Blast tubes & combustion heads

The blast tube, sometimes called the combustion head, is the forward section of the burner that protrudes into the combustion chamber. It channels the air-fuel mixture toward the flame front, positions the ignition electrodes, and in many designs carries the flame disc or turbulator that stabilises combustion. The geometry of this component directly affects flame shape, combustion efficiency, and emissions.

Selecting the correct blast tube requires matching several parameters: outer diameter and insertion depth to the boiler's combustion chamber opening, flange drilling pattern and any locating spigot, material specification for the expected flame temperature, and the electrode positioning if the head is supplied complete. Where a manufacturer's part number is available from the original appliance or service manual, it can be used to identify the matching item in this section. Parts from ACV, Kromschroder, and Master are represented here, and ceramic tube variants are listed in the dedicated subsection.