Ok, As I see this is vendor firmware (or hardware trouble).
Device report all temperetature (and some other) sensors as 0, see hpicfPsTemp:
POWERSUPPLY-MIB::hpicfPsState.1 = INTEGER: psPowered(3)
|
POWERSUPPLY-MIB::hpicfPsState.2 = INTEGER: psPowered(3)
|
POWERSUPPLY-MIB::hpicfPsFailures.1 = Counter32: 0
|
POWERSUPPLY-MIB::hpicfPsFailures.2 = Counter32: 0
|
POWERSUPPLY-MIB::hpicfPsTemp.1 = INTEGER: 0
|
POWERSUPPLY-MIB::hpicfPsTemp.2 = INTEGER: 0
|
POWERSUPPLY-MIB::hpicfPsVoltageInfo.1 = STRING: AC 120V/240V
|
POWERSUPPLY-MIB::hpicfPsVoltageInfo.2 = STRING: AC 120V/240V
|
POWERSUPPLY-MIB::hpicfPsWattageCur.1 = INTEGER: 0
|
POWERSUPPLY-MIB::hpicfPsWattageCur.2 = INTEGER: 0
|
POWERSUPPLY-MIB::hpicfPsWattageMax.1 = INTEGER: 65
|
POWERSUPPLY-MIB::hpicfPsWattageMax.2 = INTEGER: 65
|
POWERSUPPLY-MIB::hpicfPsLastCall.1 = Counter32: 964244386
|
POWERSUPPLY-MIB::hpicfPsLastCall.2 = Counter32: 964244386
|
POWERSUPPLY-MIB::hpicfPsModel.1 = STRING: Not Av...
|
POWERSUPPLY-MIB::hpicfPsModel.2 = STRING: Not Av...
|
indirectly, this is confirmed by the fact that the power supply model is not correctly determined (see hpicfPsModel).
I will add ignore 0 (zero) values, but correctly is write to Vendor support (or check new firmware).
Seems as you not only updated Observium, but devices firmware too 
Just note, you use firmware WC.16.07.0003.
Latest in this series is WC.16.07.000*6*, and newest is WC.16.10.0009