De'longhi TRD4 1025T Dragon 4 Oil Filled Radiator with Timer, 2.5 KW - White £79.99 Dispatched from and sold by Hughes Direct @ Amazon
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De'longhi TRD4 1025T Dragon 4 Oil Filled Radiator with Timer, 2.5 KW - White £79.99 Dispatched from and sold by Hughes Direct @ Amazon

61
Found 10th Feb
  • The enhanced chimney effect accelerates hot air through vents for effective heating
  • 2.5 kW heat output and three heat settings
  • Elegant design and pure brilliant white finish
  • Pre-assembled easy wheels and carry handle for easy transportation
  • 10 year manufacturer's warranty
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61 Comments
What kW should I use for a room about 19sqm
snappyfish2 m ago

What kW should I use for a room about 19sqm


This should be enough to maintain a comfortable temp.
Quality the fins really do make a massive difference imho
patrickpldj1 h, 35 m ago

Quality the fins really do make a massive difference imho


Given that all electric heaters work at 100% efficiency, how can the fins make a difference? Except when swimming, of course.
emlin29 m ago

Given that all electric heaters work at 100% efficiency, how can the fins …Given that all electric heaters work at 100% efficiency, how can the fins make a difference? Except when swimming, of course.

Yes you are right, all heaters are exactly the same lol🤣
Convection currents, surface area and design mean nothing in the efficiency of dispersing heat just the wattage?
I don't think so.
Edited by: "Seeya" 10th Feb
patrickpldj24 m ago

Yes you are right, all heaters are exactly the same lol🤣Convection …Yes you are right, all heaters are exactly the same lol🤣Convection currents, surface area and design mean nothing in the efficiency of dispersing heat just the wattage?I don't think so.


Same heat, bro. There ain't no way around it. It's physics and you should get to know it.
Edited by: "emlin" 10th Feb
emlin1 h, 21 m ago

Same heat, bro. There ain't no way around it. It's physics and you should …Same heat, bro. There ain't no way around it. It's physics and you should get to know it.


Not the same heat, bro
Its surface area that determines the maximum heat output capacity of a radiator. The larger the surface area, the higher the potential heat output. Surface area will be greatly increased by convectors, fins, or double or triple panels. So for example, the heat output capacity of a flat single panel radiator will be considerably less than a radiator of the same size (height x width) with double panels, and/or convectors or fins. When considering one model of radiator, then generally, the bigger the radiator, the bigger the heat output. However this is not necessarily the case when comparing one model of radiator against another- for example steel against aluminium, or number of radiating fins.
patrickpldj43 m ago

Not the same heat, bro Its surface area that determines the maximum heat …Not the same heat, bro Its surface area that determines the maximum heat output capacity of a radiator. The larger the surface area, the higher the potential heat output. Surface area will be greatly increased by convectors, fins, or double or triple panels. So for example, the heat output capacity of a flat single panel radiator will be considerably less than a radiator of the same size (height x width) with double panels, and/or convectors or fins. When considering one model of radiator, then generally, the bigger the radiator, the bigger the heat output. However this is not necessarily the case when comparing one model of radiator against another- for example steel against aluminium, or number of radiating fins.


Sorry, but that is rubbish. All the wattage (power) that goes into the heater will be emitted as heat. The deployment of fins doesn't come into it. You can't defeat the laws of physics with words, no matter how many you employ.
Edited by: "emlin" 10th Feb
Just to add to the above discussion, this is oil-filled and stays hot for a long while after bringing the room up to the programmed temperature and cutting out.

If used correctly, it'll be considerably more efficient (over time) than a cheap convector or blow heater since they do not retain heat after cutting out. It'll also provide a much more even feel to the room temperature.

Great heaters these.
emlin2 h, 35 m ago

Sorry, but that is rubbish. All the wattage (power) that goes into the …Sorry, but that is rubbish. All the wattage (power) that goes into the heater will be emitted as heat. The deployment of fins doesn't come into it. You can't defeat the laws of physics with words, no matter how many you employ.


