Armstrong’s innovative Design Envelope 4322 Tango pump range represents a comprehensive, energy-efficient solution for heating, cooling and plumbing systems. The intelligent pump range integrates system-based hydraulics, motive power and variable speed control to create a pump solution to match any HVAC challenge.

The basis of the Design Envelope pumping systems are integrated variable speed drives (VSDs) that enable demand-based operation. This reduces pumping costs by only consuming the energy required, based on system demand at that specific time. Design Envelope pumps are specially designed with an optimized impeller size and speed control for energy efficient operation within a specific performance envelope (hence the name).

Source: Armstrong Fluid Technology

These performance envelopes are specifically selected for the best pump efficiency based on where variable flow systems operate most often. This ensures the pumping system consumes as little energy as possible and meets or exceeds ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning Engineers) 90.1 guidelines, which requires 70% energy savings at 50% of peak load.

Equipped with Armstrong’s patented “Sensorless” tech­nology, Design Envelope pumps do not require an external sensor to monitor and control system load. Sensorless pre-programs the pump’s performance data (power draw and rpm) and operating curve into the controller.

During operation, the controller monitors the power draw and rpm of the pump and determines the hydraulic performance and position of the pump’s head-to-flow condition relative to system requirements. As system changes occur (such as valves opening or closing), Sensorless will automatically adjust the pump speed to match the new pressure and flow requirements.

The Design Envelope 4322 Tango consists of a two-pump, pipe-mounted unit with integrated intelligent controls. Capable of parallel pumping or full redundancy operation, the unit can achieve up to 75% energy savings over conventional fixed speed or variable frequency operated pump installations. The 4322 Tango comes in ductile iron e-coated casing, stainless steel impeller and sintered silicon carbide mechanical seal.

The Tango can achieve a maximum flow of up to 56 L/s (900 US GPM) in parallel flow and 48 m (160 ft) head with a maximum temperature of 150° C (300° F). The pumps are available in a power range of 0.25 kW to 7.5 kW (0.33 hp to 10 hp) with sizes from 25 mm to 80 mm (1 in to 3 in). For applications requiring more than 7.5 kW, the Armstrong dual arm pump can be used and provides up to 75 kW (100 hp) of power.