... -Back). 3.100% Corrugated Furnace. Product Features of WNS Oil/Gas-fired Hot Water Boiler1. This horizontal wet-back boiler features three-stage ... . It is widely adapted to various fuels, including light oil, heavy oil, residual oil, natural gas, coal gas, and liquefied petroleum gas;7 ... style and high pressure style, for customer’s option. WNS Oil/Gas-fired hot water Boiler