Armstrong Circulating Pump Installation

Installing a pump can be quick and simple, especially if you have a guide to reference while getting it running. Below you can follow along with this Armstrong circulating pump installation guide that will take you from flushing the system through electrical wiring. 

The following installation guide is made for the Armstrong Astro 2 circulator models. 

Circulating Pump Installation

Before installation, it’s recommended to complete any soldering needed. This eliminates the possibility of solder dropping into the pump body. 

• Step 1 – Thoroughly flush the system out. 
• Step 2 – Check that the flow direction of the water through the pump body matches the arrows on the circulator body. 
• Step 3 – Install the circulator in either the outlet or inlet line to the boiler or hot water heater. Make sure there’s a split between the circulator body and the motor in a vertical position.
• Step 4 – Install the circulator with the terminal box above or beside the motor. If the terminal box is under the motor, remove the motor mounting screws and rotate the motor to the proper position. Make sure the gasket is seated before evenly retightening the mounting screw to 4.5 – 5.5 lb/ft (6 – 7.5 Nm).
• Step 5 – Check that the rotor spins freely by removing the plug, insert a flat head screwdriver into the slot in the end of the rotor shaft and turn. Retighten the plug to 1.5 – 2 lb/ft (2 -2.7 Nm) and ensure that no water is leaking at any sealing contacts.

Electrical Wiring

Any electrical wiring should be done by a qualified electrician and be installed following national electrical codes, local codes and regulations. 

• Step 1 – Make sure the power is disconnected before wiring the circulator. 
• Step 2 – Loosen the screws from the terminal box cover and remove the screws and cover.
• Step 3 – Install the desired strain relief into 1/2″ npt threaded access kit.
• Step 4 – Insert wires through the strain relief connector and into the terminal box.
• Step 5 – Strip 3/16” of insulation from the ends of the three wires to be connected.
• Step 6 – Insert the wires into the terminal strip, pressing down firmly on the terminal lever. Insert the stripped wire into the opening and release the lever. Tug on the wire gently to ensure it’s secured.
• Step 7 – Connect the hot wire to terminal ‘l', the neutral wire to terminal ‘n' and the ground wire to the terminal with the symbol.
• Step 8 – Tighten the terminal box cover.