new loft radiators not getting hot

[bonksmith]

Hi all, i've recently had my loft converted and have added two new radiators, which are not getting hot. They have been connected of exsisting first floor pipe work and have been bled, they also have T.R.Vs fitted. All other radiators are getting hot and i have Worscester/ Bosch 28cdi combi boiler, any help would be greatly appreciated.
many thanks
Bonksmith. [/b]

 

[kevplumb]

close the others down

what size pipe was used

 

[bengasman]

How did you choose the pipes/points to connect the new rads into the existing system?
Did you balance the system?
How far are the lockshields on the new rads closed?

 

[Gasop]

Could be the system pressure a bit on the low side, try at about 1 1/2 bar

 

[bengasman]

Could be the system pressure a bit on the low side, try at about 1 1/2 bar

How would more pressure increase the flow?

 

[bonksmith]

close the others down

i used 15mm pipe, straight off exsisting pipework.

hat size pipe was used

 

[bonksmith]

How did you choose the pipes/points to connect the new rads into the existing system?
Did you balance the system?
How far are the lockshields on the new rads closed?

I chose the pipes which gave the most direct route up to the loft. i've not balanced the system, not sure how and the lockshields are fully opened.
Hope this helps cheers

 

[bengasman]

How did you ascertain that the pipes you teed into were actually main flow and return?
Balancing the system is essential; see faq

 

[jackthom]

close the others down

:

Have you tried this to see if you can force the hot water around the extension radiators.

 

[bonksmith]

How did you ascertain that the pipes you teed into were actually main flow and return?
Balancing the system is essential; see faq

I followed the pipes back from the first floor bedroom radiator.
Cheers.