An extremely economical 25kW heating-only boiler with a low ErP With an A rating, the Alpha E-Tec 25R Regular is a handy addition to the typical family house because it can be used in conjunction with a storage cylinder to provide an ample supply of hot water. The E-Tec 25R is a lightweight, small unit that fits nicely into kitchen or utility cabinets. It can be used as part of a kit in an Alpha sealed system or in open-vented systems. Daily use and maintenance are made easier by an easily accessible NTC and a lighted display.