The Carrier LH33ZS004 Hot Surface Ignitor is a critical OEM furnace replacement part engineered for precise ignition in Carrier, Bryant, Payne, and Day & Night induced combustion systems. This silicon carbide ignitor provides consistent thermal performance and serves as the direct factory authorized replacement for several legacy part numbers, including LH33ZS001, LH33ZS002, LH33ZS003, 331930-751, and 41-409. When troubleshooting a furnace that fails to fire despite receiving line voltage at the ignitor harness, a cracked or high-resistance heating element is often the culprit. The LH33ZS004 features a standard 2-pin plug for a true plug-and-play installation, minimizing downtime during emergency service calls. Measuring approximately 2" x 3", this hot surface ignitor is factory-tested to ensure reliable amperage draw and surface temperature, making it an essential stock item for technicians servicing residential gas furnaces in cold climates. Always handle with care to avoid contaminating the element with skin oils.

Key Benefits

• Direct OEM Replacement: Ensures exact fit and electrical compatibility with Carrier-brand furnace control boards and burner assemblies.
• Broad Compatibility: Supersedes multiple older part numbers including LH33ZS001A and 332505-751, reducing truck stock requirements.
• High-Temperature Durability: Constructed from robust silicon carbide designed to withstand rapid thermal cycling without premature failure.
• Simplified Serviceability: Features a pre-terminated connector for rapid field replacement without the need for wire stripping or crimping.
• Factory Verified: Each unit is pre-tested to ensure it meets strict ignition timing and resistance specifications.

Common Questions

How do I test if the Carrier LH33ZS004 is defective?
Using a multimeter, check for continuity across the pins. If the circuit is open or if there is visible white cracking on the element, the ignitor must be replaced. Also, verify the furnace control board is sending 120V to the ignitor during the startup sequence.

Can I use this ignitor in a Bryant or Payne furnace?
Yes, this is a universal OEM component across the Carrier family of brands, covering a wide range of forced-air gas furnaces.

Why did my new ignitor fail immediately after installation?
The most common cause is touching the black heating element with bare fingers. Skin oils create hot spots that cause the silicon carbide to bridge and crack. Always handle the part by its ceramic base.

Item is Non Cancelable / Non Returnable

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.