Radiators downstairs don't work but upstairs do

[kingston]

Had this problem about 8 months ago, got a plumber who said that the pump was knackered, so he replaced it. Don't know if there could be another explanation for this as I have bled the radiators and they are full of water. If the pump has failed again, is there a guarantee, i.e. if the same plumber has to put in another pump, would it be covered under a guarantee and would i get it replaced for nothing, just pay for labour, or is it a general rule that I would have to fork out again for another pump

Hope u can help

Thanks

 

[Bahco]

Try bleeding the pump and the air bleed next to the cylinder first.

You could try asking your plumber if he has guaranteed it.

 

[meldrew's_mate]

Check the pump isn't blocked with sludge as this will seriously impact on its pumping ability. Isolate it either side and undo the 2 or 4 setscrews which hold it in the main body. Catch the small amount of water released and poke or flush the impellor to clear debris.

If it is sludged you should then take steps to flush the system to remove it, preferably not over Christmas in case it won't work after you put it back together

Another thing to check is that the rotor shaft is horizontal so that it can be effectively lubricated by the water, if not the pump life will be shortened.

And finally, if you do have to buy a new pump, pay a few quid more for a good one like Grundfos and follow the instructions enclosed