View Single Post
  #3   Report Post  
Posted to uk.d-i-y
Tony Williams
 
Posts: n/a
Default Testing a central heating pump

In article ,
Set Square wrote:
Most pumps seem to come with dire warnings about not running them
dry.
Anyone know why this is? Does a pump rely on water to cool it -
albeit using 'coolant' at 80-odd degrees? Or is water needed to
lubricate the bearing in some way?


The cast iron rotor on our c/h pump is definitely
water-lubricated.

It would sometimes be useful to test a pump dry - by running it
for a minute or so -before fitting it, and I'm trying to assess
the consequences of so doing.


Run dry it *will* score in just a few seconds. Since I
was mending our our pump it was apart, and I was able to
use a drop of 3 in 1 on the bearing surfaces. Ran up ok
without any complaints.

--
Tony Williams.