... % Corrugated Furnace. Product Features of WNS Oil/Gas-fired Hot Water Boiler1. This horizontal wet-back boiler features ... 5. Multi-layer protection on pressures, temperature, water-level and burner itself keeps the boiler to ... widely adapted to various fuels, including light oil, heavy oil, residual oil, natural gas, coal gas, and liquefied ... , for customer’s option. WNS Oil/Gas-fired hot water Boiler