Balancing to accomodate new rads

[rolyatescort]

Hi Guys,

Let me apologise in advance as i know you must have been asked this a thousand times. I have searched the forum but i have discovered a few conflicting answers so i would like to be certain.

I have a Potterton Combi Boiler feeding 8 rads. (4 up 4 down). Downstairs in order of utility room then kitchen then dining room then lounge. Upstairs is bathroom then landing then spare room then master. The upstairs rads all work fine though the bathroom one has been the first to suffer if there is a pressure loss on the system. Downstairs is the problem, utility and kitchen both get red hot, dining room warm/hot lounge nothing at all. I didn't bother working on this until this week as i wanted to replace both dining room and lounge rads which i have now done. At the same time i discovered and repaired the leak that was causing the pressure loss. I have turned off all rads except lounge and this has forced hot into it. I am now trying to balaance the system but at not getting anywhere fast.

Could someone please give me an idiots guide to balancing my system?

Thanks in advance.

 

[kevplumb]

get yourself two clip on thermometers
set the temp drop across the rad to 9deg by closing the locksheild valve 1/4 turn at a time and give the system time to settle between adjustments
long slow process

 

[rolyatescort]

Thanks for replying Kevplumb,

What sort of clip on thermometers, can i just get them from a DIY store?

Cheers

 

[kevplumb]

yes dail type with a spring that goes round the pipe think b&q do them

 

[ChrisR]

I've got a differential thermometer with strap on probes for doing that. Used once. Not enough excess life left to ever do it again.

Most rad valves are 3 or 4 turns from full shut to open. After opening about 2 turns, the rest doesn't do much. ie half a turn open is something like half way to full open.
Try having the rads nearest to the pump, in terms of pipe length, about 1/4 turn open, and work your way to full open (ie 2-3 turns) for the furthest. If you have Thermostatic valves they help to compensate for small errors cos they shut themselves.
Always seems to work for me, give or take a tweak or two

 

[fronnie]

One method i use is, usually have 2 people for this. (only on houses with small numbers of rads or you will need hundreds of people ) open all rads fully, turn the system on.
Walk round the rads and make a note of the ones that get hot first , the ones that get hot first shut off the lockshield fully and open 1 turn. Then do the rest accordingly ie open 2 turns etc.Should work a treat if you dont have thermometers.