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zlobster
21-11-2012, 04:02 PM
Hiya,

Here is a newb question for the people with technical knowledge on the matter.

Does the weight of external inverter split type AC (typical home AC for moderate climate) body affects the cooling/heating performance of the system? I mean, if the external body weights let's say 25kg, will it cool/heat less than a 35kg one if both are rated for 9000Btu?

Are there such materials and designs that would compensate for the weight and/or any other factors (quotients, etc.)?

Thanks in advance!

frank
21-11-2012, 08:04 PM
The transfer of heat is all about Thermodynamics.....not weight (Mass)

zlobster
21-11-2012, 10:46 PM
The transfer of heat is all about Thermodynamics.....not weight (Mass)


Hi frank,

Thank you for your quick response. Care to elaborate with some lame examples? As I mentioned I'm a n00b in Thermodynamics and related topics. Well, tbh I'm somewhat familiar with some basic concepts but nothing serious.

I just hate when people say 'This X suxz big time because the external body weights 10kg less than Y!'

Could someone please bring some theory to help me put this thing right (and sleep a tad better at night:)), please? Even some math will do.

TIA!

Brian_UK
21-11-2012, 11:15 PM
The weight difference could be due to the type of materials used, or the thickness of the metal casings so no real significance should be attached to the actual weight of the unit.

eggs
21-11-2012, 11:16 PM
Hiya,

Does the weight of external inverter split type AC (typical home AC for moderate climate) body affects the cooling/heating performance of the system? I mean, if the external body weights let's say 25kg, will it cool/heat less than a 35kg one if both are rated for 9000Btu?


Well, to begin with I once dropped a 25kg condensing unit on my toe.....it hurt like feck. Then 3 days later I dropped a 75kg condensing unit on the same toe.......trust me to be wearing trainers again.....It hurt a whole lot feckin' more.......and a whole lot more hot air and expletives exited my mouth.

So my theory is that if I hadn't dropped this heavier condensing unit on my toe, all the resulting hot air wouldn't have exited my mouth and there would be no difference in performance due to weight between the two condensing units.
There may have momentarily been a slight increase in the COP of the heavy unit as it hit my toe because the ambient temperature was 9 deg C and as I yelped I thing my breath was at about 36.....ish..

frank
22-11-2012, 11:45 AM
Your original question states that the unit is rated at 9000BTU's. This is a measure of the thermal capacity of the unit i.e. it can add or remove 9000BTU's. (heat energy)

The parts that make up the system are sized mechanically to achieve this duty. As Brian says, the weight of the materials used to manufacture the unit don't have any bearing on the unit's ability to achieve it's duty.

And Eggs needs Santa to bring him some steel toe'd trainers :D

hookster
22-11-2012, 05:11 PM
I would take the heavier unit as a matter of choice!
Possibility is that manufacturer has oversized outside unit to cater for larger indoor unit range and to cut down manufacturing cost with smaller component range (Lean manufacturing principles).

If it fails this also then gives you a higher weigh in value! ;)