Bryant 580F operation manual G. EconoMi$erIV Troubleshooting Completion, Heating Service Analysis

G. EconoMi$erIV Troubleshooting Completion

This procedure is used to return the EconoMi$erIV to opera- tion. No troubleshooting or testing is done by performing the following procedure.

1.Disconnect power at TR and TR1.

2.Set enthalpy potentiometer to previous setting.

3.Set DCV maximum position potentiometer to previ- ous setting.

4.Set minimum position, DCV set point, and exhaust potentiometers to previous settings.

5.Remove 620-ohm resistor from terminals SR and +.

6.Remove 1.2 kilo-ohm checkout resistor from terminals SO and +. If used, reconnect sensor from terminals SO and +.

7.Remove jumper from TR to N.

8.Remove jumper from TR to 1.

9.Remove 5.6 kilo-ohm resistor from T and T1. Recon- nect wires at T and T1.

10.Remove jumper from P to P1. Reconnect device at P and P1.

11.Apply power (24 vac) to terminals TR and TR1.

Table 26 — Perfect Humidity™ Dehumidification Subcooler Service Analysis

PROBLEM	CAUSE		REMEDY
Subcooler Will Not Energize	No power to subcooler control transformer.	Check power source. Ensure all wire connections
		are tight.
	No power from subcooler control transformer to liq-	1. Fuse open; check fuse. Ensure continuity of wiring.
	uid line three-way valve.	2.	Subcooler control low-pressure switch open.
			Cycle unit off and allow low-pressure switch
			to reset. Replace switch if it will not close.
		3.	Transformer bad; check transformer.
	Liquid line three-way valve will not operate.	1.	Solenoid coil defective; replace.
		2.	Solenoid valve stuck closed; replace.
Subcooler Will Not Deenergize	Liquid Line three-way valve will not close.	Valve is stuck open; replace.
Low System Capacity	Low refrigerant charge or frosted coil.	1.	Check charge amount. See system charging
			section.
		2.	Evaporator coil frosted; check and replace
			subcooler control low-pressure switch if necessary.

Table 27 — Heating Service Analysis

PROBLEM	CAUSE	REMEDY
Burners Will Not	Misaligned spark electrodes.	Check flame ignition and sensor electrode positioning.
Ignite.		Adjust as needed.
	No gas at main burners.	Check gas line for air; purge as necessary. After purging
		gas line of air, allow gas to dissipate for at least 5 minutes
		before attempting to relight unit.
		Check gas valve.
	Water in gas line.	Drain water and install drip leg to trap water.
	No power to furnace.	Check power supply, fuses, wiring, and circuit breaker.
	No 24 v power supply to control circuit.	Check transformer. Transformers with internal overcurrent
		protection require a cool-down period before resetting.
		Check 24-v circuit breaker; reset if necessary.
	Miswired or loose connections.	Check all wiring and wire nut connections.
	Burned-out heat anticipator in thermostat.	Replace thermostat.
	Broken thermostat wires.	Run continuity check. Replace wires if necessary.
Inadequate Heating.	Dirty air filter.	Clean or replace filter as necessary.
	Gas input to unit too low.	Check gas pressure at manifold. Clock gas meter for
		input. If too low, increase manifold pressure or replace
		with correct orifices.
	Unit undersized for application.	Replace with proper unit or add additional unit.
	Restricted airflow.	Clean filter, replace filter, or remove any restrictions.
	Blower speed too low.	Install alternate motor, if applicable, or adjust pulley to
		increase fan speed.
	Limit switch cycles main burners.	Check rotation of blower, thermostat heat anticipator
		settings, and temperature rise of unit. Adjust as needed.
	Too much outdoor air.	Adjust minimum position.
		Check economizer operation.
Poor Flame	Incomplete combustion (lack of combustion air)	Check all screws around flue outlets and burner
Characteristics.	results in:	compartment. Tighten as necessary.
	Aldehyde odors, CO, sooting flame, or floating flame.	Cracked heat exchanger.
		Overfired unit — reduce input, change orifices, or adjust
		gas line or manifold pressure.
		Check vent for restriction. Clean as necessary.
		Check orifice to burner alignment.
Burners Will Not Turn	Unit is locked into Heating mode for a one minute	Wait until mandatory one minute time period has
Off.	minimum.	elapsed or power to unit.

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