Heat Controller DXM2 Functional Troubleshooting cont, ESD - ERV Fault DXM Only, Unit Short Cycles

Heat Controller, Inc.DXM2 UNIT CONTROLS Application, Operation, & Maintenance Manual

				Functional Troubleshooting (cont.)
ESD - ERV Fault (DXM Only)	X	X	ERV unit has fault	Troubleshoot ERV unit fault
Green Status LED Code 3			(Rooftop units only)
No Fault Code Shown	X	X	No compressor operation	See 'Only Fan Operates'
	X	X	Compressor overload	Check and replace if necessary
	X	X	Control board	Reset power and check operation
	X	X	Dirty air filter	Check and clean air filte r
	X	X	Unit in 'Test Mode'	Reset power or wait 20 minutes for auto exit
Unit Short Cycles	X	X	Unit selection	Unit may be oversized for space - check sizing for actual
				load of space
	X	X	Compressor overload	Check and replace if necessary
	X	X	Thermostat position	Insure thermostat set for heating or cooling operation
	X	X	Unit locked out	Check for lockout codes - reset power
Only Fan Runs
	X	X	Compressor overload	Check compressor overload - replace if necessary
	X	X	Thermostat wiring	Check thermostat wiring at DXM2 - put in Test Mode and
				jumper Y1 and R to give call for compressor

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