Guide to Installing & Using a


Thought you might appreciate a few thoughts on key issues in installing and maintaining a hot water circulator pump in such a way to increase its life expectancy and extend its period of trouble free operation.

  • Fluid Direction

    All pumps have a flow direction.. make sure you have the water going through the pump in the right direction
  • Orientation

    Most of the pumps, or at least all the ones I have used must be installed with the motor shaft in the horizontal position. Read the fine print in the literature that comes with your circulator.
  • Location:

    Do not install the pump at the lowest point in your system or the crud and sediment that accumulates there will shorten the life of your hot water circulator pump.
  • Oxygen + Cast Iron = Rust

    If you install an air vent at the high point of the system and special spirovents inline to remove dissolved oxygen in the water the pumps will be less inclined to rust. Remember oxygen is an essential ingredient of rust. If its not there rust can't form.
  • Cleanliness of Boiler Fluid:

    Anything that might foul your boiler water will act as an abrasive to the internal workings of a traditional hot water circulator. Pumps have a moving impeller mounted on bearings for smooth and quiet operation.

    Metal residues from boiler fabrication, rust, solder, chemicals and/or tape introduced during construction and lime scale developed during operation all contribute to bearing wear. If you get rid of the contaminants you get rid of the abrasive wear.

  • Grounding of Electrical Supply

    Pumps come with a grounding wire to reduce the risk of electric shock. It is important that it is connected to a properly grounded receptacle in inline with your local Electrical Code requirements.
  • Trapped Air

    Air caught in the plumbing lines can create a lot of noise. Turning your circulator on and off 4 of 5 times might help in breaking the air lock.
  • Safety Relief Valve

    Installation of a safety relief valve within your outdoor boilers plumbing system will remove the risk of excessive heat or pressure build-up that could damage your pumps.
  • Flushing Your System

    After construction it is key to first flush your outdoor boiler with cold water to remove any loose particles from boiler and any plumbing that is hooked up to it.

    This can be followed by chemical cleaning to remove any residual oil and grease, just be sure to dispose of the dirty water in an environmentally sound way. Then treat your boiler water with corrosion and scale inhibitors to maintain clean water with no buildup on the interior walls. The cleaner your water the less wear and tear you will have on your small circulator pumps. See our section on water chemistry.

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