ICMA draught regulator 147 / 90147AE06

This flue regulator is a mechanical thermostatic device designed for solid fuel boilers. It automatically adjusts the combustion air damper through a chain, maintaining the boiler water temperature within a range of +30°C to +90°C. It operates without electricity and is made of nickel-plated brass, with a G 3/4" male tapered thread. The unit is suitable for ambient temperatures from 30°C to 120°C and includes a chain of approximately 1.2 m. It is intended for boilers burning wood, coal, briquettes, or pellets.

Mechanical thermostatic draft regulators are selected by matching the connection thread to the boiler tapping, the temperature adjustment range to the system requirements, and the chain length to the distance between the regulator and the air damper. The device is screwed into a threaded hole on the boiler or flue, and the chain is attached to the damper lever. Such regulators can be mounted horizontally or vertically, depending on the boiler design. Before ordering, confirm the thread type and size (commonly G 3/4" male tapered) and check the available adjustment range for compatibility.

When a draft regulator fails, boiler temperature becomes difficult to control: the system may overheat and shut down on limit switches, or fail to reach operating temperature. Water temperature may swing between extremes as the thermostatic element loses sensitivity or the damper mechanism jams. Inspect the chain for corrosion or kinks, check that the damper moves freely, and verify the thermosensitive element responds to temperature changes by hand-testing the regulator outside the boiler before replacement.