Bosch HP270-2 Technical Manual page 53

Note:
The following troubleshooting procedure is applicable to the new range
Code A09 – Warning Message
Possible water shortage
Note: Even if after A09 display the problem is overcome, message is kept until set point achievement.
Compressor re-tries operation at end of 1 hour after stop with warning activation. If failure is present for more than
12 h with consecutive tentative of HP operation, the failure displayed will be E09.
Failure in High Pressure Side:
Compressor in Operation > 30 min
before warning
High Pressure Switch / compressor
thermal protection activation due to
high gas pressure
Code A11 – Warning Message
Low Thermal Power (detected by T top due to slow temperature increase )
Existence of
recirculation?
Recirculation not
existent?
Page 53 from 56
Water shortage ?
Water flow through condenser
is as specified?
NTC sensor top out of
pocket?
Check pump size / pipe diameter / recirculation control as
continuous flow for recirculation loop dissipates thermal
energy from tank in installation
Ensure that recirculation have thermostat / timer for
temperature and operation control
Gas leakage / check for evidences for R134a
leakage as low gas charge decrease thermal power
6-720-821-364 SM HP270 – 250 - 200 2016/12 en
(HP 200_250-1 / 270-3)
Yes
Check air presence and
purge hydraulic circuit in
module
pump will turn at maximum speed)
No
No
Ensure circulation pump is
operative and ensure plate
heat exchanger is free of
Yes
Yes
Correct position and ensure
enter +/- 30 cm (until white
(HP 200_250-1 / 270-3)
(set PURG mode –
sediments / debris
sticker)