The YY(Q)W(L) series horizontal&vertical type gas-fired/oil-fired thermal oil boilers adopt a three-pass circular coil structure. The coil ends are tapered, effectively protecting the furnace walls at the boiler ends. Equipped with advanced combustion devices, the boiler operates fully automatically. After the fuel is ignited by the burner, the resulting flare fills the circular coil and transfers radiant heat through the coil walls—this is the first pass. The high-temperature flue gas generated by combustion converges at the rear furnace door and then turns to enter the second pass, the convection tube bundle region. After convection heat exchange, the flue gas temperature gradually decreases before reaching the front furnace door, where it turns again to enter the third pass tube bundle region. Finally, it passes through the economizer and enters the chimney to be discharged into the atmosphere.
