Ph Troubleshooting - Bosch IDS 2.0 Service Manual

Service Manual

12.3.16 PH Troubleshooting

LED display output:
Description:
Possible causes:
Table 44
Procedure:
Are you running in
force mode?
No
Check for abnormal
Is there still a fault
Is the system
under charged
Did T3/T5 sensor
Restart system
Figure 31
1) See Section 13.1
2) See Section 13.4
Bosch Thermotechnology Corp. | 07.2021
PH
Low discharge superheat protection.
 Poor heat exchange on coil (cooling mode – indoor coil, heating mode – outdoor coil)
 Fan motor failure (cooling mode – indoor fan, heating mode – outdoor fan)
 Service valves not open
 TXV/EEV/filter drier blocked
 Under charged
Yes
pressure 1
Yes
No
code?
Yes
Yes
No
Yes
fail 2
No
Is ambient
temperature >
120F?
No
No service required
Follow IOM to adjust
refrigerant
Replace T3/T5
Bosch IDS 2.0 | 57
Yes
Quit force mode
Data subject to change