radiator fans

Brie

I'm wondering how useful these are.  I've seen some for sale at Lidl recently - at least I think they were for rads and not wood stoves.  But it seems to me that a simple fan that is moved by the rising heat would be a useful thing to move the heat away from a particular wall and across a room.  Any ideas on ones that go on top of a rad rather than on the front and that can be swiveled to push heat where you want it rather than straight out?

Reed_Richards

You can improve the efficiency of a radiator by using a powered fan (or fans) to force heat through it.  You can buy fans to do that if your radiator is a standard size.

Hot air will tend to rise so if you would benefit from sending hot air out and then up, rather than straight up, then you might benefit from an unpowered fan.    

bob2302

The one I saw in Lidl was for wood burning stoves. I think it worked by using the high temperature of the flue to generate electricity from a thermoelectric generator. If that's what it was doing,  a radiator might not be hot enough.

Scot_39

Any fan that will increase air flow across and if can mount it / position it - divert some heat from pooling - above the radiator can actually reduce your heating cost.


And adding greater air flow can even boost effective power at a given flow temp - speeding up time to warm room - or keep the same e.g. if drop flow temp for boiler and pipe loss efficiencies.  But overall energy costs remain similar to heat the space.

If there is poor circulation - the space around and more so above the radiator all the way to ceiling will be in many cases a few degrees warmer than the air your sitting in.

Either pulling that cold air from say middle of room  towards the radiator at say floor level, diverting the convection air flow at tge top of radiator, or as common in other nations reversible ceiling fan (for cooling in summer, hest distribution in winter) can help prevent heat pooling where not required to "heat" you (reduce body losses)

Before spending c£50 - on a bespoke model - if you have any desk or room fans - just try that first.  Even small 5w USB can make a difference if really poor airflow.

I use little fans to force circulate air from unhet to het rooms sometimes passive  flow not quick enough.  Including my "unhet" once doors closed bedrooms on really cold mornings.

dealyboy

I use my de-humidifier for said purpose ... helps the de-humidifier as well by allowing it to operate at otherwise low temperatures.