Carrier Comprehensive 58MCA Specifications and Product Data for Efficient Furnace Service

LED CODE		SERVICE
		STATUS
CONTINUOUS OFF - Check for 115VAC at L1 and L2, and 24VAC at
CONTINUOUS ON -	SEC-1 and SEC-2.
	Control has 24V power.

RAPID FLASHING - Line voltage (115V) polarity reversed. If twinned, refer to twinning kit instructions.

EACH OF THE FOLLOWING STATUS CODES IS A TWO DIGIT NUMBER WITH THE FIRST DIGIT DETERMINED BY THE NUMBER OF SHORT FLASHES AND THE SECOND DIGIT BY THE NUMBER OF LONG FLASHES.

11NO PREVIOUS CODE - Stored status codes are erased when power (115V or 24V) to control is interrupted or 48 hours after each fault is cleared.

12BLOWER ON AFTER POWER UP (115V or 24V) - Blower runs for 90 seconds, if unit is powered up during a call for heat (R-W closed).

13LIMIT OR FLAME ROLL-OUT SWITCH LOCKOUT - Auto reset after three hours. For flame roll-out switch or fuse link, refer to #33.

14IGNITION LOCKOUT - Control will auto-reset after three hours. Refer to #34.

21GAS HEATING LOCKOUT - Control will NOT auto reset.

Check for: - Stuck gas valve relay on control or miswire to gas valve circuit.

22ABNORMAL FLAME-PROVING SIGNAL - Flame is proved while gas valve is de-energized. Inducer will run until fault is cleared. Check for:

- Stuck-open gas valve or leaky gas valve.

23PRESSURE SWITCH DID NOT OPEN Check for:

- Obstructed pressure tubing.	- Defective pressure switch
	(stuck closed).

24 SECONDARY VOLTAGE FUSE IS OPEN

Check for: - Short circuit in secondary voltage (24V) wiring.

31PRESSURE, DRAFT SAFEGUARD, AUXILIARY-LIMIT (when used), OR

BLOCKED VENT SHUTOFF (when used) SWITCH DID NOT CLOSE OR

REOPENED - If open longer than five minutes, inducer shuts off for 15 minutes before retry. Check for:

- Proper vent sizing and condensate pitch	- Inadequate Combustion air supply.
or sag.	- Low inducer voltage.
- Vent restriction or high winds.	- Disconnected or obstructed
- Defective inducer motor or start capacitor.	pressure tubing.

- Defective pressure switch or connections. If it opens after trial for ignition period, blower will come on for 90 second recycle delay.

33 LIMIT OR FLAME ROLL-OUT SWITCH IS OPEN - If open longer than three

minutes,code changes to #13. Check for:
- Defective blower motor or start capacitor.	- Dirty filter or restricted duct system.
- Loose blower wheel.	- Defective switch or connections.

-Inadequate Combustion air supply Flame Roll-out Switch or fuse link.

-Open Flame Roll-out switch,or fuse link. Manual reset or replace.

34IGNITION PROVING FAILURE - Control will try three more times before a lockout #14 occurs. If flame signal lost after trial for ignition period, blower will

come on for 90 second recycle delay. Check for:

-Oxide buildup on flame sensor (clean with fine sandpaper).

-Proper flame sense microamps (.5 microamps D.C. minimum).

-Gas valve turned off. - Manual shut-off valve. - Low inlet gas pressure.

-Green wire MUST be connected to furnace sheet metal.

-Inadequate flame carryover or rough ignition.

COMPONENT TEST

To initiate the component test sequence,shut OFF the room thermostat or disconnect the "R" thermostat lead. Briefly short the TEST terminal to the 'Com 24V' terminal. Status LED will flash code and then turn ON the inducer motor. The inducer motor will run for the entire component test. The hot surface ignitor, blower motor-heat speed, and blower motor-cool speed will be turned ON for 10-15 seconds each.

9	6	3
8	5	2
7	4	1

STATUS

→

TEST	HUM	Com W	Y	R	G
		24V		320615-102 REV. H

A96263

Fig. 17ÐService Label

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