ground floor radiators not working.

[rowie]

my problem is that none of my ground floor rads are getting hot.
The system is piped in so that the hot water circulates from the boiler (situated on ground floor) to the upstairs first and then back down to the ground floor.
My suspicions were that the pump was not working, and the upstairs rads were getting hot due to Gravity/ hot water rising.
I have checked the pump ( grundfos 15/50 ) by unscrewing the cap from the front, and the spindle was spinning freely when the boiler was on.
This would indicate that the pump is working would it not ?
Does anyone have any ideas ?.

 

[gas4you]

Not always. It can spin but be broken so it will not circulate.

 

[alan m 1974]

Close upstairs rads off by trv or l/shield valve and close d/stairs bar one rad and see if it comes on ,if ok,go to next one and open ,and so on