Paul santos 570 DC, Operating Manual, Page: 32 / 44

28 System Functions EN
A8
Malfunction
Frost protection device too hot
Bypass damper
functioning correctly in relation
to frost protection device?
(check with P76 to 1)
Yes
Check following sources of malfunctions:
(volume flow rate to low)
- Fans setting too low
- Supply air valves closed to tight
- Supply air duct blocked /
outdoor air intake closed
No
See malfunction code A5/A6
At block "Active self-test"
A7
Malfunction
Frost protection element does
not warm up (sufficiently)
Isolate from mains supply!
Remove filters,
plastic front
and sealing plate
Remove the connector of
frost protection device from the PCB
Yes
Remove heat exchanger
and frost protection device
Cable resistance
of frost protection device
infinite?
Yes
Check PCB fuse;
replace cable
No
Resistance
of T1 OK?
Replace temperature
sensor T1
Caution:
Reset unit
Check frost protection device
in conjunction with cable
Remove filters,
plastic front
and seal
WARNING!
Danger of death from
live components –
do not touch the PCB!
WARNING!
Danger of death from
live components –
do not touch the PCB!
Resistance measured
at connector
of frost protection device
> 300 Ohm?
Yes
No
No
A5 / A6
Malfunction bypass motor / frost
protection device
Remove filters,
plastic front
and sealing plate
Activate self-test
(P76 to 1)
Motor running?
Yes No
Isolate from mains supply
Remove motor and the
gearwheel with plastic part
Gearwheel defective?
No
Check connection on PCB;
12 VDC must be applied
if the motor is to operate
(see menu P76)
Power applied
to PCB?
Yes Yes No
Isolate from mains supply!
Replace PCB
ATTENTION:
Reset unit
Isolate from mains supply!
Replace motor
Replace
motor
Replace
gearwheel
WARNING!
Danger of death from
live components –
do not touch the PCB!