Armstrong Design Envelope pumps are a complete solution for heating, cooling and plumbing systems. The integration of a perfectly matched pump, motor and intelligent variable speed controller creates the highest value pumping solution. Through design advances, Armstrong has eliminated the cost trade-offs that are frequently attached to sustainable choices. Design Envelope offers the lowest installed cost and the lowest life cost of any pumping solution today. Design Envelope solutions reduce pumping costs through variable speed, demand-based operation — consuming only the energy required, based on current system demand. Design Envelope pumps use a combination of optimised impeller size and speed control for energy efficient operation within a given performance envelope. The performance envelopes are mapped for the best pump efficiency, where variable flow systems operate most often. This ensures a building’s hydronic pumping system consumes as little energy as possible. Design Envelope pumps up to 7.5 kW exceed this legislation and are ie5 certified