Is there any problem with changing this radiator to a vertical one?

[redhexagonal]

So I have an overpowered wonky 1200 x 600 x 100mm radiator under a window and I'd like to replace it with a vertical radiator to the side of the window. I'm in a new build with double glazing and insulated cavity walls as well as floors/ceilings. The old radiator was probably about 6500BTU at T50, and I'm thinking of a 1780 x 420 double panelled vertical rad that gives 4000BTU at T50.

Is there any problem with the positioning or BTU output of this plan? I have a combi boiler. I guess it would be nice to have some future proofing for a heat pump, though it's not something I can afford right now.

First pic is how the room is now, the second is a photoshop mockup of the position of the vertical rad

 

[terryplumb]

Changing to a rad with less output is usually not wise ,and a lot of these vertical rads leave a lot to be desired in terms of efficiency. Some must have the flow and return into specific ports or they don't work at all.

 

[redhexagonal]

I’ve tried a few calculators online and none of them come out over 4500 BTU. The average is 3500BTU. The vertical rad I’m looking at is spec’d at 4000BTU at T50, which is more output than most of the calculators suggest. My boiler is set at 65 but its probably less when it reaches the rads.

 

[kidgreen61]

Wouldn't be simpler to fit a TRV to it?
Then, when room gets to temp, rad will go off.

 

[redhexagonal]

Wouldn't be simpler to fit a TRV to it?
Then, when room gets to temp, rad will go off.

I want to change the rad mainly for aesthetic reasons.

 

[oldbutnotdead]

How quickly does the room achieve comfortable heat now as it is? Add 50% to that time and that'll be a reasonable clue to the effect of derating.

 

[redhexagonal]

How quickly does the room achieve comfortable heat now as it is? Add 50% to that time and that'll be a reasonable clue to the effect of derating.

Ok I’ll bear that in mind. I’ll have to test it as its set back to 10c at the moment

 

[Madrab]

The vertical rad I’m looking at is spec’d at 4000BTU

Do not spec these 'designer' column rads by their output as they can be very inefficient due to the way they heat the space. The rad you have works by convection and heats a room space relatively quickly, the one you want works primarily by radiation so it heats the space in a quite a different way and depending on the room size, can take an quite a bit longer to heat up the room.

Just worth bearing in mind.

edited for shocking spelling

 

[redhexagonal]

Do not spec these 'designer' column rads by their output as they can be very inefficient due to the way they heat the space. The rad you have works by convection and heats a room space relatively quickly, the one you want works primarily by radiation so it heats the space in a quite a different way and depending on the room size, can take an quite a bit longer to heat up the room.

Just worth bearing in mind.

edited for shocking spelling

So how should I spec a vertical radiator?

 

[Madrab]

Difficult ... as suggested it's all down to the way they heat, I know some that have had them taken out as they just don't heat the room enough, others with smaller rooms that are fine albeit they take longer to heat the space.

The rad does have enough output, it just can't get that heat to warm the space properly, especially large rooms with higher ceilings.

Professionally I never recommend them and caveat them if they insist.

 

[RandomGrinch]

To counteract some of the issues pointed out by @Madrab , I have been very happy with the performance of my Ximax Vulkan vertical rad.
It is a 'tube-in-tube' design which promotes a lot of convection.
Caveats - it's very heavy, a bit costly and needs a decent amount of free air at the top and bottom to allow the convective flow.

 

[Madrab]

And to counter @RandomGrinch 's comments , I have taken out more of those types of vertical rads than I have fitted them and I have another job to remove 2 more next Wed and put in 2 proper vertical convecting rads

As suggested I don't say they don't work but in my experience they don't do the job well in more cases than they do.

 

[RandomGrinch]

And to counter @RandomGrinch 's comments , I have taken out more of those types of vertical rads than I have fitted them and I have another job to remove 2 more next Wed and put in 2 proper vertical convecting rads

I would be interested to know if there is free space around the top and bottom of those!
I think people like the look of having a floor to ceiling rad.
I have properly tall Victorian ceilings with plenty of circulation space around it.

 

[Madrab]

I would be interested to know if there is free space around the top and bottom of those!

Yup, lots of free space, a fair few were in houses that have 3m ceiling height. Column rads are great but they usually need to be way oversized due to the way they heat. Perfect example is the column rads that used to be found in churches, so large the floors needed to be re-inforced in some situations.

That's when radiator covers came in existence, they allowed the air to be channeled and convected in through the bottom of the cabinet and out through the top allowing the column rad to be more efficient at space heating. rubbish when used with convection rads as some designs actually restrict the airflow.

 

[redhexagonal]

Difficult ... as suggested it's all down to the way they heat, I know some that have had them taken out as they just don't heat the room enough, others with smaller rooms that are fine albeit they take longer to heat the space.

The rad does have enough output, it just can't get that heat to warm the space properly, especially large rooms with higher ceilings.

Professionally I never recommend them and caveat them if they insist.

The room is 5.2 x 2.5 with a 2.3m ceiling. Its well insulated with two double glazed windows 1.25m2 each