Power to drive R134 Freon compressor

[thruthefence]

Can someone estimate the power required to drive a modern, everyday automobile air conditioner compressor, R134, assuming a 90 degree F ambient temperature. Ball Park figures welcomed.

thanks

 

[MikeHalloran]

I'm guessing not more than five HP; the typical compressor can still be driven with a single narrow v-belt.



Mike Halloran
Pembroke Pines, FL, USA

 

[MiketheEngineer]

That is about the same as I have always heard

 

[thruthefence]

Thanks, Guys!!

steve

 

[Metalguy]

I think it can easily go up to 10 or 15, depending on the temp. On hot days here in Arizona, I can feel a car or truck slow down a bit when the compressor engages, on systems where the clutch cycles.

Given the 5" or so pulley sizes, that much HP can easily be transmitted by a single v-belt at the RPM involved.

"You see, wire telegraph is like a very long cat. You pull his tail in New York and his head is meowing in Los Angeles. Do you understand this? Radio operates the same way: You send signals here, they receive them there. The only difference is there is no cat." A. Einstein

 

[rmw]

You might want to ask the question on the HVAC/R Forum. Those guys live with this stuff every day.

Otherwise, it is a matter of doing some research to see if you can determine the "average" tonnage that your "everyday" car requires and then do the thermodynamic calculations along with some reasonable assumptions about compressor efficiency, etc.

That is my tip - I don't do math on this site (do that for my day job.)

rmw

 

[patprimmer]

The capacity of the drive belt on other similar systems gives a very good gauge I would think.

Regards
Pat
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[rmw]

Most engines that I am familiar with these days have a single belt. So it would have to be sized to do it all.

rmw

 

[bentwings1]

I just finished installing AC on my streetrod. 500+ hp 6-71 blown SBC. If the AC takes 5 hp who cares as long as it is cool when the air temp is hot and it's hot when the air temp is cool. haha

5 hp is way more than the Sanden 508 takes from what the AC people say. A single 3/8 belt lasts forever if it is tensioned right and in alignment with the pulleys.

99 Dodge CTD dually.

 

[thruthefence]

How much is "way more", according to the "air conditioner guys"

 

[chicopee]

Remember the rule of thumb about AC's and that is about 20-25 dF differential between occupant space and ambient temperature.There will be also some additional cooling requirement to lower RH within the oocupant space.

 

[Gearloose1]

For a standard AC in a mid sized car, 3hp and up, for a full size or truck, 5 and up.

That is, for the time it is actually running.

Note the comment about heating load of a typical car in winter below...

http://macsworldwide.wordpress.com/2011/01/21/gm-speaks-—-volt’s-got-heat/

 

[thruthefence]

Here is an electrically driven freon compressor, 12-24V.
Anyone have any experience with this system?

http://www.revoltevc.com/climate/cooling/compressor/sierra-01-compressor.html

 

[RossABQ]

Sanden publishes curves including power input requirements:

http://www.sanden.com/index.php?tag=LZYYCH9G2

Not clear to me what the units on the left axis are...

 

[GregLocock]

kW, pity they don't test at higher speeds.

Cheers

Greg Locock


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