Can this ever be right? (Radiator plumbing)

[Paul Saxelby]

I'm re-doing my bathroom and need to move the sink, toilet, and radiator.
The radiator in there, I was told, is the one that should always be open. Now then, having got the floor up so I can re-plumb everything I found that there's only one pipe going under that radiator, the return.
There's a T joint feeding one end of the radiator, and the other end connects to a T joint on the same pipe.
The radiator does get warm, but I suspect that's just because some of the water hits the edge of the T and gets forced upward.
The central heating system is a gravity fed one, expansion tank in the loft.

Is there any central heating plan where this radiator is plumbed right?


Many thanks.

 

[stardanny]

Does the rad get hot on HW only?

What system /boiler have you got?

Daniel.

 

[D_Hailsham]

I would check if your other rads have been piped in the same way. If so, you have a one-pipe system. Modern installations use a two-pipe system.

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[Paul Saxelby]

Hi guys - Thanks for the replies.

It's an Icos M3080 boiler with a Siemens RWB9 controller.
The manual for the boiler says that "The central heating system should be in accordance with BS.6798..." if that helps any.

I don't think the radiator gets hot with the hot water...

The other radiators in the house that I can see the plumbing for all look 'normal' to me. Two pipes coming out of the wall, the radiators being connected across the two. For instance, there are two pipes coming out of some boxing next to the back door, there's a radiator next to it connected across the two, and they carry on through the wall to the kitchen radiator, one pipe to each side.

I've never come across a 'one pipe' system - How far back do you have to go for those to have been common? (This house is about 25/30 years old).

 

[baldykev]

Could be plumbed that way to warm rad on hot water as well as C H.So can be used as a towel dryer.Check what Stardanny has said does this rad warm up with hot water on only.

 

[D_Hailsham]

The other radiators in the house that I can see the plumbing for all look 'normal' to me. Two pipes coming out of the wall, the radiators being connected across the two. For instance, there are two pipes coming out of some boxing next to the back door, there's a radiator next to it connected across the two, and they carry on through the wall to the kitchen radiator, one pipe to each side.

It's the bit you cannot see which is more important. There will always be two pipes connected to the rads, but do they connect to the same pipe behind the wall/under the floor, or to separate pipes which then go to the next rad?

I've never come across a 'one pipe' system - How far back do you have to go for those to have been common? (This house is about 25/30 years old).

Single pipe systems are still common in commercial installations (they use approx half the amount of copper piping), but are rare nowadays in domestic situations. Houses build 25/30 years ago would be more likely to have a two-pipe, but if the builder was a penny-pincher ...

 

[Paul Saxelby]

but if the builder was a penny-pincher ...

Going by what you find once the plasterboard is off the walls I'd say it's a good bet they were... :/

I'm fairly sure the rad didn't get hot if only the hot water was fired up. Can't tell now though without balancing it on something & connecting it back up. Didn't expect this to be one of the hold-ups.
I could just recreate the setup in the new position I guess, but I'd like to know that it's not 'wrong' before I do. Really don't want to rip up more floors to find out.

I've attached a pic in case what it shows makes the situation obvious to anyone.
Flow, Ret, and F are written on the pipes, all three of which come out from under the HW tank.
The circled 15mm teeing off the 22mm is the one that pasess under the rad. (It's tee'd to the Ret)

Thanks again guys

 

[stardanny]

Can you find out where the other bathroom rad valve goes to? Look closer, feel...

Daniel.

 

[BigSnoopy01]

it works so dont worry about it, crack on with the bathroom.

 

[D_Hailsham]

I've attached a pic in case what it shows makes the situation obvious to anyone.
Flow, Ret, and F are written on the pipes, all three of which come out from under the HW tank.
The circled 15mm teeing off the 22mm is the one that passes under the rad. (It's tee'd to the Ret)

F is possibly the cold feed to the two tanks in the loft.

So one end of the pipe is tee'd into the return; where is the other end connected to? If it's to the same pipe but further along, you have a single pipe. If it's to a different pipe, which connects to the Flow pipe, you have a two pipe.

 

[Paul Saxelby]

Hi all

Many thanks for the thoughts & info.

Daniel - It goes back into the same pipe it came out of.
Kev & Daniel - Fired things up again and the pipe does get hot with the hot water on.

BigSnoopy - That's pretty much what I'd decided to do

Just wanted to make sure something silly hadn't been done before recreating it on the other side of the bathroom.

Now to go and ask what is probably a very silly new question...