AllansonIgnition Transformers

Allanson 421-331 Ferromagnetic Ignition Transformer for Lennox

Allanson’s Double Pole ferromagnetic transformers are designed for constant duty and provide the most reliable ignition source for commercial, residential and industrial oil applications.

SKU 3G-OTH-03290

Also listed as: 421331 · 421 331

Brand

Allanson

Item

421-331 Ferromagnetic Ignition Transformer for Lennox

Local availability & support — Singapore

Local office: 20 Woodlands Link #09-05, Singapore 738733
Phone: +65 8878 8355
Delivery: Same-day or next-business-day delivery within Singapore for in-stock items; 7–14 days for factory-order parts from Europe.
Payment: Invoicing in SGD. PayNow, bank transfer, and corporate PO accepted.
Ships to: Singapore

Technical Specifications

Allanson

Poles

Double 

Current

23mA 

Can Size

Large Can Series 

Grounding

Mid Point Ground 

Application

OIL

Burner Type

LENNOX 

Hv Terminal

Zinc Plated Button 

Input Voltage

120V 

Hinge Location

End Hinge 

Input Frequency

60Hz 

Secondary Voltage

10000V 

Burner Manufacturer

LENNOX 

Datasheet Content

[{"filename":"FerromagneticDP_SpecSheet_21-4141121.pdf","text":"FERROMAGNETIC TRANSFORMERS\n                                                                       2721 / 2744 / 2730 / 2714 / 421 / 444 / 911 / 912\n                                                                                       SPECIFICATION GUIDE\n\n\n                    DOUBLE POLE, MID POINT GROUND MODELS\n\n Allanson’s ferromagnetic transformers are designed for constant duty and provide the most reliable ignition\n source for commercial and/or industrial oil applications.\n\n\n  Absolute Maximum Ratings\n  Model #                                           2721, 421*        2744, 444*       911*       2730, 912*         2714\n  Rated Operating Input Voltage (V)                     120               240           240           120             120\n  Operating Input Voltage Range (V)                   108-132           216-252      216-252        108-132        108-132\n  Input Supply Frequency (Hz)                            60                60           50             50             60\n  Primary Voltage - Amperes (VA)                        250               250           250           250             275\n  Secondary Voltage (RMS)                              10,000            10,000       10,000         10,000         12,000\n  Secondary Short Circuit Current (mA)                   23                23            23            23              20\n  Storage Temperature (°C)                          -40 to +80        -40 to +80    -40 to +80    -40 to +80      -40 to +80\n  Operating Temperature (°C)                        -30 to +40        -30 to +40    -30 to +40    -30 to +40      -30 to +40\n  Operating Relative Humidity (%)                        90                90            90            90              90\n  Loading Air Gap (inches)                           1/8 - 3/16        1/8 - 3/16   1/8 - 3/16     1/8 - 3/16     1/8 - 3/16\n\n * Service replacement transformers are available in select models.\n\n\n\n\n83 Commerce Valley Drive E., Markham, ON L3T 7T3                                99 Adams Blvd., Farmingdale, New York 11735    #21-414\n      T: 1.800.661.7251 ● F: 1.416.752.6718                                         T: 1.631.293.3880 ● F: 1.631.293.3470       1121\n\n\n                  For more information, please visit us at allanson.com or e-mail us at cservice@allanson.com"}]

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Allanson Products

3G Electric (S) Pte. Ltd. — Singapore

Product Description

Allanson’s Double Pole ferromagnetic transformers are designed for constant duty and provide the most reliable ignition source for commercial, residential and industrial oil applications.

Frequently Asked Questions

What is the Allanson 421-331 ignition transformer used for?

The Allanson 421-331 is a ferromagnetic ignition transformer designed for constant duty in commercial, residential, and industrial oil burner applications. It is specifically configured for Lennox burners, providing a reliable ignition source with a 10,000 V secondary voltage and 23 mA secondary short circuit current.

What are the specifications of the Allanson 421-331?

The Allanson 421-331 is a double pole, mid point ground transformer with an input voltage of 120 V at 60 Hz. It delivers a secondary voltage of 10,000 V and a secondary short circuit current of 23 mA. The operating temperature range is -30 to +40 °C, and it features a zinc plated button HV terminal.

Where to buy the Allanson 421-331 in Singapore?

You can source the Allanson 421-331 ignition transformer through 3G Electric in Singapore. We handle logistics, customs clearance, and delivery to your facility. Contact us for pricing and lead time on this Lennox-compatible replacement transformer.

How to install the Allanson 421-331 ignition transformer?

To install the Allanson 421-331, first ensure the burner is disconnected from power. Mount the transformer using the end hinge location, connect the 120 V input supply, and attach the zinc plated button HV terminal to the ignition electrode. Maintain a loading air gap of 1/8 to 3/16 inches for proper operation.

Used in

Common applications for Allanson

Oil burner retrofit maintenance — Allanson CAT 1092 TYPE F transformer replacement in existing Beckett control circuits

Industrial heating-system commissioning — Control transformer installation in multi-stage flame-safeguard burner startup sequences

Plant emergency maintenance — Same-day T92 transformer procurement to restore failed ignition control voltage supply

Burner control-cabinet assembly — Allanson transformer integration in custom control-circuit designs for process-heating applications

Field technician spare-parts kit — Stocking CAT 1092 and T92 variants for mobile maintenance coverage of regional burner installations

Allanson Products

3G Electric supplies Allanson ignition transformers. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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