Radiator on feed pipe

[benmw]

This is my first post here so go easy on me.

I recently moved into a house and have a bit of a problem with my central heating where the radiators are all quite cool downstairs. After a bit of research I thought it may be the pump so I have replaced that which has improved the situation a little bit but they are still not as hot as upstairs.

There is however one rad downstairs which is very hot shown below. This radiator seems to be plumbed in line with feed pipe (coming from above on the left side) i.e. it is feed from the feed pipe and returns in to the feed pipe in such a way that all the hot water must flow through the rad. It is also in the kitchen next to the back door so I think it is taking a lot of the heat before it has a chance to get to the rest of the rads downstairs.

Is this a normal way for a rad to be installed? I was under the impression that they should be feed from one pipe and then return to another unless they are the last one in the chain when they would close the loop (this rad is the first in the chain downstairs).

In this case the return pipe would be difficult to plumb the rad into which probably explains why it is like this. So what I would like to know is would it be reasonable to plumb this rad in as though it were on a single pipe system i.e. on a separate loop off the feed pipe? and would this help my situation?

Thanks for your help
Ben

 

[Whitespirit66]

What happens to the other rads if you turn this one off?

 

[benmw]

They go cold which makes it hard to understand the TRV

 

[Whitespirit66]

So it looks like this rad is plumbed into a flow pipe to the other rads. That explains why your other rads are cooler. No, this is not the correct way of doing this.

Are all the other downstairs rads equally 'warm'?

Sounds like repiping to a correct 2 pipe layout will stop this rad robbing the others of heat. How easy that will be to achieve depends on the construction of your home.

 

[benmw]

The other downstairs rads are all comparably warm. Do you think as a temp measure it would be worth putting this rad on a loop off the feed pipe as to my mind this would then allow me to limit the flow to this rad with out impacting the other downstairs rads.

 

[Whitespirit66]

The easiest temp measure for now would be as in example 1. Join the two pipes in and out of this rad beneath it. This will mean that the rad is piped as on a one-pipe system, and stop it robbing the others of heat.

Slightly more difficult would be if you couid disconnect the right hand pipe, and get a proper return pipe to it, from else where in the system as example 2. Then just connect the pipe in the floor to the pipe on the left that goes into the TRV. This is probably a more difficult option as it relies on you finding a nearby return pipe. But it is a slightly better option.


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[benmw]

Thanks for your help solution one was what I was thinking and then when we re do the kitchen solution 2. There is a return pipe on the other side of the wall and in fact pretty much under that rad but it is a solid floor so getting to either one would require much more effort than the fist solution.

 

[Whitespirit66]

One last thing. If going with option 1, change the TRV to a standard wheel head valve. If you're piping rad as in one pipe systems, this relies on thermo-syphon into the rad.

Standard TRVs kill this syphon effect. Other alternative is to fit a TRV for one pipe, like Danfoss RA-G, but pricey.

 

[Nige F]

I think Drayton made a TRV for one pipe Well , I`ve got a few in my garage and they have bigger internal waterway than the normal trv 4 -Took them off and put on trv4`s because I couldn`t get any decorators caps to screw them down tight - Will probably put them on eBay