still having problems with no hot water downstairs

[drew13]

hi all sorry to ask again but can anyone suggest an answer to my problems... i have no hot water coming out of the hot tap in the kitchen only cold .the only time is does get hot is when i turn any of the taps on upstairs in the bathroom and the hot tap "asks" for the boiler to switch on .this does not happen when i turn the tap on downstairs so i only get hot water if i leave a tap running upstairs .someone suggested a flow problem and the flow is pretty poor downstairs .i took off a section of pipe to replace the taps and found it solid with limescale could this be further down the pipe?i don't want to take the kitchen apart and find its the boiler.i have a worcester 24i combi boiler
cheers
Andy

 

[Rob]

Just measure the flow with a jug or something. Aim for atleast 4 ltr min. which is a ltr every 15 seconds or roughly a pint every 8 seconds

Never knew limscale biult up in copper pipes but this could be the case if all other taps are ok.