# Forum Home Renovation Heating & Cooling  what is the horse power rating of my aircon??

## wozzzzza

i have a wall mounted airconditioner that says on the label cooling capacity 4600W and heating 4200W.  people are asking me how many horse power this is, i have absolutely no idea, how do i find out??  what is the conversion??  is there a conversion?

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## rrobor

746 watts = 1 horse power so geet your calculator out.

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## exotiic

The 746 watts = 1HP regards the electrical input rating not the output. The 4600W cooling and 4200W heating is the output of the unit. You have to find the electrical input to use that conversion which should be on that same rating plate.

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## wozzzzza

> The 746 watts = 1HP regards the electrical input rating not the output. The 4600W cooling and 4200W heating is the output of the unit. You have to find the electrical input to use that conversion which should be on that same rating plate.

  only things its got is cooling 4600W 7.9A, heating 4200W 5.8A, 240V and model number, thats it.
no other labels anywhere.

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## Bedford

> only things its got is cooling 4600W 7.9A, heating 4200W 5.8A, 240V and model number, thats it.
> no other labels anywhere.

  I calculates it at 2.54 HP cooling and 1.86 heating....via ohms law. :Smilie:

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## Smurf

Assuming it's of average efficiency (1 unit of power in = 3 units of heat moved) then the compressor size is very close to (or exactly) 2 horse power. 
4400 Watts output / 3 = 1467 W input  
1467 / 746 = 1.97 horese power

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## Gooner

Best way to find out is to stand in front in front of the unit naked. Take your body temperature with the unit off. For accuracy reasons, this has to be done rectally. Then turn the unit on full blast and stand in front of it for 20 minutes. Take your body temperature again (rectally). The difference in body temperature (in deg C) multiplied by 12.86 is you cooling rating in HP. 
Do the same for heating. 
Note: There is another very similar method based on genitalia shrinkage rates, but this method has been found to be less accurate and therefore is seldom used anymore within the profession.

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## rrobor

Must admit to confusion here,   Horse power as I see it is work done, as are Watts. I was under the odd illusion, or delusion, that heat was measured in BTU.  IE thermal units or as Gooner states, shrinkage of gonads. Now I do realise horses are prone to expel hot air, but I didnt realise this was a quantifiable commodity measured in Watts.

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## GraemeCook

Bedford's calculation is mathematically correct, but why bother.   Horsepower is an antique measure. 
Its almost as silly as the Americans measuring heat pump capacity in tons (of ice it can freeze or melt ! ) 
What is important is how much heat (or cold) it produces and its efficiency. 
Anyway, who now uses horses to heat their homes! 
Cheers 
Graeme

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## Bedford

> Horsepower is an antique measure.

  I agree, but atleast he knows how many Hp it is, but it's not much help if we don't know how big the horse is! :Biggrin:

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## Master Splinter

But a burning horse puts out plenty of heat!  It's just a bugger that you have to prime them with a good slosh of petrol to get them started!

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## wozzzzza

ok its somewhere between 2-2.5HP, thats good enough for me thanks.

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## elkangorito

> only things its got is cooling 4600W 7.9A, heating 4200W 5.8A, 240V and model number, thats it.
> no other labels anywhere.

  Assuming 230v single phase & using the cooling cycle only: 
P = E x I x P.F. (P.F. is power factor - for a motor, I've assumed 0.8)
P = 230 x 7.9 x 0.8
P = 1.45kW (electrical). 
1450W divided by 746 = 1.94 Horsepower (round up to 2 HP). 
As somebody else said, nobody except the yanks use antiquated units of measurement. Kilowatts is the way to go.

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