Emerson 2 user manual Troubleshooting guide, Problem Probable Cause Remedy

Troubleshooting

8.0TROUBLESHOOTING

Table 14 Troubleshooting guide

Problem	Probable Cause	Remedy
Unit will not start	No power to unit	Check voltage to input circuit breaker.
	Control voltage circuit	Locate short and reset breaker.
	breaker open
	Shut off by external	Check operation of thermostat.
	thermostat or stat is
	defective
No cooling	Low refrigerant	Check with gauges.
	charge
	Compressor contactor	Check voltage at contactor. If not present refer to print and determine
	not pulling in	voltage loss. Check enthalpy sensor for full CCW or D setting.
	No output from	Check operation of stat. Should have voltage output to Y terminal during
	thermostat	cooling.
Unit cycles on	Loss or restriction of	Check condenser blower assembly for proper operation. Check for dirty
high pressure switch	air flow	coil or inlet grille restriction.
	Defective fan cycling	Switch should make @ 240 PSIG ±10 (1655 kPa ±68.9). (Check settings
	control	on adjustable switch when supplied.)
Heat does not operate	No voltage output	Check stat for proper output to W terminal.
	from thermostat
	Fuseable link blown	Check for open and replace.
	Bad contactor	Check for open and replace.

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