Faulty Radiator? Any Radiator experts on?

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I've recently had a new radiator installed in my lounge and I think it might be faulty but I am wondering if its more down to my system. My old radiator was a large double radiator and it never got proper hot. Even with rebalancing the rads to get it as hot as possible it was never that great (I'd obviously bled the rad as well). Anyway, we decided to get a new rad installed, mainly as it was behind a sofa and we wanted the room to look bigger so we installed a big vertical one about 7 foot further away in the far corner of the room. This was a fairly big job and needed extra piping and here was some talk from one plumber who quoted saying it wouldn't work well due to the distance or the low pressure and even said we would have to re-route the water feed from upstairs (which we didn't end up doing as it would have cost more). Anyways the new radiator works but again doesn't get as hot as we would like and on cold days we have ended up using an electric radiator to add to the heat. Also, we've had a new boiler installed and the system should be clean.

By luck I managed to get hold of a thermal camera (wanted to check the house for obvious bad leaks) and I took a shot of the radiator and it can be clearly seen where the 2 left panels are much hotter than the rest. At the top left the rad is 55 degrees and the bottom right is 41 so about 13 degree drop. I've checked my other rads and the diagonal drop from hottest to coldest is no more than 7 degrees. My thinking is that if the new rad was more even like the rest of my rads the room would be noticeably more comfortably warm. See the pics of the new vertical rad verses an old one in my dining room.

So is this new rad faulty? Could it just be that it's a vertical rad and they are prone to uneven heating? Or could it be my system somehow?
 

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Heat pattern looks about right to me, so I wouldn't think the radiators are faulty.
Heat drop across a radiator (flow in to return out) should be about 11 degrees for a system set up for a non-condensing boiler, and about 20 degrees if condensing.
 
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Heat pattern looks about right to me, so I wouldn't think the radiators are faulty.
Heat drop across a radiator (flow in to return out) should be about 11 degrees for a system set up for a non-condensing boiler, and about 20 degrees if condensing.

Thanks. Do you not think it looks noticeably uneven in the new radiator in the top picture? All my other rads look much more even like the one in the bottom pic.
 
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The top picture appears to show a vertical radiator, the other picture a more usual horizontal one.
Assuming the flow in is on the left, the heat will rise further on the vertical one, leaving less heat to warm the right hand side. Provided the temperature drop across the inlet and outlet is correct this is as good as it can get.
 
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Many thanks for coming back to me, I am researching for a thermal imaging camera and thought the pictures you posted were very good.

There are quite a few videos on youtube regards thermal imagding and houses/buildings.

Andy
 
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Is the boiler set to max?
Did you check with manufacturer is knock outs are part of the rads construction ( when rad can be used in any orientation )
 
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Is the boiler set to max?
Did you check with manufacturer is knock outs are part of the rads construction ( when rad can be used in any orientation )

The boiler isn't set to max - the chap that fitted the boiler said he set the water temperature to 60 or 70 degrees (can't recall, think he said one of these) - what would you recommend?
The radiator was fitted by another chap, a professional plumber, so I assume if it had knock out bits to knock out, he would have done it. I've no idea on the internals on radiators but from the thermal camera it's clearly working. It's not like half of it is dead cold, it's just uneven, with much bigger drop in temperature across it than all my other rads. This is the rad we bought but there's no real detail to go on:

https://www.elegantshowers.co.uk/el...ite-radiator-tall-upright-r6-1645wd-1491.html
 
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If the systems runs and rooms are still not warm enough either water is not hot enough or the rads are undersized for the room .
I “fixed” a friends rads by removing the knock outs after a plumber fitted them and they remained cool at one end .
 
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If the systems runs and rooms are still not warm enough either water is not hot enough or the rads are undersized for the room .
I “fixed” a friends rads by removing the knock outs after a plumber fitted them and they remained cool at one end .

It's a large double rad (1600x452mm) rated at 5630 BTU and the plumber said it was fine size wise. As mentioned the rest of rooms are fine. It probably doesn't help that the rad is in the corner of the room.
I have noticed now that the TRV is on the return side - I've read that modern ones are bidirectional so this shouldn't be an issue?

Also maybe I'm clutching at straws here but I've just watched a how-to fit a vertical rad video on youtube and towards the end he mentions on some rads if you don't connect the flow/returns on the correct side it can mean that your radiator would not be fully heated up.
Is it possible the plumber has done this wrong? (he mentions a resulting N shape heating - mine isn't really like that, just uneven)

See here from 6 mins 11 seconds in:

thanks
 
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Lots of online radiator calculators online which will indicate required size .
 
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Sometimes the flow through a radiator can be too fast. The hot water runs straight across the bottom from flow to return not rising to the top. Slow it up then the hot water spreads across the rad. Many vertical rads are like this. Or it could be too little flow, so open up. Depends on the rad design.

Try throttling down the lockshield valve. Then see via the camera.
 
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Sometimes the flow through a radiator can be too fast. The hot water runs straight across the bottom from flow to return not rising to the top. Slow it up then the hot water spreads across the rad. Many vertical rads are like this. Or it could be too little flow, so open up. Depends on the rad design.

Try throttling down the lockshield valve. Then see via the camera.
Heat always rises, and vertical rads are usually designed to prevent direct thru flow .
 
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