Technical Specifications
The Astro Series Three Speed Wet Rotor Circulators have a flow range of 0 to 20 USgpm (0 to 1.26 L/s) and a head range of 0 to 22 ft (0 to 6.7 m). They operate with a 2-pole, 115 V, single-phase, 60 Hz motor. The maximum fluid temperature is 230°F (110°C), and the maximum working pressure is 140 psi (965 kPa).

Materials of Construction
The pump body is made of cast iron for closed systems and bronze for open systems. The impeller is constructed from glass-filled polypropylene, the shaft from stainless steel, and the bearings from graphite. The gasket material is EPDM.

Dimensions and Weights
The Astro 30B-3 and Astro 50B-3 models have identical dimensions with a flange connection type and weigh 7.0 lbs (3.2 kg) and 7.4 lbs (3.4 kg) respectively. The cast iron models, Astro 30-3 and Astro 50-3, weigh 6.5 lbs (2.9 kg) and 6.8 lbs (3.1 kg) respectively.

Typical Specifications
The Armstrong three-speed selectable circulating pump models Astro 30-3 and Astro 50-3 feature a bronze/cast iron body and a polypropylene impeller. They are cULus listed and operate at 115 V/single phase/60 Hz.

Motor Data
The Astro 30-3 model has a nominal amp draw of 0.68 A at speed 3, 0.58 A at speed 2, and 0.40 A at speed 1, with a power rating of 1/25 hp. The Astro 50-3 model has a nominal amp draw of 0.90 A at speed 3, 0.76 A at speed 2, and 0.52 A at speed 1, with a power rating of 1/20 hp.

Performance and Recommendations
It is recommended to keep the operating temperature of the fluid for open systems below 150°F (65°C) to prevent calcium precipitation. The Astro Series circulators are designed for quiet operation and are suitable for residential, office, commercial, hospital, or educational institutions. They are maintenance-free, include an integral manual air vent, and come with a 2-year warranty. These models can replace most competitive water-lubricated pumps up to 1/20 hp.

Contact Information
For more information, visit Armstrong's website or contact their offices in Canada, the USA, or the UK.