User Guide

6-10 • E2 RX/BX/CX I&O Manual 026-1610 Rev 13 14-SEP-2011
The Comfort Alert diagnostic alarms are configurable
in the E2 as Disabled, Failure, Alarm, or Notice with an
accompanying priority setting. All Comfort Alert codes
will share the same advisory type and priority parameters.
High/Low Occ/Unocc Space Temperature Alarms
The thermostat does not provide alarming information
on either high or low temperatures for the Space tempera-
ture sensor. Therefore, the E2 application will provide this
functionality.
Supply Sensor Fail Alarm
The thermostat does not provide alarm information on
a failure of the supply temperature probe (if installed). The
E2 application will provide this functionality. Advisory
type, priority, and delay is provided for the supply sensor
fail advisory.
Conditions for Return to Normal (RTN) on Diag-
nostic Codes
The E2 application will issue an RTN on an active
advisory when the corresponding bit of the diagnostic
code goes to zero. If multiple diagnostic advisories are
active simultaneously, they will all return to normal when
the code reads zero.
Open Circuit Compressor open circuit. • Outdoor unit power disconnect is open.
• Compressor circuit breaker or fuse(s) is
open.
• Compressor contactor has failed open.
• High pressure switch is open and requires
manual reset.
• Open circuit in compressor supply wiring or
connections.
• Unusually long compressor protector reset
time due to extreme ambient temperature.
• Compressor windings are damaged.
Compressor open circuit
Open Start CircuitCompressor current only in run
circuit.
• Run capacitor has failed
• Open circuit in compressor start wiring or
connections.
• Compressor start winding is damaged.
Compressor open start circuit
Open Run Circuit Compressor current only in start
circuit.
• Open circuit in compressor run wiring or
connections.
• Compressor run winding is damaged.
Compressor open run circuit
Welded ContactorCompressor always runs. • Compressor contactor has failed closed
• Thermostat demand signal is not connected
to module.
Welded Contactor
Low Voltage Control circuit < 17VAC. • Control circuit transformer is overloaded
• Low line voltage (contact utility if voltage at
disconnect is low)
Compressor Low Volt Trip
Protector Trip Thermostat demand signal Y is
present, but the compressor is not
running.
• Compressor protector is open.
• Outdoor unit power disconnect is open.
• Compressor circuit breaker or fuse(s) is
open.
• Broken wire or connector is not making con-
tact.
• High pressure switch open if present in sys-
tem.
• Compressor contactor has failed open.
Protector Trip
Comfort Alert Descriptions Cause E2 Advisory
Table 6-6
-Comfort Alert Outputs