Strange heating problem

[Probmag]

I have no hot water or heating even though the boiler fires up and the pump is turning. The motorised valve is only about one year old. Water comes out the rads when i open the bleed valves. When the boiler fires up, after about 15 seconds it starts to rumble and then cuts out. After a minute it will fire up again but cut out almost immediately. The pipe above and below the pump gets hot. Any help appreciated.

Boiler is Ideal Élan 2
House is a bungalow
7 radiators

 

[Armo74]

Sounds like the pump isnt operating correctly. Look through the wiki FAQ's on how to make sure the pump is working.

 

[45yearsagasman]

..............and if the pump IS operating correctly, then you have a restriction elsewhere.

 

[Probmag]

Thanks for replies.

I have removed the pump and given it a quick clean and check. Pump appears to be ok. Impeller is rotating on all 3 settings. How do I locate/clear restriction?

 

[Porque223]

Maybe by checking where the pipes are hot besides 'above and below the pump'. There must be (?) flow in the pump area.
With this and the bleed valve clues you may be able to zero in on a pipe section or a valve.
Can you post a drawing of your layout, or that of a typical layout?

 

[Probmag]

Made some progress. Removed radiators and flushed them out with a hose. Noticed the outlet from the tank was partially blocked aswell when refilling the system. Anyway, now have heating and hot water. Still some air in the system I think though, but getting there. Thanks for the help. 👍

 

[Agile]

Sounds like a blocked cold feed!

You should have done the bucket test at the pump!

Your boiler is pretty old now!

Tony

 

[Porque223]

Now that it's working and for future reference you might want to get a thermistor/thermocouple and a meter and map out pipe temperatures at critical points while the pump is running.