Carrier T--298 service manual Section Troubleshooting

SECTION 2

TROUBLESHOOTING

For ducted units, the green operation indicator LED (SeeFigure 3-9) will flash if there is a problem. Refer to Table 2--1 for diagnostic information.

	SYMPTOM AND PROBABLE CAUSE		PROBABLE REMEDY
2.1 NO POWER TO UNIT
1.	Master switch off	1.	Reset master switch
2.	Open circuit breaker	2.	Reset circuit breaker
3.	Defective wiring	3.	Replace wiring
4.	Loose electrical connections	4.	Tighten connections
5.	Faulty switches, thermostat, or fan	5.	Replace defective components
6.	12 VDC not connected (Ducted System)	6.	Connect to 12 VDC power source
7.	12 VDC in--line fuse open (Ducted)	7.	Replace fuse
2.2 DUCTED UNIT WILL NOT OPERATE
1.	Display not illuminated	1.	Check 12 Volt DC in--line fuse
2.	Display illuminated	2.	Check 115 Volt AC Connections
2.3 DUCTED UNIT WILL NOT COOL
1.	Green LED light flashes 5 times	1.	Check 115 volt AC power source
			Momentarily disconnect 12 VDC power source
			Disable compressor malfunction test switch.
			Check AMP draw.
			Check ∆ T
2.	Unit cools for a few moments then stops cooling	2.	Remove grill, verify evaporator coil probe is
			inserted into coil.
			Check AMP draw.
			Check ∆ T
			Replace unit
2.4 COMPRESSOR POWER SUPPLY OPEN
1.	Loose leads at compressor terminals	1.	Tighten leads
2.	Defective motor overload switch	2.	Replace switch
3.	Defective capacitor	3.	Replace capacitor -- Refer to Paragraph 3.5.8
4.	Open compressor windings	4.	Replace compressor
5.	Seized compressor	5.	Replace compressor
6.	Capacitor incorrectly wired	6.	Verify capacitor wiring (Refer to wiring diagram)
2.5 COMPRESSOR RUNS BUT CYCLES, FAN OPERATING ERRATICALLY
1.	Loose lead at fan motor	1. Tighten lead.
2.	Defective or burned out motor	2.	Replace motor.
3.	Outdoor air restricted or recirculating	3.	Check for dirty condenser coil, proper clearance
			around unit, remove any obstructions.
4.	Overcharge or noncondensables in system	4.	Check AMP draw
5.	Restricted discharge line	5.	Check for obstruction in line.
			Check ∆ T.
			Replace unit.
6.	Defective motor overload switch	6.	Replace switch.

2-1 T--298