Rheem Furnace Error Code 58: Causes, Diagnosis, and Repair Steps

Rheem Furnace Error Code 58 usually indicates a fault related to the furnace safety or air-flow control systems, but the exact meaning can vary by model. This article explains common interpretations of Code 58, step-by-step diagnostics, likely causes, DIY checks, repair options, parts and cost guidance, and safety recommendations for U.S. homeowners and technicians.

Item	Summary
Common Causes	Blocked filter, clogged vent/condensate, faulty pressure switch, inducer motor issues, limit switch or control board anomalies
Severity	Ranges from low (maintenance) to high (gas safety / ignition lockout)
DIY Checks	Reset power, check filter, inspect vents, look for error blink patterns, verify pressure tubing
When To Call Pro	Suspected gas valve, wiring faults, failed control board, persistent lockouts, or if uncomfortable with gas/electrical work

What Rheem Furnace Code 58 Typically Means

Rheem furnace codes are model-specific, so Code 58 can represent related issues across safety and airflow subsystems rather than a single component failure. In many Rheem and Ruud control documents, Code 58 is associated with problems in the pressure switch, inducer motor performance, or high-limit conditions that prevent normal ignition to protect against unsafe combustion or poor venting.

Important: Always consult the furnace’s model-specific service manual or the LED blink sequence printed on the unit for the exact definition before replacing parts.

How The Furnace Diagnostic System Works

Modern furnaces use a control board that monitors sensors: the pressure switch verifies inducer operation and vent integrity, the high-limit switch checks heat exchanger temperature, the flame sensor confirms ignition, and the inducer motor ensures exhaust flow. When a monitored parameter stays outside expected ranges, the board registers an error code such as 58 and prevents further operation for safety.

Initial Safety Steps And Quick Checks

Before touching the furnace, turn off electrical power at the service switch or breaker and shut off the gas if a leak or smell is suspected.

• Record the LED blink or code display pattern: this helps technicians identify intermittent vs. persistent faults.
• Reset power for 30 seconds to clear transient lockouts; if the code returns, deeper diagnosis is required.
• Check the air filter and replace if dirty; restricted airflow can trigger limit-related faults.

Common Causes Of Code 58 And How To Inspect Them

1. Dirty Or Blocked Air Filter

Restricted airflow raises heat exchanger temperatures and can trip limit switches. Inspect the filter and replace with the correct MERV rating if clogged. This is one of the simplest and most common fixes.

2. Blocked Intake Or Exhaust Vents

Outdoor intake or exhaust termination can be blocked by debris, bird nests, snow, or nearby vegetation. Visual inspection and clearing of vents often resolves pressure-related faults.

3. Condensate Trap Or Drain Clogs (High-Efficiency Furnaces)

Condensing furnaces rely on condensate drains; clogs can cause safety switches or float sensors to react. Inspect the trap and drain line, clear blockages, and verify proper condensate removal.

4. Faulty Or Stuck Pressure Switch

The pressure switch senses inducer-created vacuum. Check the pressure tubing for cracks or disconnects and confirm the switch opens/closes with inducer operation. A failing switch or collapsed tubing commonly causes Code 58-like indications.

5. Inducer Motor Or Fan Issues

If the inducer fails to start, runs weakly, or has worn bearings, the control board will detect insufficient airflow and register faults. Listen for unusual noises and verify the inducer runs during the start sequence.

6. High Limit Or Overheat Condition

A tripped high-limit switch indicates overheating due to blocked airflow, closed registers, or a failing blower. Verify return vents and supply registers are open and blower function is normal.

7. Control Board, Wiring, Or Sensor Faults

Intermittent wiring, corroded connectors, or a malfunctioning control board can present as Code 58. Inspect connectors for corrosion and burns; check wiring continuity where safe.

Step-By-Step Diagnostic Procedure

1. Power Cycle: Turn off power 30 seconds and restart. Note if Code 58 clears or returns.
2. Visual Inspection: Check vents, filter, condensate line, and visible wiring for obvious issues.
3. Listen And Observe: Start the furnace and watch the ignition sequence. Confirm inducer runs, pressure switch closes, and ignitor/flame appears.
4. Pressure Tubing: Inspect and replace brittle or collapsed tubing between inducer and pressure switch.
5. Verify Pressure Switch Operation: Using a multimeter and manufacturer test points, confirm the switch changes state during inducer startup. Follow model manual for safe test procedure.
6. Test Inducer Motor: Measure voltage at the inducer while running; abnormal current or slow spin indicates motor replacement.
7. Check Limit Switch: Test with a multimeter for continuity when cool; replace if open when it should be closed.
8. Scan Error History: Some Rheem models retain logs. Use the manual to interpret advanced diagnostics.

DIY Repairs Versus Professional Service

Simple tasks like filter replacement, clearing vents, and checking visible tubing are appropriate for homeowners. However, any work involving gas valves, internal wiring, control board replacement, or in-depth electrical testing should be performed by a licensed HVAC technician to avoid safety risks and voiding warranties.

When To Call A Pro: persistent Code 58 after basic checks, suspected gas leaks, failed inducer motor, control board faults, or inability to safely test components.

Estimated Parts And Repair Costs

Repair Item	Typical Range (US)
Air Filter Replacement	$10–$60
Pressure Tubing Replacement	$10–$35
Pressure Switch	$40–$150
Inducer Motor	$150–$450
Limit Switch	$20–$80
Control Board Replacement	$200–$700+
Labor	$75–$200+ Per Hour

Prices vary by region, brand, model, and the complexity of the repair. Always get multiple estimates for major replacements.

Preventive Maintenance To Avoid Future Code 58 Events

• Replace or clean the air filter every 1–3 months depending on use and filter type.
• Schedule annual furnace tune-ups with a licensed HVAC contractor focusing on inducer performance, sensor calibration, and safety controls.
• Keep outdoor vents clear of debris and maintain 2–3 feet of clearance around intake and exhaust terminations.
• Ensure proper condensate drainage for high-efficiency units, and periodically flush trap/drain lines.
• Inspect and replace brittle pressure tubing during routine service to prevent vacuum leaks.

Safety Tips And Regulatory Notes

Working with gas appliances carries risks. Carbon monoxide, gas leaks, and improper repairs can endanger occupants. Follow local codes and manufacturer recommendations, and ensure technicians are NATE-certified where applicable.

CO Alarm Placement: Install and test carbon monoxide detectors near sleeping areas and following manufacturer guidelines whenever a gas furnace is present.

What To Tell A Technician When Calling For Service

• Exact furnace model and serial number.
• The displayed Code 58 and any other LED codes or blink patterns recorded.
• Actions already taken (filter changes, reset attempts, visual checks).
• Any unusual sounds, smells (gas or burning), or intermittent behavior noticed.

Model-Specific Reference And Documentation

Because code definitions can vary by control board and model series, the furnace’s service manual or the label inside the access panel provides the authoritative error-code list. Homeowners should photograph the label and code display and provide it to the technician for faster diagnosis.

Key Takeaways

Rheem Furnace Error Code 58 is frequently related to pressure-switch/inducer performance, airflow restrictions, or limit safety trips. Start with safe, basic checks: replace filters, clear vents, and record the LED error pattern. If the fault persists or involves gas/electrical components, contact a licensed HVAC technician to diagnose and repair the issue safely.