New rad, do I need to balance the system?

redser7

Hi,
As part of a getting a new extension we replaced an existing radiator with a larger vertical radiator. The builder claimed he is competent enough to take care of this. He installed it. At the moment, if all rads are turned on, the new rad takes ages to heat up and doesn't heat up fully, it is luke warm to warm. If we switch off the other rads and heat only the new one then it does get very hot although some tubes are less hot than others.
The rads have been bled so I don't think there is air left in the system. Does it sound like the system needs to be balanced? Would you know roughly how much this might cost?
The original rad was a horizontal single which gave out approx 3000 btu. The new rad is a vertical that gives out approx 7500 btu.
Thanks!

Markcheese

Short answer .yup .

redser7

Thanks. And would you have a rough idea of cost? The old rads seem to heat fine so I'm guessing a flush isn't necessary, just a balance. We have 10 rads.

K.Flyer

Some of those vertical rads have to have the flow and return on certain side otherwise they don't work so well.
Have you checked that both valves are fully open.

redser7

Thanks. No to be honest. The TRV is fully open but I haven't messed with the lockshield valve. To be honest I've only been looking into all this in the last day or so. Kind of getting my head round balancing now and will have a go adjusting the LSVs tonight.
Really hope the rad is set up correctly. It is in the same place as the old rad, he just had to move what was the LSV pipe in nearer. TRV is still on the left hand side. That seems to be a typical setup.

K.Flyer

Before going near any if the other radiator valves, open the lock shield fully on the new rad first and see if that changes anything.

redser7

Will do, thanks!

slinky2000

and make sure the rad is bled!

redser7

slinky2000 wrote: »

and make sure the rad is bled!

When I turn the bleed key water comes out immediately so should be fine.
Thanks