Cofi Ignition transformer TRW1P4ER

Cofi TRW1P4ER is an electronic high-frequency ignition transformer with grounded pole, designed for gas and liquid fuel burners and certified to European standards. It operates on 220–240 V, 50–60 Hz, consumes 7 W, and uses capacitive discharge technology to generate a 15 kV secondary voltage at 5 mA (5 mJ ignition energy). The unit has epoxy filling and epoxy resin winding insulation, plus a silicone ignition cable. It is intended to operate only during the ignition phase, with a 100% duty cycle at ambient temperatures up to 60 °C. Net weight is 0.105 kg, gross 0.14 kg, and dimensions are 170 x 90 x 55 mm.

When replacing an ignition transformer of this type, check that the primary voltage matches the appliance supply (230 V is common, but 110 V and 24 V also exist) and that the secondary voltage and current are sufficient for the electrode gap and fuel. The duty cycle must suit the burner control (intermittent operation is typical, with a few seconds per start). Mounting arrangement, terminal pattern, and mechanical dimensions must match the existing installation to avoid modifications. The high-voltage cable must be silicone-insulated to withstand heat and voltage stress.

When ignition fails, a cracked or hardened ignition cable can leak the spark to earth, making the transformer appear faulty. Always inspect the cable before replacing the transformer.