We have got a problem with the downstair radiators being cold.
System is a standard boiler & tank, house is a two storey (the top story was added after the heating system however heating used to work ok)
Upstairs gets warm, downstairs doesnt. If the rads are turned off upstairs then downstairs gets heat.
british gas (three star cover) have been many time but cant solve it (fitted
3 new pump and powerflushed the system at great expense). They have also said that it cant be the boiler or boiler size?Can anyone suggest what it can be?