CH Pump Problem

[yartin]

I turned both valves clock wise and anti clock wise with no issue, does this confirm valves are in working order?

 

[fixitflav]

I turned both valves clock wise and anti clock wise with no issue, does this confirm valves are in working order?

Do you mean the pump iso valves? From the pic they are multi-turn gate valves. If they go several turns both ways before meeting resistance they should be OK.

 

[yartin]

Do you mean the pump iso valves? From the pic they are multi-turn gate valves. If they go several turns both ways before meeting resistance they should be OK.

Yes I did few turns clockwise until stopped then anti clockwise until stopped.

 

[Johntheo5]

Yes I did few turns clockwise until stopped then anti clockwise until stopped.

Suggest, opening & closing them several times, each time when shut give a little extra squeeze up which will help to get a effective seat/seal, when satisfied, remove (with boiler&pump isolated) that pump centre screw again, get a screwdriver or whatever and just push in the shaft a few mm, if no water, then you are good to go, take a snapshot of the pump wiring in its terminal box, remove the wires, remove the pump after carefully noting the direction of the arrow on its casing, clean up the flanges, install your new pump, wire it up, open the isolating valves and away you go.

Hadn't read post #45 so yes, try this first, have you established if the pump shaft is in fact turning??.

 

[yartin]

It shouldn't be too difficult to remove the pump body to check the impeller etc, just 4 Allen bolts. No need to disturb the pipework. Close the pump valves first, or if you prefer, partially drain the system.
It would be a shame to replace the pump and find it's no better.

There is no other parts which can be faulty. The boiler fires only for 30 sec then stops for 30mins or so, the feed pipe from the boiler get very hot and return is cold, then the pump get very hot for no good reason. What else good it be, boiler?