Sinclair SCV-EB Series Service Manual page 50

5.7 E3, H2, H3, Ed, HA, H5, H9 Troubleshooting
5.7.1 Digital display output
5.7.2 Description
 E3 indicates total outlet water temperature sensor(T1) malfunction
 H2 indicates liquid refrigerant temperature sensor(T2) malfunction
 H3 indicates gas refrigerant temperature sensor(T2B) malfunction
 Ed indicates inlet water temperature sensor (Tw_in) malfunction
 HA indicates outlet water temperature sensor (Tw_out) malfunction
 H5 indicates room temperature sensor(Ta) malfunction
 H9 indicates outlet water for zone 2 temperature sensor (Tw2) malfunction.
 Eb indicates solar temperature sensor(Tsolar) malfunction
 E7 indicates buffer tank upper temperature sensor(Tbt) malfunction
 Heat pump stops running.
 Error code is displayed on the refrigerant system PCB digital tube and user interface.
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