grant back boiler and flowpipe does not heat properly

[emoore]

Hi
Sorry to bother , but i have back boiler grant style and the flowpipe appears to be luke warm and radiators fail to heat up sufficiently only luke warm. I was wondering maybe the pipes were not linked into the existing hot water tank system properly as it has dual tank and motorised valves. Can anyone advise.

Much obliged

E:icon10:

 

[SimonJohns]

Have you had it serviced in the last year?

 

[emoore]

Brand new open fire back boiler. Just don't understand that fire is blazing and the flowpipe i cool to luke warm and my sister's fire the flow pipe is untouchable.

E