5 months of torture and nobody can fix

[alemck629]

hi, i have recently pulled down walls, built a new sunroom and have problems with one radiator that nobody seems to be able to fix. I have upgraded my boiler to a Worcester Bosch 30KW, this is a regular gravity fed system. I have put underfloor heating into the sun room.

I have an 1800mm radiator that just does not get hot, the flow is boiling so is the return, i have balanced the system. bled it. If i mess around with bleeding i can get 3 panels of the 5 panel rad warm, as soon as heating goes off and back on it is stone cold. I have also had a replacement rad and it does he same. Nobody can fix this, can anyone help? A new Groudfos pump was also installed.

when electrician installed electrics for this he said my heating was wired wrong and he fixed it. Been in house from new 23 years and no issues previous. I have BG hive and Speedfit underfloor heating.

Thanks in advance

 

[Ian H]

Could the inlet and outlets be the wrong way round?

 

[alemck629]

you mean the flow and return? I really don't know the radiator in question is a replacement of a smaller one, as i have opened up the downstairs it is a very large area i put a 11500 but radiator in, i also have 2 x 1000x 550 rads in too, all other rads heat fine, i am constantly bleeding the towel rad in my ensuite upstairs. I have had British Gas out, private plumbers and nobody knows why, the water seems to be going straight through. There is a flow diverter in the rad so the water hits it and goes up the way. I am baffled by this and so is everyone else

 

[alemck629]

I have 14 rads in total and my underfloor heating in the sun room. Plumber thinking about putting mains water into my system to try and increase pressure.
Alex

 

[picasso]

Probably got both pipes connected to flow so both pipes hot but no flow through the rad.

 

[alemck629]

They are using the same pipes that fed previous rad I believe. If I turn all other rads off this one on only it gets hot plumber says that would not happen if 2 flows. This was done by Kitchen International Plumber’s.

Alex

 

[picasso]

1800 is a big rad, how many rads you got feed off the same 15mm pipes?

 

[terryplumb]

The rad is a vertical as I understand. Is the baffle ( diverter ) on the side of the flow pipe ? If so ,and if this rad heats up fully when all other rads are turned off ,it sounds like a balancing problem . what size pipework feeds this troublesome radiator ?

 

[alemck629]

Hi thanks for reply yes flow diverted in at flow side I got the manufacturer to do on replacement to ensure right spot think pipe is 15mm. Yes rad heard up if all other off. It is all baffling

 

[picasso]

How many rads off the same 15mm pipe ?

 

[alemck629]

I have 15 rads in total underfloor heating in one room that is about 6mx7m alt 6m high 30kw boiler

 

[alemck629]

I have fully redecorated hardwood floors and skirting reluctant to pull everything up fo obviously reasons

 

[breadnbutter]

could be faulty rad valve, or something has gone in rad partially blocking it.

 

[petit_pablo]

Sounds like a lack of flow to me. The resistance on these designer rads is high and its a big rad too. Pressuring the system will unlikely help here. Repiping from the primaries to that rad and properly balancing the rest of the rads would be my suggestion.

when electrician installed electrics for this he said my heating was wired wrong and he fixed it.

May have been, wouldnt have stopped rad working though.

 

[FiremanT]

Sounds like a lack of flow to me. The resistance on these designer rads is high and its a big rad too. Pressuring the system will unlikely help here. Repiping from the primaries to that rad and properly balancing the rest of the rads would be my suggestion.


May have been, wouldnt have stopped rad working though.

Thinking the same thing.

Plus - most electricians would not know, anyway.