CH Pump Stalls when hot

[Gilray]

My central heating pump works fine until the the heating/water has been on for some time (around an hour) and every thing has got nice and hot and then it stalls and refuses to start. Ive tried giving it a kick start by undoing the spindle cap and manually turning it but that doesnt work. I can cool it down with a damp cloth and it will eventually go again.

The Pump is a Circulation Pumps CP53 -

has anyone else had this problem?

Is there anything I can do to fix the pump or is a replacement job?

Should I fit the same one or would I be better off fitting (say) a Grundfos 15/50?

 

[Whn1]

Sounds very strange, what makes you think it's the pump? Cooling it down could just be a coincidence.

Grundfos all the way.

 

[kozak1968]

A new pump should be fitted. "A" rated pumps such as the Grunfos Alpha must be fitted now. ( you can still get the 15-50 pump if the alpha is too expensive)

 

[Whn1]

I just checked out grundfos website kozak and they're saying they're stopping the b rated pumps... So soon you'll only be able to buy the a rated, alpha and ups 2.. Is this true?

 

[kozak1968]

January 1st 2013 i think was when "A" rated pumps had to be fitted.

 

[Whn1]

January 1st 2013 i think was when "A" rated pumps had to be fitted.

Whoops.

 

[snowhead]

To the O.P

Have you got Thermostatic valves on All your rads?
Do you have a by-pass either manual (is it open) or Auto (is it working)?

 

[kozak1968]

Dont tell anyone!

 

[Gilray]

The pump has 230V across it but is not running and will not start by turning spindle. Will start when cooled down.

 

[Whn1]

New pump, treat yourself to a grundfos.

 

[lame plumber]

do a resistance check across pump when hot, probably breaking down on coils. Ive yet to meet the pump police enforcement team!!

 

[dave1]

My central heating pump works fine until the the heating/water has been on for some time (around an hour) and every thing has got nice and hot and then it stalls and refuses to start. Ive tried giving it a kick start by undoing the spindle cap and manually turning it but that doesnt work. I can cool it down with a damp cloth and it will eventually go again.

The Pump is a Circulation Pumps CP53 -

has anyone else had this problem?

Is there anything I can do to fix the pump or is a replacement job?

Should I fit the same one or would I be better off fitting (say) a Grundfos 15/50?

If its been in for an hour and then it stops are you sure it's not just that the system is up to temp.

 

[Whn1]

If it had reached temp should be no 240v to pump unless pump overrun in which case it should still be running.

 

[MRDrip]

Grundfos alpha 2 - so so quiet, and saves on the leci too. Just get one.