The model of this product is WNS4-1.25-Y (Q), which is a horizontal internal-combustion oil (gas) quick-fit boiler with a wet-back structure. The corrugated furnace liner and reburning chamber are the first return, the second and third return are threaded smoke tubes, and the upper part of the boiler is equipped with an energy saver. The boiler is equipped with complete automatic control device and safety protection device with high and low water level alarm and low water level interlock protection functions; Automatic boiler ignition, automatic burner fire regulation and flameout protection ensure the safe operation of the boiler.

The design fuel of the product is light oil or natural gas; The fuel is ejected from the burner, ignited by the electronic igniter, and combusted at a slight positive pressure in the furnace liner. The burnt high temperature flue gas enters the second and third return spiral smoke tubes by turning 180 ° from the combustion chamber, and enters the economizer by turning 180 ° from the upper part of the rear smoke box for heat exchange, and then is discharged into the atmosphere through the chimney.