On Wed, 22 Sep 2004 14:09:33 +0100, "AK" wrote:

I am going to balance my radiators this weekend, I just want to check some
facts that hopefully some of you can help me with.

I need to open up all the control and LSVs and find out what the flow is and
find the index radiator. As I understand it the control valve should be
where the flow is in and the LSV on the outflow. Two of my radiators appear
to the the other way round - is it a simple matter of just swapping over the
knob from the control valve and putting it on the LSV?

Hello Angela,

Most of your points have been covered by others, but just to clarify one
or two things...

Do I leave the index radiator fully open

The term 'index' is a very old one deriving from a crude rule of thumb
design method. What they mean by 'index' is simply the radiator that has
the most resistance to flow. It is the one that has the longest/thinnest
pipe run and is often (but not always) the furthest from the boiler.
This one should have both its valves wide open during balancing.

and work back to the boiler or do I
start from the radiator closest to the boiler?

Start by opening all of the valves on both sides. Then generally the
Rads closest to the boiler will take more than their fair share of the
flow so you will start by turning them down to get a larger temperature
drop.

From what I understand I might have to adjust the speed of the pump. I have
no idea how to do that! I have a Potterton Puma 100 boiler and I can't even
see a pump let alone adjust the speed! I understand that some boilers have
automatic pumps - is that right? Does my boiler have one?

There is usually a switch or dial on the pump itself, marked 1, 2, 3 (3
being fast) or similar. The pump may even be under the floor, in which
case don't worry unless you really suspect a problem with it.

Is it correct that the drop needs to be 20 deg F?

No. What matters is that all rads have roughly the same drop and have
really hot water reaching them. In other words they are all getting HOT!

TIA

Angela

Phil
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