MIURA's exclusive "low water content watertube" boiler design allows the production of steam in just 10 minutes, while maintaining an 85% fuel-to-steam efficiency. The MIURA WX Gas/Low NOx Series High or Low Pressure Steam Boiler design consists of rows of vertical tubes sandwiched between two annular headers. Both headers are encased in a castable refractory with only the tubes exposed to flame and/or combustion gases. The upper header is attached to the lower header only by the tubes; as the tubes expand and contract, the headers float up and down accordingly. This floating header concept greatly reduces stress and allows for the use of cold feedwater without the fear of significant thermal shock. Any leaky tube problems have been eliminated. MIURA Boiler Inc.