How to Easily Size a Circulating Pump
- 1). Run a tape measure along all the piping and the boiler where the circulating pump will be installed. Move the tape measure back to the boiler, and mark the longest loop on the pipes between fittings. If the circulator can move through the longest loop, it will be able to move through all the others.
- 2). Inspect all the pipe where the circulating pump will be installed, and mark all the fittings -- the small pieces where two pipes meet each other. This will help determine how many gallons of water will be needed.
- 3). Refer to the manual for your particular boiler system. It will state how much BTU/hr it needs to properly operate. Note that number, and match it up with the proper circulating pump that is the correct size. For every 100,000 BTU/hr, a circulating pump must have 10 gallons of water per minute of flow rate.
- 4). Pick a circulating pump that can handle the proper amount of water output based on the size of your boiler, and refer to the manufacturer's instructions for installation procedures.