On Sun, 10 Nov 2013 16:53:46 +0000 (UTC),
(Andrew Gabriel) wrote:

In article ,
mogga writes:

How many fin things do they have?

There's a number coding something like
11 - having one panel and one fin
12 one panel and 2 fins

Never seen one of those!

21 having two panels and one fin
22 two panels and 2 fins.

Four of mine have 3 panels 3 fins.

They might not be called fins.. but you know the things I mean.

However the fins are arranged, the unit that stands taller will not
radiate heat as efficiently. By the time the convection current
carries the air from bottom to the top of the radiator, it will hotter
than that of the wider, lower unit. So assuming that the surface area
including fins is the same, then the heat tranfer would be limited by
the reduced temperature gradient as the increasingly warmer air
ascends.

AB