Circulator Pumps

Aurora

I recently installed a Nibco Panel purchased from Menards.  It uses a Grundfos circulator pump. I started the system up and let it run for about an hour.  Being a novice to the radiant heat scene I wasn't sure how hot the pump should feel to the touch so I shut the system down and am looking for answers.

Question:  In general  how hot should the pump itself be to the touch when operating? 



PS: I do understand that there is hot liquid running through the pump at the time but in general is there a rule the pump should be the temp of the supply from the boiler plus anything or should it not be that hot...



Thank you

Gordy

Depends

How long it runs, and everyone has a different perception on what feels warm to the touch.



In general if the system is purged of air, and your sure of that. Then if the circ has been running for a long period of time getting the system up to temp then yes it will get warm to the touch. Not so much you can't leave your hand on it though.

SWEI

fractional horsepower conventional circulators

use motors that are only about 50% efficient.  Lots of heat.  An ECM will run quite a bit cooler.

Aurora

Thank you

for your help!