Bryant 187B Outdoor Air Thermistor OAT Attachment, Outdoor Coil Thermistor OCT Attachment, Amber

OAT Thermistor must be locked in place with spherical nib end facing towards the front of the control box

OCT Thermistor must be secured tight on the liquid tube.

Fig. 8 - Outdoor Air Thermistor (OAT) Attachment			Fig. 9 - Outdoor Coil Thermistor (OCT) Attachment
	Table 6 – TROUBLESHOOTING
		AMBER
OPERATION	FAULT	LED	POSSIBLE CAUSE AND ACTION
		FLASH
		CODE
Standby – no call for unit op-		On sol-
	None	id, no	Normal operation
eration
		flash
Low---stage Cool/Heat Opera-	None	1, pause	Normal operation
tion
High-stage Cool/Heat Opera-	None	2, pause	Normal operation
tion
	System Communications	16	Communication with user interface lost. Check wiring to User Interface, indoor
	Failure		and outdoor units
	Invalid Model Plug	25	Control does not detect a model plug or detects an invalid model plug. Unit
			will not operate without correct model plug.
	High Pressure Switch Open	31*	High---pressure switch trip. Check refrigerant charge, outdoor fan operation
			and coils for airflow restrictions.
	Low Pressure Switch Open	32*	Low pressure switch trip. Check refrigerant charge and indoor air flow
	Control Fault	45	Outdoor unit control board has failed. Control board needs to be replaced.
	Brown Out (230 v)	46	Line voltage < 187v for at least 4 seconds. Compressor and fan operation not
			allowed until voltage>190v. Verify line voltage.
			There is no 230v at the contactor when indoor unit is powered and cooling/
	No 230v at Unit	47	heating demand exists. Verify the disconnect is closed and 230v wiring is
			connected to the unit.
	Outdoor Air Temp Sensor	53	Outdoor air sensor not reading or out of range. Ohm out sensor and check
	Fault		wiring.
	Outdoor Coil Sensor Fault	55	Coil sensor not reading or out of range. Ohm out sensor and check wiring.
	Thermistors out of range	56	Improper relationship between coil sensor and outdoor air sensor. Ohm out
			sensors and check wiring.
			Compressor operation detected then disappears while low---stage demand
	Low stage Thermal Cutout	71*	exists. Possible causes are internal compressor overload trip or start relay and
			capacitor held in circuit too long(if installed)
			Compressor operation detected then disappears while high---stage demand
	High stage Thermal Cutout	72*	exists. Possible causes are internal compressor overload trip or start relay and
			capacitor held in circuit too long (if installed)
	Contactor Shorted	73	Compressor voltage sensed when no demand for compressor operation
			exists. Contactor may be stuck closed or there is a wiring error.
	No 230V at Compressor	74	Compressor voltage not sensed when compressor should be starting. Contac-
			tor may be stuck open or there is a wiring error.
	Low-stage Thermal Lockout	81	Thermal cutout occurs in three consecutive low/ high---stage cycles.
			low---stage locked out for 4 hours or until 24v power recycled.
	High-stage Thermal Lock-	82	Thermal cutout occurs in three consecutive high/low---stage cycles.
	out		high---stage locked out for 4 hours or until 24v power recycled.
	Low Pressure Lockout	83	Low pressure switch trip has occurred during 3 consecutive cycles. Unit oper-
			ation locked out for 4 hours or until 24v power recycled.
	High Pressure Lockout	84	High pressure switch trip has occurred during 3 consecutive cycles. Unit oper-
			ation locked out for 4 hours or until 24v power recycled.
* Sequence: Compressor contactor is de-energized and outdoor fan is energized for up to 15 minutes. If demand still exists, control will energize compressor.

187B / 180B

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