RadFan

Spies

A few years ago I replaced my radiators with the largest ones that would fit without adjusting the plumbing.

The room has a very high ceiling and typically it takes 3 hours for a 3c increase (based on todays temperature of 5 to 6 degrees), I run the CH side of the combi boiler at 75c

Now in my mind increasing the airflow should mean that temperture in that room should climb faster meaning less gas use? Am I wrong? These solutions seems quite expensive for what they are but I guess they need to withstand high operating temperatures...

What are your thoughts?

EssexExile

Logic says to me that there is only so much heat coming out of a radiator, putting a fan on will just move that amount of heat about.

Norman_Castle

Convection radiators move heat from the radiators without fans. The warmed air in the square tubes rises drawing colder air from underneath.  Assuming you've got convection radiators is there clear space above and below them?

fenwick458

if you have a fan blowing air past a radiator, it's going to heat the room up more but it certainly isn't going to use less gas, it'll use more!

Spies

fenwick458 said:

if you have a fan blowing air past a radiator, it's going to heat the room up more but it certainly isn't going to use less gas, it'll use more!

But the main stat is in that room so surely the boiler will go off sooner? 

Bendy_House

Hi Spies.

Are your current rads properly hot to the touch? If not, then fanning more air from them is unlikely to help.

I've had a look at these radfans, and see how they are meant to work. I'd assumed that 'all' they did was to blow more air through the rad so it would remove more heat from the water and send this to the room. But actually what they do is to gently blow the rad's air horizontally out from the top of the rad, so that you feel the effect of it more directly - ie the heat is being driven out at around waist height, or body height if sitting down; you are bathed in the warm flow.

The idea is that the folk in the room are directly benefitting from the heat from the rad, rather than waiting for it to heat up the whole room - from the top downwards... Therefore, even tho' it can be argued that it does take more heat from the rad - so this means the water is cooled more so needs more gas to power it - in actual fact since people 'feel' more warm due to the directly-aimed air, they turn the room 'stat down to get to the desired temp level. Overall, then, there is an energy saving. (According to the manufacturer, which apparently has had it trialled in Housing Assoc homes).

So, will it work for you, Spies? No idea. But I'd say that if it does actually work in general, then high-ceilinged folk like you would be the most obvious beneficiaries.

Spies

Yes my radiators are pretty hot, wen I use my infrared thermometer it shows 70c on the side where the water flows in.

They're evenly heating up too, just as you say it's the height that's the issue, some architects should be shot, it's a 1996 property, the space towards the top of the room isn't really useful anyway as it's a mezzanine! 

Effician

Ceiling fans over rad fans every time for rooms with high celings.

Spies

Effician said:

Ceiling fans over rad fans every time for rooms with high celings.

Mezzanine in the way so that won't work unfortunately. 

Effician

Maybe a 16" pedestal fan  on the mezzanine to push the warm air down, got to get that warm air down somehow.

Spies

I'll give it a go.