NORTEC WB burners are designed in 2 frames of typical sizes (see section 4).
Models WB60/120 (pic. 1) have one line to connect compressed air and one pressure regulator.
Models WB 230/270 (pic. 2) have two lines to connect compressed air and two pressure
regulators what follows the principle of two-stages start.
Pic. 1 Burners NORTEC WB60 and WB 120
Pic. 2 Burners NORTEC WB230 and WB270