Not really... kinda... but not.

1) the heat from the heater will transfer to the air in the room by convection. This is easier to do if there's more air flow - typically done using fins (so more air can flow around the heater).

2) you're talking about the efficiency of using electricity to heat the heater. Yes - if your aim is to have a piping hot heater then a 2.5kwh heater will heat up just like any other 2.5kwh heater*. However, most people want that heat to transfer to the air in the room. See point 1. So the rest of us are talking about efficiency in terms of how long it takes for the heat to transfer from the heater to the room the room.

[* just wanted to throw in that the thermostat on the housing of the heater means it will stop using electricity when it hits the 'desired' temperature. Because of the above, the thermostat hitting desired temperature doesn't necessarily mean the air in the room is at that temperature!)
rumble25 m ago

Just to add to the above discussion, this is oil-filled and stays hot for …Just to add to the above discussion, this is oil-filled and stays hot for a long while after bringing the room up to the programmed temperature and cutting out.If used correctly, it'll be considerably more efficient (over time) than a cheap convector or blow heater since they do not retain heat after cutting out. It'll also provide a much more even feel to the room temperature.Great heaters these.


Wrong again, sorry. Watts in will equal watts out. Always. All electric heaters have 100% efficiency. Full stop.
Edited by: "emlin" 10th Feb
emlin11 m ago

Wrong again, sorry. Watts in will equals watts out. Always. All electric …Wrong again, sorry. Watts in will equals watts out. Always. All electric heaters have 100% efficiency. Full stop.


I'm not wrong, because I'm not disputing the laws of physics.

The oil inside a good quality oil-filled radiator, once it is heated, remains hot for a considerable period of time after it has stopped consuming electricity. So the radiator continues to produce heat long after it's stopped using electricity....standard convector and blow heaters cannot do this and therefore have to be on longer (over a period of time) to maintain the same temperature.

Laws of physics and thermodynamics fully applied.
rumble16 m ago

I'm not wrong, because I'm not disputing the laws of physics.The oil …I'm not wrong, because I'm not disputing the laws of physics.The oil inside a good quality oil-filled radiator, once it is heated, remains hot for a considerable period of time after it has stopped consuming electricity. So the radiator continues to produce heat long after it's stopped using electricity....standard convector and blow heaters cannot do this and therefore have to be on longer (over a period of time) to maintain the same temperature.Laws of physics and thermodynamics fully applied.


You said it'll be considerably more efficient (over time).


No it won't. With an oil filled radiator, while it'll just take longer to heat up, it will longer to cool down. But that's not what you said, you said that it would be more efficient, which it most certainly is not. You can't buck the laws of thermodyamics. So don't demean yourself by trying.
Edited by: "emlin" 10th Feb
emlin9 m ago

You said it'll be considerably more efficient (over time).No it won't. …You said it'll be considerably more efficient (over time).No it won't. With an oil filled radiator, while it'll just take longer to heat up, it will longer to cool down. But that's not what you said, you said that it would be more efficient, which it most certainly is not. You can't buck the laws of thermodyamics.


It is more efficient because the oil retains heat for a long period of time. This heater takes about 5 mins longer to heat up than a convector heater (I know, we've got both) but emits heat for hours after it stops consuming electricity....the convector heater cannot do this. Much more heat is produced for the SAME AMOUNT of energy used.

Much, much more efficient over a period of time and more level room temperatures. No doubt whatsoever either scientifically or real-world testing.

The same principle is why heat-retaining bricks where placed in old-fashioned storage heaters and why hybrid cars consume less fuel per mile.
So much confusion and oversimplification about heater efficiency... Here's the truth: all electric heaters are technically 100% efficient, but "real life" efficiency depends on what you use it for.

