Carrier 58MVP instruction manual Troubleshooting Guide

58MVP Variable-Speed 2-Stage Electronic Condensing Furnace

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Troubleshooting Guide

NOTE: Read the entire instruction manual before starting the installation.

SAFETY CONSIDERATIONS
INDEX
	PAGE
Instructions	1
Example	2
Sequence of Operation	1-5
Self-Test Mode	2
Heating Mode	2
Heating Mode-Two Stage	2
Emergency Heat Mode	2-3
Cooling Mode	3
Heat Pump Mode	3-4
Continuous Fan Mode	4
Component Test	4-5
Bypass Humidifier Mode	5
Dehumidification Mode	5
Zone Mode	5
Start Here	6
Service Label/Fault Code Instructions	7-8
Improper Operation With No Flashing Fault Code	9
Not Enough Cooling Airflow	10
High-Fire Temperature Rise Too Low (Cold Blow)	11
LEDs 1, 2, 3, or 4 On Solid	11-12
RED LED2 Flashing	12
Fault Code 11ÐNo Fault in Recent History Display	13
Fault Code 12ÐBlower Calibration Lockout	13-15
Fault Code 13ÐLimit Switch Lockout	15-16
Fault Code 14ÐIgnition Lockout	17
Fault Code 21ÐInvalid Model Selection	17
Fault Code 22ÐSet Up Error	18
Fault Code 23ÐInvalid Blower Airflow Selection	18
Fault Code 24ÐSecondary Voltage Fuse Is Open	19-20
Fault Code 31ÐHigh-Pressure Switch Fault	21-22
Fault Code 32ÐLow-Pressure Switch Fault	23-24
Fault Code 33ÐLimit Switch Fault	24-25
Fault Code 34ÐIgnition Proving Fault	26-27
Fault Code 41ÐBlower Outside Valid Speed Range	27-28
Fault Code 42ÐInducer Outside Valid Speed Range	29-30
Fault Code 43ÐPressure Switch Calibration Fault	30-31
Fault Code 44ÐBlower Calibration Fault	32
Cleanup and Start-Up Instructions	33
APPENDIX AÐBoard Layout & Wiring Schematic	34-35
APPENDIX BÐIsolation Circuits	36
APPENDIX CÐPressure Check Diagram	36
APPENDIX DÐQuick Motor Test Procedure	37-39
APPENDIX EÐVariable-Speed Condensing Furnace Duct Static
and Blower Operation	40-44
APPENDIX FÐQuick Reference Information	45
APPENDIX GÐThermostat Staging Algorithm	46-47

INSTRUCTIONS

This guide uses your expertise and observations to lead you to the trouble spot as efficiently as possible. This is only intended as a guide and should not be used blindly. Your experience and expertise are of high value when troubleshooting this unit. Do not disregard all of your instincts.

The microprocessor furnace control was designed with diagnostic capabilities built in. LEDs are used to flash a fault code which will lead you to 1 of the subsections as listed in the Index.

You should ALWAYS begin in the START HERE subsection (see Index for page number) which will guide you to the appropriate subsection where a minimal number of steps will be used to correct the problem. If you are very experienced at how this furnace operates and you suspect the problem is either the blower motor, inducer motor, or furnace control board, you can use the quick motor test procedure at the end of the troubleshooting guide to isolate the problem or direct you to appropriate section in main troubleshooting guide.

Once in a subsection, read the statement or question. A statement will have a number in the "GO TO" column. Do whatever the statement says, then proceed to step indicated in the "GO TO" column.

If the step is a question (a question will have a number in the "YES" or "NO" column), answer it "YES" or "NO." If the answer is "YES," go to step indicated in "YES" column. If the answer is "NO," go to step indicated in "NO" column.

Let's try our guide out using the EXAMPLE section below, and see how it works. Suppose that the problem is a defective low-pressure switch (for example will not make). This is an internal problem and cannot simply be seen. We go to the START HERE section to Step 1.

Additional Service Tools are available for current variable speed condensing furnaces. The Advanced Product Monitor Kit KGAFP0101APM includes a harness and diskette that allows communication with the control board through a personal com- puter (RS-485 adapter required). The ICM Motor Simulator Kit KGASD0101FMS is a plug-in device to help trooubleshoot ICM inducer and blower motors and control boards. Reference price pages for current kit numbers.

SEQUENCE OF OPERATION

Furnace control must be grounded for proper operation, or control will lock out. Control is grounded through green wire routed to gas valve and burner box screw.

Using schematic diagram (see Appendix A), follow sequence of operation through different modes. This furnace has a new control system. Read and follow wiring diagram carefully.

NOTE: If 115-v power supply to furnace or blower access panel switch is interrupted during a call for heat, blower operates at low-heat speed for 60 sec when power is restored before heating cycle is resumed.

Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.

Book	1	4	PC 101	Catalog No. 535-754	Printed in U.S.A.	Form 58MVP-8SM	Pg 1	9-99	Replaces: 58MVP-6SM
Tab	6a	8a