Trane RTHB Discharge superheat

[Miked1]

We have 2 Trane RTHB350 chillers installed in a hotel. Both of them trip on High discharge superheat. As far as I know discharge superheat is calculated by subtracting Saturated temperature from discharge temperature. I have 54 Deg C discharge temp and 34 Deg sat temp. this gives me 20 Deg superheat. The Trane panel shows 13.5 Deg. superheat and the superheat setpoint is 2.1 Deg. C. I have contacted Trane locally but nobody can help me. Do I have a PC board problem in that the calculation is incorrect or am I missing something.

[CV_Geardrive]

Hi,
There isno RTHB350. There is RTHB300 or RTHB380.
Isuppose that the unit is US unit and not Europe unit.
The unit“inside” run in English system. On the CLD, if you choose it, you can haveEurope (SI) system.
The oldUS units has a problem in translation of differential temperature.
If, forexample, you have 32°F differential temperature, you will see in SI system 0°Cinstead of 17,7°C.
So, turnthe unit to English system and then check the operation.
Check ifunits need condenser chemical clean and also check if you have refrigerantshortage.
Checkthe accuracy of sensors and compare the temperature/pressure, with a dischargegauge, with the reading of condenser saturated refrigerant temperature.
Checkalso the subcool with unit loaded.
Hope ithelp.
Regards,
CV

[Miked1]

Thank you CV. I will try the system in imperial readings and see if there is a difference in the calculations. My apologies the unit is a RTHB450 and not a 350 as mentioned.

Miked1