Alarms and Troubleshooting
OAU-SVX02F-EN
55
RTRM Failure Modes
Following is the listing of RTRM failure indication causes.
System Failure
Check the voltage between RTRM terminals 6 and 9 on J6,
it should read approximately 32 Vdc. If no voltage is
present, a System failure has occurred. Refer to
in
“Microprocessor Control,” p. 53
troubleshooting procedure.
Cooling Failure
CLP1 has opened during the 3 minute minimum “on time”
during four consecutive compressor starts, check CLP1 by
testing voltage between the J1-8 and J3-2 terminals on the
RTRM and ground. If 24 Vac is present, the CLP has not
tripped. If no voltage is present, CLP has tripped.
System Failure
Measure the voltage between terminals J6-9 and J6-6.
Normal Operation = approximately 32 Vdc
System Failure = less than 1 Vdc, approximately 0.75 Vdc
Cool Failure
Measure the voltage between terminals J6-8 and J6-6.
Cool Operating = approximately 32 Vdc
Cool Off = less than 1 Vdc, approximately 0.75 Vdc
Cooling Failure = voltage alternates between 32 Vdc and
0.75 Vdc
Unit Trips Heater
High Limit
High fire gas manifold pressure too high
Supply fan speed too low
Dirty or clogged filters
Restricted discharge air duct
Temperature of air entering heater too high
Defective high limit
Protonode Not
Communicating
Change Baud rate on UC600 to 38,400
WARNING
Live Electrical Components!
Failure to follow all electrical safety precautions when
exposed to live electrical components could result in
death or serious injury. When necessary to work with
live electrical components, have a qualified licensed
electrician or other individual who has been properly
trained in handling live electrical components perform
these tasks.
AVERTISSEMENT
Composants électriques sous tension !
Le non-respect de toutes les consignes de sécurité lors
de la manipulation de composants électriques sous
tension peut entraîner des blessures graves, voire
mortelles. S’il est nécessaire de travailler avec des
composants électriques sous tension, demandez à un
électricien qualifié et agréé ou à une autre personne
ayant la formation nécessaire pour manipuler des
composants électriques sous tension d’exécuter ces
tâches.
Table 15. TOAU UC600 troubleshooting (continued)
Trouble
Possible Cause