Radfan Classic

It's such a pity the likes of Amazon don't sell this product.

As if they did then you could read their customer reviews.

All 829 of them.

HTH

In message , Moron Watch writes

My impression of amazon reviews is that they are often written by well meaning people like my ever loving wife - which is why I asked here.

Well fan blown rads are smaller for same power output.

So the principle works

Whether its worth it as aftermarket addition is moot.

Excellent idea. The waste heat from the fans will help heat the room. Using more expensive electricity, of course. And the noise will be welcome too.

Exactly what I was thinking!

In message , "Dave Plowman (News)" writes

Indeed. The whole point of these things is apparently to redirect heat, not give heat. I'm not convinced, and am rather hoping (quietly) that someone is going to give me a good and compelling reason to tell Wifey why we don't need to waste our money.

Graeme submitted this idea :

Last winter a friends wife was telling me she was always complaining one their rooms was always too cold. I suggested that a simple fix was to put a fan heater blowing cold air, under the radiator to increase the air flow/ increase the temperature. That worked. Faster air flow, more heat transferred from rad to room.

So far as this item is concerned - yes, no reason why it wouldn't work better, but I cannot see it saving much gas, if any - certainly not its £40-£50 anytime soon. Then there is the small running cost on top.

If it accelerates the airflow through the radiator. it will increase the output. If not, it won't. I 'spect it also claims to reduce heat loss by directing the warm air away from the cold wall. Possibly true but the effect is miniscule.

Unless you have a problem with the room being cold, I wouldn't bother.

There might be a noise problem with the fans too.

Snake oil.

A more cost effective means is one of those reflective insulated panels that fixes on the wall behind the radiator. Especially if it's a poorly insulated outer wall.

Radiators are misnamed because most of the heat is convected compared to the amount radiated.

I would have thought (no, really!) that you'd be better off blowing the air down through a double radiator.

I suppose it depends on whether you heat the room above, if there is one. Buy one of these...

...it'll pay for itself in decades, and it's great fun.

Cheers

I was wondering about top floor rooms. There, any heat loss through the ceiling is effectively completely lost.

No it won't save fuel. What it does is increase radiator output.

What happens overall depends where the room-stat is, if it's in the room where a radfan is, then that room will warm up sooner and it will stop calling for heat, so may save gas ... but other rooms may not have warmed as much during the reduced heating period, so "someone" may then turn the stat up to warm the other rooms, or insist on radfans for those rooms too!

Depends what you want to achieve!

If a radiator is undersized for the room it's in, you can increase its capacity by using forced convection rather than natural convection.

The boiler will need to work harder, and will use more fuel. The fans will, of course, make a noise and increasing the water flow may cause pipe noise, depending on whether you're already close to the critical flow velocity.

I would think long and hard before I bought one of these things.

I've done exactly that, but using one little PC fan placed under the rad ru n on IIRC 6v. What it achieves, by increasing the airflow over the rad, is to extract more heat from it. Useful if that's what you need, and you don't want to replace with a bigger rad for some reason. In my case there wasn't space to. The result was a room 2C warmer, just what was wanted.

There was a long running argument with an idiot called Onetap on here, who was incapable of figuring out what it did & how.

If you need a bit more output, great. If not it's simply pointless.

Re noise, I don't know why people think all fans are noisy. It's trivial to make silent fans as long as you don't want much airflow. I've not used the radfan so no clue what the noise level is, if any.

NT

A few years ago I had a radiator which wasn't giving a decent output because the 10 mm microbore was either kinked or partially blocked with solder between the floors. As an experiment I lashed up a somewhat similar system with a couple of PC fans blowing between the two panels to get some forced convection from the "high output" fins, and it did seem to improve the room temperature a bit. I subsequently replaced the microbore with proper 15 mm pipe and the problem went away.

run on IIRC 6v. What it achieves, by increasing the airflow over the rad, i s to extract more heat from it. Useful if that's what you need, and you don 't want to replace with a bigger rad for some reason. In my case there wasn 't space to. The result was a room 2C warmer, just what was wanted.

o was incapable of figuring out what it did & how.

to make silent fans as long as you don't want much airflow. I've not used t he radfan so no clue what the noise level is, if any.

Quiet fans are less efficient.