How to best balance system

[AlwaysTrys]

Hi,

I have a pressurised unvented megaflo system. 24kw condensing boiler with 9 rads over three floors. I think my boiler may have been speced a little too small as when I have both the water and heating on one of the rads (closest) turns off and a couple of the others become less hot. Anyway the rad in my room is not fully hot and im almost certain my system needs balanceing. Whats the best way to do this.

Thanks in advance.

 

[Deleted member 261]

Usually you have two valves on a radiator one normal one you turn the knob and shut off the radiator, the other one you have to take off the cap and adjust it with a spanner, this is call a lock shield. Close your lock sheld then open then 3/4 of a revolution try this out first with your pump on (2 if possible). If any radiators does not get hot open the lock shield some more on that radiator a 1/4 turn at a time, give it 10 minutes or so each adjustment. If that doesn’t work turn up the pump to 3, if that doesn’t work you need to call someone in.

can you take a picture of your diverter valves and boiler it may be a h/w priority system a

 

[stevetheplumber]

you should also have a balancing valve on the primary circuit to the mega this also needs to be shut down to the point where it just continues to heat the water
in practice i tend to do balancing by ear with the rad shut and system running listen as you open the lock shield and stop when you hear the water start to enter

 

[dan_merkel@msn.]

Close the manual or thermostatic valves on all radiators,
leaving the twin lockshield valves (on the radiators with no TVR)
in the OPEN position.
Turn up the room thermostat and adjust these lockshield
valves to give boiler flow and return temperatures not more
than 20​

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oC apart.
These valves should now be left as set.​

5 SYSTEM BALANCING​

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Open all manual or thermostatic radiator valves and
adjust the lockshield valves on the remaining radiators,
to give around 15 oC temperature drop at each radiator.​