Example 1: Bob has a garden shed where he sometimes escapes to so he can solder stuff and listen to 70s music. His shed is cold, so he wants a heater that will warm it up quickly and when he's finished in there, he doesn't care if it stays warm or not.
Solution: the most efficient heater for Bob is one that warms up quickly (either a high power heater or one with low mass - a light one) and one that cools down quickly so we wastes minimal heat when he's finished (again a light heater). So Bob should get a fan or radiant heater (convection would be ok too).

Example 2: Bill's central heating is a bit crap and doesn't keep his draughty living room warm. He wants a heater that steadily warms the room and is quiet, not one that clicks on and off every 15 mins on a thermostat. His dog sleeps in the living room, so he also wants the warmth to stay after he goes to bed.
Solution: Bill would like an oil filled heater. But it's not more efficient than other types, it just fits his needs better.
ted20911 m ago

So much confusion and oversimplification about heater efficiency... Here's …So much confusion and oversimplification about heater efficiency... Here's the truth: all electric heaters are technically 100% efficient, but "real life" efficiency depends on what you use it for.Example 1: Bob has a garden shed where he sometimes escapes to so he can solder stuff and listen to 70s music. His shed is cold, so he wants a heater that will warm it up quickly and when he's finished in there, he doesn't care if it stays warm or not.Solution: the most efficient heater for Bob is one that warms up quickly (either a high power heater or one with low mass - a light one) and one that cools down quickly so we wastes minimal heat when he's finished (again a light heater). So Bob should get a fan or radiant heater (convection would be ok too).Example 2: Bill's central heating is a bit crap and doesn't keep his draughty living room warm. He wants a heater that steadily warms the room and is quiet, not one that clicks on and off every 15 mins on a thermostat. His dog sleeps in the living room, so he also wants the warmth to stay after he goes to bed.Solution: Bill would like an oil filled heater. But it's not more efficient than other types, it just fits his needs better.


What have noises to do with thermal efficency, apart from the fact that they will have 100% thermal efficiency?
Edited by: "emlin" 10th Feb
You lot are cute... but, all wrong.
rumble13 m ago

It is more efficient because the oil retains heat for a long period of …It is more efficient because the oil retains heat for a long period of time. This heater takes about 5 mins longer to heat up than a convector heater (I know, we've got both) but emits heat for hours after it stops consuming electricity....the convector heater cannot do this. Much more heat is produced for the SAME AMOUNT of energy used.Much, much more efficient over a period of time and more level room temperatures. No doubt whatsoever either scientifically or real-world testing.The same principle is why heat-retaining bricks where placed in old-fashioned storage heaters and why hybrid cars consume less fuel per mile.


Once you have got your head around the meaning of the word "efficiency" you will be qualified to comment.
rich_19861 m ago

You lot are cute... but, all wrong.


Yeah, that helped.
emlin1 m ago

Once you have got your head around the meaning of the word "efficiency" …Once you have got your head around the meaning of the word "efficiency" you will be qualified to comment.


efficient
ɪˈfɪʃ(ə)nt/
adjective

1.
(of a system or machine) achieving maximum productivity with minimum wasted effort or expense.
emlin5 m ago

What have noises to do with thermal efficency, apart from the fact that …What have noises to do with thermal efficency, apart from the fact that the will have 100% thermal efficiency?


Nothing - it's just why someone might reasonably choose on of these oil filled radiators. Nothing to do with efficiency.
emlin4 m ago

Yeah, that helped.


You’re welcome.
rumble4 m ago

efficientɪˈfɪʃ(ə)nt/adjective1.(of a system or machine) achieving maximum p …efficientɪˈfɪʃ(ə)nt/adjective1.(of a system or machine) achieving maximum productivity with minimum wasted effort or expense.


I am well aware of the meaning of the word. Don't even try to condescend. All electric heaters have 100% efficency. Just google it for eff's sake!
ted2098 m ago

Nothing - it's just why someone might reasonably choose on of these oil …Nothing - it's just why someone might reasonably choose on of these oil filled radiators. Nothing to do with efficiency.


