Balancing C/H system Halstead Ace Combi Boiler

[pacorio]

Hi To All & thanks in advance for any suggestions!

Have tried to balance my C/H system to the 12 deg C or 20 deg F differential across the radiators - its proving difficult if not impossible. Balancing was needed as I had a couple of Rads that were cool and others which were red hot. Having identified flow and returns on all Rads I went round adjusting the flow LSV. Most rads have virtually the same flow and return temperatures as does the main feeds from the boiler. The manual says there should be a differential of 15 deg C at the boiler flow and return but these too are almost the same temperature! I can't slow the pump down as there is no speed adjustment - I could restrict the flow inlet valve to the pump but wanted any suggestions before I meddle anymore - 4 Rads Upstairs 3 Down 7 Rads In total all fed by 15mm pipe off 22mm feeds no TRVs fitted all are now similar temperatures but have similar flow and return feed temperatures!. - Help please!!

Thanks In Advance.

 

[doitmyself]

Having identified flow and returns on all Rads I went round adjusting the flow LSV.

How far are they open?

I don't know which balancing procedure you followed. Try How to balance a CH system, which is based on the procedure advocated by a reputable TRV mfr but applicable to all installations.

4 Rads Upstairs 3 Down 7 Rads In total

We need to find out the total kW of your rads and compare it with the boiler output (11-17kW for CH). It could be that the boiler output needs reducing (GasSafe job)

Use the Stelrad Elite Catalogue to get a fairly accurate assessment.

 

[aggis]

Basically the nearer the rad is to the boiler, the l/s valve req's to be closed more