AllansonIgnition Transformers

Allanson 421-557 Ferromagnetic Ignition Transformer for Arco American Standard

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-03293

Also listed as: 421557 · 421 557

Brand

Allanson

Item

421-557 Ferromagnetic Ignition Transformer for Arco American Standard

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

ARCO AMERICAN STANDARD 

Hv Terminal

Buss Bar Clips 

Junction Box

EXTERNAL 

Input Voltage

120V 

Input Frequency

60Hz 

Secondary Voltage

10000V 

Burner Manufacturer

ARCO AMERICAN STANDARD 

Datasheet Content

[{"filename":"FerromagneticDP_SpecSheet_21-4141121_04-Sep-2025.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                                    181 Cooper Ave., Suite 112, Tonawanda, NY 14150   #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 421-557 ignition transformer used for?

The Allanson 421-557 ferromagnetic ignition transformer is designed for constant-duty ignition in commercial, residential, and industrial oil burners. It is specifically configured for ARCO American Standard burners, providing a reliable 10,000 V secondary voltage at 23 mA to ignite fuel oil in heating systems.

What are the specifications of the Allanson 421-557?

The Allanson 421-557 is a double-pole, mid-point ground ferromagnetic transformer. It operates at 120 V input, 60 Hz, with a secondary voltage of 10,000 V RMS and a secondary short-circuit current of 23 mA. It features an external junction box and buss bar clips for the HV terminal.

Where to buy the Allanson 421-557 in Singapore?

3G Electric supplies the Allanson 421-557 ferromagnetic ignition transformer to customers in Singapore. We source and deliver this model, handling logistics, customs clearance, and local delivery. Contact 3G Electric for pricing and lead time on your order.

How to install the Allanson 421-557 ignition transformer?

Install the Allanson 421-557 by mounting it securely on the burner, connecting the external junction box to a 120 V, 60 Hz supply, and attaching the buss bar clips to the spark electrodes. Ensure the loading air gap is set between 1/8 and 3/16 inches for proper spark intensity.

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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