Heaters over open shop doorways
Discussion
I am posting this here, because I know someone sciency will know the answer. I should point out I got a 'U' in my physics 'O' level, so please keep it a simple as possible please!
Why do shops, like Next, Dotty P's, etc put blow heaters facing downwards or horizontally over the wide open doorways of their shops?
I always thought heat rises, so heating the air at the top of the shop space is not going to help is it? Also, isn't there a huge amount of heat wasted by bleed to the outside colder air?
Tell me it's a logical thing to put a mahoosive blown air heater over an open doorway - and why, please! It's driven me mad since I was little.
Why do shops, like Next, Dotty P's, etc put blow heaters facing downwards or horizontally over the wide open doorways of their shops?
I always thought heat rises, so heating the air at the top of the shop space is not going to help is it? Also, isn't there a huge amount of heat wasted by bleed to the outside colder air?
Tell me it's a logical thing to put a mahoosive blown air heater over an open doorway - and why, please! It's driven me mad since I was little.
Behavioural rather than science related for the large part - it's for the same reason they put AC over them in the summer (in some places). It provides an instant 'ahh' to a significant percentage of the footfall upon entry, and highlights the miserable weather outside when you leave. If your first and last experience of the store is an almost instant, increased comfort level (or leaving decreases your comfort level) you typically stay longer, spend more, and are more inclined to return.
Also, if they went upwards, it'd be altogether more entertaining for the chaps, miserable for women in skirts, and it wouldn't form a barrier, it'd be dispersed.
Also, if they went upwards, it'd be altogether more entertaining for the chaps, miserable for women in skirts, and it wouldn't form a barrier, it'd be dispersed.
Edited by Stu R on Friday 9th November 14:05
Tyre Smoke said:
GWC said:
They are called air curtains and are designed to create a barrier between inside and out keeping the cost of heating the building down.
How?Stu, see what you are saying, but it's surely a ruinously expensive way of keeping your shoppers inside?
Stu R said:
Tyre Smoke said:
GWC said:
They are called air curtains and are designed to create a barrier between inside and out keeping the cost of heating the building down.
How?Stu, see what you are saying, but it's surely a ruinously expensive way of keeping your shoppers inside?
mrmr96 said:
Stu R said:
That's not their main purpose, as said it's a barrier from the elements. Retail stores consume a ton of energy, another 10-15kw on for all that benefit isn't much really.
Surely the air stream from the roof hits the floor and then will "splash" with half going outside, and the other half going inside? So any warm air on the inside of the air stream will tend to be returned inside. And likewise cold air on the outside will be driven down by the stream, but then "splash" back outside once the stream hits the floor?Munter said:
mrmr96 said:
Stu R said:
That's not their main purpose, as said it's a barrier from the elements. Retail stores consume a ton of energy, another 10-15kw on for all that benefit isn't much really.
Surely the air stream from the roof hits the floor and then will "splash" with half going outside, and the other half going inside? So any warm air on the inside of the air stream will tend to be returned inside. And likewise cold air on the outside will be driven down by the stream, but then "splash" back outside once the stream hits the floor?I think it's the same principle as my cunning plan to heat only the cavity in the walls of a house. With the cavity maintained at a certain temperature, the interior cannot drop below it... yes you lose heat through the wall, but the volume of air to heat is a tiny fraction of the house.
Simpo Two said:
I think it's the same principle as my cunning plan to heat only the cavity in the walls of a house. With the cavity maintained at a certain temperature, the interior cannot drop below it... yes you lose heat through the wall, but the volume of air to heat is a tiny fraction of the house.
Not sure if serious?mrmr96 said:
Not sure if serious?
If I was any good at physics I might see whether it's cheaper to keep X volume of air at (say) 19C with a faster heat loss than 1000X volume at 19C with a slower heat loss. If you have a box surrounded by a constant 'jacket' at 19C, the interior of the box cannot cool down.They all laughed when Edison invented sound you know...
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