Specifications

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6720649497 SM HP270-1 2012/09 en
7.1 Failures prevention and detection
The design data supplied by Bosch must be known by authorized service partner’s technicians, in order to prevent
and avoid the following problems, nevertheless, the service partner is responsible to prepare technicians in such a
way that the following problems will never happen in the field with an end user.
- Refrigerant leaks after repairs and / or components replacement;
- Defective soldering or damaged components due to lack of knowledge in this area;
- Maintenance operations without recovery of refrigerant gas and correspondent treatment according
country laws and directives;
The vacuum of the system can be done using the two available charging probes, and must be performed correctly
in order to guarantee no moisture inside of refrigeration system.
The filter dryer must be replaced every time that the refrigeration system is opened and serviced, in order to avoid
reading the saturation point.
The bulb position must be ensured, in the top position after the evaporator, to allow a correct reading and a proper
functionality of the expansion valve.
In case of HMI replacement, respect and assemble the NTCs in the correct position to avoid wrong temperature
detection.
For the analysis of common failures (even without error code), the following material is recommend in
order to ensure a better detection of the origin of the malfunction by the refrigerant circuit technician.
Pict.57 – Tools for working pressure measurement in both high and low pressure side
Table 9 indicates the design data of the heat pump, in order to allow the refrigerant technician to repair, make
vacuum and re-charge the R134a in the unit in case of malfunction detection in the refrigeration circuit.
Temperature (ºC) Pressure (Bar) Temperature (ºC) Pressure (Bar)
-30 0.84 15 4.88
-25 1.06 20 5.72
-20 1.33 25 6.65
-15 1.64 30 7.7
-10 2.01 35 8.87
-5 2.43 40 10.17
0 2.93 45 11.6
5 3.5 50 13.18
10 4.15
Table 9 – Working pressures and temperatures