Cofi Ignition transformer TRS820P/29

The Cofi TRS820P/29 is a double-pole ignition transformer designed for gas and dual-fuel burners. It operates on a 230 V, 50 Hz supply and provides a secondary voltage of 4–4 kV with a secondary current of 20 mA. The transformer has a duty cycle of ED 19% (3 minutes) and is active only during the ignition phase. Its compact dimensions are 150 mm in length, 80 mm in width, and 70 mm in height. This model is equivalent to Fida Compact SP41 8/20 PM and Orto TE084D.

When selecting a replacement ignition transformer of this type, verify that the primary voltage (e.g., 230 V) and frequency match the burner's supply. Confirm the secondary voltage and current requirements, as well as the duty cycle, to ensure compatibility with the control system. Check the mounting dimensions and terminal arrangement, including the connector pattern for the ignition cable, as these vary between models. Measure the physical space available and compare the pole configuration (e.g., double-pole) to the existing unit.

Typical failures of ignition transformers include internal short circuits or open windings, often caused by overheating or moisture ingress. Symptoms may include no spark at the electrodes, weak or intermittent sparking, or the burner failing to ignite. Before replacing the transformer, inspect the ignition cable for cracks or hardening, and check the electrode gap and condition for soot or damage, as these can mimic transformer failure.