Looks?
emlin14 m ago

I am well aware of the meaning of the word. Don't even try to condescend. …I am well aware of the meaning of the word. Don't even try to condescend. All electric heaters have 100% efficency. Just google it for eff's sake!


You asked me to 'get my head round the meaning of a word' then accuse me of the above?

Efficiency includes expense.

A standard room in my mum's old house will keep a steady temperature with about 5 hours use of the above radiator across a 24hr period. The convector heater (same KW) would have to be on most of the time to do the same...I'd say about 18hrs.

5hrs consumption v 18hrs consumption for the same result = one product being way more efficient than the other.

Now, there are cases where someone will want just a quick blast of heat for a short period of time and that's when (as ted pointed out) a blow heater or somesuch might win out, but most people will be looking to heat rooms over a period of time.
I don't care about your anecdotes. Do you think that they trump the laws of physics?

I can agree that different forms of heating may suit some people rather than others, however that does not and cannot (with electric heating) make them more efficient. More "snuggly" in use sometimes, perhaps. But both you and I know that that was not what we were talking about as we both were referring to efficiency. Or were you using the term wrongly?
Edited by: "emlin" 10th Feb
im confused will all these comments and all i can offer is what i pay in electric .....if i have my 1Kw convector heater on for an HOUR it cost the same as my 1Kw oil filled radiator .... the diffrerence is the oil filled one stays hotter for much much longer after it has been turned off so in effect it is much more efficient/economical than the convector heater of the same wattage .im only speaking from what i actually pay as i have no science to back up my opinions
emlin6 m ago

I don't care about your anecdotes. Do you think that they trump the laws …I don't care about your anecdotes. Do you think that they trump the laws of physics?I can agree that different forms of heating may suit some people rather than others, however that does not and cannot (with electric heating) make them more efficient. More "snuggly" in use sometimes, perhaps. But both you and I know that that was not what what we were talking about as we both were referring to efficiency. Or were you using the term wrongly?


I was using the term as per the definition posted (that's why I posted it!).

Efficiency includes expense and physics doesn't stop applying when the electricity is turned off. Materials that retain heat continue emitting it at no expense.
The d
cadmus4 m ago

im confused will all these comments and all i can offer is what i pay in …im confused will all these comments and all i can offer is what i pay in electric .....if i have my 1Kw convector heater on for an HOUR it cost the same as my 1Kw oil filled radiator .... the diffrerence is the oil filled one stays hotter for much much longer after it has been turned off so in effect it is much more efficient/economical than the convector heater of the same wattage .im only speaking from what i actually pay as i have no science to back up my opinions


The difference is that the heater you have takes longer to heat up. It is impossible that you could be paying less on the same plan but be getting more heat.
I do know the science.
cadmus4 m ago

im confused will all these comments and all i can offer is what i pay in …im confused will all these comments and all i can offer is what i pay in electric .....if i have my 1Kw convector heater on for an HOUR it cost the same as my 1Kw oil filled radiator .... the diffrerence is the oil filled one stays hotter for much much longer after it has been turned off so in effect it is much more efficient/economical than the convector heater of the same wattage .im only speaking from what i actually pay as i have no science to back up my opinions


Thank you.....and don't worry your real world testing is backed up by science.
rumble5 m ago

Thank you.....and don't worry your real world testing is backed up by …Thank you.....and don't worry your real world testing is backed up by science.


Unfortunately, there was no science in your reply, unless the laws of thermodynamics are all wrong, which the aren't.
Edited by: "emlin" 10th Feb
emlin3 m ago

The d The difference is that the heater you have takes longer to heat up. …The d The difference is that the heater you have takes longer to heat up. It is impossible that you could be paying less on the same plan but be getting more heat. I do know the science.


It takes about 10/15 minutes to get fully hot and stays hot for hours after it stops consuming electricity.

