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Pump question

The basement has baseboard that runs through the main gas boiler which also gives steam. I just put in a new pump that has three speeds. What is the best and most efficient speed to run the pump for the baseboard at? The Pump is an Astro30 and the new one is an Astro 30 updated with 3 speeds


  • Most Efficient...

    Well, the obvious answer is the lowest speed that will make the space comfortable. At the highest speed, the pump will deliver more heat to the space. The quantity of heat that is introduced to the space can be determined mathematically by:

    Q (Btu/hour) = GPM (Flow rate of the pump) x 500 x TD (Temp Diff across the baseboard)

    From this, you can see that the higher the flow rate, the higher the heat output.

    Personally, I would try the medium speed first. If the space is too cool, move to the higher speed.

    Hope this helps!
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