The Allanson 421-BT290 is an OEM ferromagnetic ignition transformer designed to provide reliable high-voltage spark energy for a wide range of oil burner and multi-burner HVAC applications. It runs on a 120 VAC primary and steps up to a 10,000 VAC secondary output at ~250 VA and ~23 mA, making it suitable for constant-duty ignition use. Its robust design features high-temperature wiring, midpoint grounding, and compliance with EMI/RFI noise suppression standards for quieter, safer operation. This model is a universal replacement transformer and is commonly cross-referenced to legacy parts like Webster 312-24AB0202, Dongan A10-SQ10, and France LGDV.
Key Features
- 120 VAC primary voltage — standard line input for ignition circuits
- 10,000 VAC secondary output for consistent ignition spark energy
- ~250 VA rated output (~23 mA) for robust performance in burner systems
- Ferromagnetic double-pole design for constant-duty operation
- Midpoint-grounded core improves electrical stability and safety
- High-temperature internal wiring for durability in heat-intensive environments
- Universal service replacement unit — works with many burner manufacturer cross references like Webster, Dongan, and France (e.g., Webster 312-24AB0202)
