Radiator Booster - any thoughts?

rogerblack

crizmo wrote: »

Thanks Scorpio Biker. I was wondering when someone would say what they thought after using the product instead of giving me physics lessons.

It is unfortunately going to vary hugely.
In Scorpios case, it sounds like the radiator was either obstructed, or undersized.
This will reduce its heat output.
A fan will bring it back up to (or beyond) normal, but it will not change significantly the amount of energy from the boiler needed to heat it.

You can't generalise from this case.

ViksB

We have a radiator booster not to save energy but to boast the radiators. Our kitchen have a very undersized radiator and the radiator booster does make a surprisingly large difference, i.e. the room is actually warm rather than cold. I don't think it will save money but it does make poor radiators work better which for us is great.

Mayen

I built one of these to my own design as I was concerned by the reports of noisy fans and poor build quality of the manufactured unit.

I used 12V fans with 6V power supply to reduce noise & thermostatic sensors for automation. As I have old radiators I've side mounted the units blowing into the rad as they appear more effective like that.

These definitely work, the room gets warmer quicker and I've been able to turn down the boiler thermostat. I can't give any precise energy saving figures though. The fan units are using around 0.5watts, which is tiny.

I am surprised at the people failing to believe blowing air over a radiator can increase heat transfer! I assume they all drive around with their car radiator fans disabled too!

Mayen

rogerblack wrote: »

In short, low power fans on radiators may slightly lower your central heating loop temperature, and have very small positive effect on efficiency.
Similarly, reducing the temperature of the wall behind the radiator may do a small amount.
But, you,d get a similar effect with something like (links to large fans)

I did try a single largish fan originally, but found its effect small, I would put the cause down to the localised air flow, a widespread directed flow providing a definite improvement.

Cardew

Mayen wrote: »

I am surprised at the people failing to believe blowing air over a radiator can increase heat transfer! I assume they all drive around with their car radiator fans disabled too!

I didn't think people were disputing that a fan increased heat transfer; the issue, on a money saving forum, was if they saved money.

The concensus is surely that it can only have a marginal effect(either way) on boiler efficiency by effectively having a bigger radiator.

P.S My F1 Ferrari doesn't have a radiator fan - should I get one fitted?

zeupater

Cardew wrote: »

... P.S My F1 Ferrari doesn't have a radiator fan - should I get one fitted?

.... depends whether you're likely to be driving around town or not ... a bit like the early E-Types, woeful cooling leading to boiling the radiator every time you crawled around in traffic, but brilliant on the open road ....

Anyway, I agree .... I don't think anyone has taken the position that forcing air onto a convective radiator wouldn't increase it's efficiency, but the extra heat transferred to the air needs to be replaced by something, else logic would dictate that the increased efficiency would eventually cause the radiator to freeze .... :D ...

I wouldn't personally buy or build a system which in anyway restricted the natural passive convection as any system which does this would simply use a proportion of the forced airflow to replace the naturally occuring convective heat transfer, therefore underpowered units could logically reduce heat transfer ...

After a couple of days of unuse, we often use forced vertical airflow around/over our logburner using a fan blown ionizing air filtration unit in order to help warm the air as opposed to the mass of the surrounding masonry. However, when the air has been well mixed and is comfortably warm at a reasonable distance from the fireplace (normally the next room !) the unit is switched off and moved, leaving the thermal-mass to do it's job .... but that unit does consume more than a 0.5W fan, which would likely melt at the distance required to make any difference ...

HTH
Z

Mayen

Cardew wrote: »

The concensus is surely that it can only have a marginal effect(either way) on boiler efficiency by effectively having a bigger radiator.

The effectiveness is clearly going to depend on circumstance, but in my case with a new condensing boiler, old undersized radiators and uninsulated walls it was a neccessity to improve performance as rooms were uncomfortably cold.

Following previous advise to compensate by turning up the boiler temperature proved very costly, I had to turn back down on financial grounds alone, with these I`ve been able to reduce the boiler temperature by a further 5 degrees, yet at the same time achieve a comfortable environment. My previous experience (and others advise) indicates the boiler temperature reduction will save money.

zeupater wrote: »

I wouldn't personally buy or build a system which in anyway restricted the natural passive convection as any system which does this would simply use a proportion of the forced airflow to replace the naturally occuring convective heat transfer, therefore underpowered units could logically reduce heat transfer ...

I agree that is a concern, which is one reason I side mounted my units, which as I said does appear more effective.

I do note many trying (and overstating) their idea of a minimal effectiveness/saving but I've also not seen any provide proof of their thinking.

PS Before you say, wall insulation is not feasible.

PPS F1 cars are highly engineered and work at temperatures that are impractical elsewhere (engines are seized when cold), the comparison is illogical.

zeupater

Mayen wrote: »

I do note many trying (and overstating) their idea of a minimal effectiveness/saving but I've also not seen any provide proof of their thinking.

Hi

On the contrary, it seems that suppliers have products on the market which have little test-based data to support claims of either energy savings or efficiency increases.

The testing regime would be pretty simple. An environmentally controlled test room, a boiler, a radiator, metered energy supply and the ability to measure input & output flow temperatures relative to the room ambient, then simply test with & without the product ....

Many years ago I was involved in detailed product testing and performance analysis within a very similar setup in order to build heat transfer performance data models and algorithms used for product design and eventual evaluation to specification and therefore have a general idea of how much airflow is generated by heated surfaces .... it would be pretty easy for the manufacturers to perform a simple calculation based on the specific heat capacity of air and the tested btu rating of a radiator at 50C above ambient in order to quantify the rate of convection over the surface per unit time (cubic meters) and then establish how many cubic meters of additional airflow could be introduced by their devices in order to estimate potential effectiveness and create a performance curve based on radiator size & type (10/11/20/21/22) ..... but they don't !

HTH
Z

Mayen

zeupater wrote: »

On the contrary, it seems that suppliers have a products on the market which have little test-based data to support claims of either energy savings or efficiency increases.

Yes and I agree the radiator booster manufacturer does not seem to provide any convincing data, which is lax on their part, but their production seems also to indicate a lazy attitude (why is it so noisy?) it does seem a common attitude though, provide a cheap product at an inflated price at make out you doing everyone a favour!

Out of interest I recently did a comparison of kettle running costs as there is conflicting data about (I found gas hob kettle was cheapest but modern electric kettle most efficient) and in the process I found a induction hob manufacturer advertising comparatives that seemed totally unrealistic, when I queried their results their silence was deafening. :money:

Cardew

Mayen wrote: »

PPS F1 cars are highly engineered and work at temperatures that are impractical elsewhere (engines are seized when cold), the comparison is illogical.

Really?

Would the siezed engine account for my son having difficulty pedalling?

Ferrari Toy Pedal Car Racers - Zoom - Zoom!