Troubleshooting guide

Page 18 of 28 / OM 931-3
Second Circuit Faults
With the addition of the second circuit the fault recovery and
reset table has new faults for the second circuit (Table 10).
Table 10: Second Circuit Faults
● = Applies – = Does not apply
Fault Auto Recovery
Remote Reset Reset (Network
(Tenant Override) Command or Power)
Invalid Conguration Jumper Setting – – ●
Brownout ● – ●
HP2 – ● ●
LP1 ●* ● ●
LT2 (In Heating) ●* ● ●
LT2 (In Cooling) – ● ●
Sensor Room Temperature, LT1, LT2,
– – ●
Failure EWT (w/Boilerless EH Only)
– – ●
Condensate Overow ● – ●
EEPROM Failure – – –
* Auto Recover for the first two occurrences, lockout on the third occurrence within 24 hours, i.e., subject to “Intelligent Reset.”
Table 11: I/O Expansion Module Connections & Descriptions
H8 Description
Pin 1 Fan high speed normally open output
Pin 2 No connection
Pin 3 24 VAC Common
H3
Pin 1
Pin 2
Pin 3 For future development
Pin 4
Pin 5
Pin 6
H8
Dual compressor: compressor 2 normally
Pin 1 open output, all others fan medium speed
normally open
Pin 2 24 VAC common
Pin 3 No connection
Pin 4
Dual compressor: reversing valve for
circuit 2, all others electric heat
Pin 5 24 VAC common
H4
Pin 1 Entering water temperature sensor signal
Pin 2 Entering water temperature sensor common
HP6
HP2-1 High pressure switch for circuit 2
HP2-2 High pressure switch for circuit 2
H7
Pin 1 Suction line temperature sensor circuit 2 signal
Pin 2 Suction line temperature sensor circuit 2 common
Pin 3 Low pressure switch circuit 2 signal
Pin 4 Low pressure switch circuit 2 source
H5 LED Annunciator
TB1 For future use