CARRIER • GOODMAN • LENNOX • RHEEM • YORK OEM REPLACEMENTS

Furnace Hot Surface Igniters & Diagnostic Hub

Authoritative engineering cold resistance benchmarks (11–17Ω for Silicon Nitride vs 40–80Ω for Carbide), control board diagnostic blink codes, and universal upgrade kits for gas furnaces that fail to ignite.

Search Igniter Fitment Matrix Resistance Diagnostic Calculator
11–17 Ω 120V Silicon Nitride
40–80 Ω 120V Silicon Carbide
Si3N4 Ceramic Non-Fragile Upgrade
CAD BLUEPRINT: UNIVERSAL SILICON NITRIDE (Si3N4) IGNITER ASSEMBLY SCALE 1:1 CALIBRATED
UNIVERSAL FLANGE CERAMIC BASE SILICON NITRIDE ELEMENT (Si3N4) • RESISTANCE: 11.0 – 17.0 Ω OPERATING TEMPERATURE: 2,200°F (1,200°C) IN 3 SECONDS
COLD RESISTANCE DIAGNOSTIC BENCHMARK

Furnace Igniter Resistance Health Check

Enter your digital multimeter cold resistance measurement (in Ohms) to instantly diagnose whether your furnace igniter is electrically healthy, suffering high-resistance fatigue, or completely broken.

PASS: COLD CONTINUITY VERIFIED
11.0 Ω – 17.0 Ω (Silicon Nitride 120V)

Nominal healthy reading for a 120V Silicon Nitride igniter. Igniter filament is intact.

OEM CROSS-REFERENCE DIRECTORY

Gas Furnace Igniter Fitment Matrix

Cross-reference major furnace manufacturers (Goodman, Carrier, Lennox, Rheem, York, Trane) with verified cold resistance benchmarks, OEM part numbers, and universal replacement links.

OEM Manufacturer Part Number Chemistry & Voltage Cold Resistance Benchmark Common Furnace Models Action
Universal Upgrade Universal 120V Silicon Nitride / 120V 11.0 – 17.0 Ω Replaces Norton 271N, 201N, White-Rodgers 768A Check Price on Amazon
Goodman / Amana 0130F00008 Silicon Nitride / 120V 11.5 – 15.0 Ω GMH, GKS, GMV, CAPF (Modern Goodman 80% & 90%+) Check Price on Amazon
Carrier / Bryant / Payne LH33ZS004 Silicon Nitride / 120V 11.0 – 16.0 Ω 58STA, 58DLA, 58MCB, 350AAV, WeatherMaker Check Price on Amazon
Lennox / Armstrong 768A-844 / 70L54 Silicon Nitride / 120V 11.5 – 16.5 Ω G40, G43, G50, G51, Elite Series Check Price on Amazon
Rheem / Ruud 62-22868-93 Silicon Nitride / 120V 11.0 – 15.5 Ω Classic 90 Plus, Criterion II, RGPH, RGLH Check Price on Amazon
HVAC ENGINEERING DIAGNOSTICS

How to Diagnose a Gas Furnace Ignition Lockout

When a gas furnace thermostat calls for heat, the control board initiates a mandatory safety sequence:

  1. Draft Inducer Blower Energizes: Creates negative draft pressure; closes the pressure switch.
  2. Igniter Warm-Up: The control board delivers 120V to the hot surface igniter for 15 to 45 seconds until it glows incandescent orange (>2,200°F).
  3. Gas Valve Opens: Natural gas or propane flows over the igniter and ignites instantly.
  4. Flame Sensor Verification: The microamp flame rod detects ionization current (1.0 to 5.0 µA). If ignition fails, the board shuts gas off after 4 seconds.

The #1 Cause of "Blower Runs but No Heat"

If the draft inducer runs, you hear a click, but the burners never light and the furnace shuts down after 3 retries (often flashing 3 blinks on the control board LED), 9 times out of 10 the hot surface igniter is cracked or burned out.

UPGRADE ADVISORY

Why You Must Upgrade Silicon Carbide to Silicon Nitride

Older furnaces used Silicon Carbide (SiC) igniters. They are extremely brittle; touching them with oily fingers or bumping them during filter changes fractures the ceramic. Their resistance increases every heating cycle until they fail to reach ignition temperature.

  • Silicon Nitride ($Si_3N_4$) Durability: Nitride igniters are dense structural ceramics virtually immune to physical shock and finger-oil contamination.
  • Rapid Heat-Up: Reaches 2,200°F in under 3 seconds with consistent 11–17Ω resistance over a 10-year lifespan.
  • Universal Compatibility: Universal bracket kits allow a single silicon nitride SKU to replace over 95% of all furnace igniters in North America.