Cold Rad, Hot Pipe

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Hi guys,

I've searched and searched and I can't find an answer to my specific problem. We decorated a room for our little girl to move into, and the Wife wanted the radiator moving from one wall to another. It was initially a regular double panel radiator, which was mounted on a wall with the pipes coming through the wall into the eaves, as the room is in the roofspace. It had a long "loop" of pipe which serviced it, which I cut short and ran pipes from it under the floor, to the other side of the room. We now have a column style radiator installed, with a TRV on one side.

Now here's the problem, the radiator doesn't get hot, at all, it barely increases in temperature. The pipe leading up to the TRV gets nice and hot though. I've took the head off the TRV and checked the pin moves up and down freely, which it does. I've turned off all other radiators, and the same still happens to this rad.

Everything is brand new; the radiator, valves, pipes, the lot.

Here's a rather crude drawing, including the hatched out previous installation, and overall plan of the room with new rad positioning:

Capture.jpg



Please help, my little girl is cold ;)

Many thanks,

Carl...
 
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It's not cold yet :LOL:

Are you sure the valve at the opposite end of the radiator is open? You wouldn't be the first to forget that!

Is the radiator the right way round? Modern column-style radiators are often sensitive to which end is piped to flow, and which to return. Get that wrong and they won't get hot
 
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As above ,but some can be put on upside down . That also will not work as the baffle has to be on the bottom.
 
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Hi guys,

Sorry for the delay, only just managed to get it off the wall. You can see daylight when looking through the top and bottom valves, so there's no baffle. I'm at a bit of a loss now. Any heating engineers in the North East on here who could squeeze me in?

Cheers,

Carl...
 
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Hi guys,

Sorry for the delay, only just managed to get it off the wall. You can see daylight when looking through the top and bottom valves, so there's no baffle. Both pipes have pressure. One gets hot, the other just a little warm.

I'm at a bit of a loss now. Any heating engineers in the North East on here who could squeeze me in?

Cheers,

Carl...
 
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Hi guys,

Sorry for the delay, only just managed to get it off the wall. You can see daylight when looking through the top and bottom valves, so there's no baffle. Both pipes have pressure. One gets hot, the other just a little warm.

I'm at a bit of a loss now. Any heating engineers in the North East on here who could squeeze me in?

Cheers,

Carl...
 
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Looking at your sketch ,it looks like a single pipe system ,is that so ? And it looks like you have used two "T" unions to the radiator, is that so ? If it is you have dropped a clanger Carl.
 
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The hot water from the boiler would just travel straight along the pipe if it was connected the way you think . are you sure the pipe didn't enter the rad on one side ,and exit on the other side ?
If you can access the pipe work ,I'll wager its very hot before and after the rad.
 
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It 100% was plumbed the way I've done it. I was confused too, as I thought it shouldn't work. I guess if I can work out if it's single pipe system, then I can remove the bit between the T unions.

Does anyone know how I can find out?

Also, is it possible to have a "hybrid" system, where most rads are fed with the usual flow and return, but this one rad is fed with a single pipe?

Cheers,

Carl...
 
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What size pipework ,and is it copper or plastic ?
How familiar are you with pipework elsewhere in the property , are there manifolds on the central heating system ?
How many other radiators do you have that are connected with " T' s to one pipe ,that work well. When you find one please post a pic here.
 
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Nothing wrong with Tee'ing off a single pipe system BUT there needs to be some distance between the tee's (normally the width of the rad), as such a system relies on the pressure drop between the two tee's (due to the pipe friction) to get the water to start circulating around the rad.
Perhaps something like this would be better. The S shape pipe retains the flow of the single pipe system if the rad is shut off and the length of the S pipe provides the distance between the tee's.

Drawing1 Model (1).jpg
 
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What size pipework ,and is it copper or plastic ?
How familiar are you with pipework elsewhere in the property , are there manifolds on the central heating system ?
How many other radiators do you have that are connected with " T' s to one pipe ,that work well. When you find one please post a pic here.

Sorry for the radio silence chaps, been dealing with a leaky roof. It never rains, but it pours, as they say.

Terry, I'm not very familiar with the pipework in my house, but I do plan on taking a trip into the crawl space under the house tomorrow, to see what I can find. I'll report back once I've done so.

I've never come across any manifolds, but then again I've never really been looking for any. Again, I'll take a butchers for one tomorrow.

Not sure how many other rads are connected with T's to one pipe, but should find out if there are others tomorrow.
 

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