Radiator Balancing Query

[gatman]

I'm trying to balance my CH system and have read the FAQ etc.

I have opened all valves on all radiators and then turned the heating on. As the water started to warm up I closed the lock valve on radiator number one and then opened it slightly. The temp on the inlet rose to 44c but no matter how long I leave it the outlet won't go above 20c and the radiator doesn't get hot. As soon as I open the lock further the radiator gets hot but the temp difference is still 20-30c.

If I resort to plan A and then do the other radiators will the first radiator then get hot or would it stay luke warm?

Thanks

 

[John506]

Was the TRV closed?

 

[gatman]

The TRV was fully open.

 

[John506]

Hmm maybe a blockage? What happens when you do the same on other rads?

 

[gatman]

Don't think there is a blockage. I've bled it as well.

I've just had another quick look and the radiator gets scalding hot on both inlet and outlet if I open the lock half way. It may just be a case of playing around with it until I can find the correct drop. All the other radiators get hot to warm as they progress in number it just seems to be this one. S**s law it's the first in line and is a big one.

Any idea if I should let the radiator get to a uniform temp all over and then try again or as soon as the inlet starts to get warm open it up a bit?

 

[TicklyT]

Don't expect to get it right first time around - adjusting each rad. will affect all the others in the system, including the ones you think you have already set up. Just keep going around them all. By the second or third lap you should be getting results close to the ideal.

 

[gatman]

Thanks all, still trying but it is really frustrating

I finally managed to get a steady 12c drop on the first radiator but when I was trying the second, the first has a hot inlet but cold outlet now. Is that right or is it to do with it being the first lap etc?

Also, I can't get anywhere near a 12c difference on the second radiator. The lock valve is on the outlet and a TRV on the inlet (the TRV is removed so just the open valve now). Each time I try to adjust the temp, the inlet side gets hotter giving an even bigger difference. The TRV valve has an arrow pointing in both directions so I presume it's a bi-directional flow? Importantly, does the lock valve have to be on the inlet rather than the return?

Thanks

 

[gatman]

Having read the FAQ's re balancing could someone confirm the following:-

Open all the TRV's and lockshields.

Calculate the radiator order.

When cool turn the CH on.

Go to first radiator and almost close the lockshield. Do I adjust to a 12c change even if the first radiator doesn't get hot just luke warm?

Also when I've done the first and go on to the second, do I start again with a cool CH system or with the now really hot CH?

Finally, does it matter if the lockshield is on the return rather than the inlet?

Thanks for your help.