I'm only speaking about this particular radiator, other oil-filled radiators may differ.

Without any shadow of a doubt it's cheaper (much cheaper) at heating a room over longer periods.
rumble8 m ago

I was using the term as per the definition posted (that's why I posted …I was using the term as per the definition posted (that's why I posted it!).Efficiency includes expense and physics doesn't stop applying when the electricity is turned off. Materials that retain heat continue emitting it at no expense.


I guess the argument would be that the first lot of energy was used to heat the fins before the air.

Having said that..I have used various electrical heaters in the home and greenhouse and to achieve the same heat it has always cost me less with oil filled radiators.

I am aware of the science that all electrical heaters are 100 percent efficient, so presumably there is something else at play here. But.. There really is a difference.
Edited by: "pipehippy" 10th Feb
rumble5 m ago

It takes about 10/15 minutes to get fully hot and stays hot for hours …It takes about 10/15 minutes to get fully hot and stays hot for hours after it stops consuming electricity.I'm only speaking about this particular radiator, other oil-filled radiators may differ.Without any shadow of a doubt it's cheaper (much cheaper) at heating a room over longer periods.


And how much does it cost you to get up to what you think is an acceptable temperature. And why do you think that you are getting free energy when the rest of us are not?
pipehippy7 m ago

I guess the argument would be that the first lot of energy was used to …I guess the argument would be that the first lot of energy was used to heat the fins before the air.Having said that..I have used various electrical heaters in the home and greenhouse and to achieve the same heat it has always cost me less with oil filled radiators.I am aware of the science that all electrical heaters are 100 percent efficient, so presumably there is something else at play here. But.. There really is a difference.


No. There is no difference. Show me your bills correlated to the outside temperature and I will show you that your "gains" are imaginary.
emlin14 m ago

Unfortunately, there was no science in your reply.


It takes about 15 mins longer to get the room up to temperature than the convector heater does......but emits heat for hours after it stops consuming electricity.

It's not free energy....it's energy retention.


emlin14 m ago

Unfortunately, there was no science in your reply.

emlin11 m ago

No. There is no difference. Show me your bills correlated to the outside …No. There is no difference. Show me your bills correlated to the outside temperature and I will show you that your "gains" are imaginary.


You're too fixated on the conversion. What about draughts from the fan heater? Even if you plug it into a thermostat to try and regulate the temperature you will still notice the cold as the heater clicks off, where the radiator provides a constant, even heat. Do the fins help keep the heat in the room longer?

As I said I understand the principal of the conversion being the same, but there's more to it than that.
Edited by: "pipehippy" 10th Feb
rumble3 m ago

It takes about 15 mins longer to get the room up to temperature than the …It takes about 15 mins longer to get the room up to temperature than the convector heater does......but emits heat for hours after it stops consuming electricity. It's not free energy....it's energy retention.


And where does the "retention" come from? You've paid for that energy while you were heating the thing up! It don't come free you know.
emlin7 m ago

And where does the "retention" come from? You've paid for that energy …And where does the "retention" come from? You've paid for that energy while you were heating the thing up! It don't come free you know.


Some materials retain heat well (like oil inside a metal radiator), others don't.....(like elements in a blow/convection heater or the thin metal casing).
pipehippy10 m ago

Your too fixated on the conversion. What about draughts from the fan …Your too fixated on the conversion. What about draughts from the fan heater? Even if you plug it into a thermostat to try and regulate the temperature you will still notice the cold as the heater clicks off, where the radiator provides a constant, even heat. Do the fins help keep the heat in the room longer?As I said I understand the principal of the conversion being the same, but there's more to it than that.


You say that there is "more to it than that," But mystics will say the same, and they are charlatans, every one of them.

What problem do you have with the laws of physics?. And if you do have problems with the laws of physics, why aren't you in constant terror that the moon might decide, willy-nilly, to fall on us?
Edited by: "emlin" 10th Feb
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