986 Forum - The Community for Porsche Boxster & Cayman Owners - View Single Post - Still Chasing AC Problem

thom4782 · 03-01-2013, 06:27 PM

Thanks for the suggestions so far.

The noise isn't radio related. It's there whether or not the radio is on.

I'll double whether it comes from one of the condensers. I might be surprised. The sound however seems like it coming from the area under the expansion value / pollen filter. I suppose it could be the evaporator.

Two follow-on questions if the sound is coming from the condenser or the evaporator, hyw would one of these components make a whining sound? Why would it change with engine speed? I could guess the answer to the second question -- the refrigerant pressure and flow rate increases as the compressor speed increases. If the noise is flow related, the its pitch could be higher with greater flow rates.

03-01-2013, 06:27 PM	#4
thom4782 Registered User Join Date: Sep 2010 Location: Foster City CA Posts: 1,099	Thanks for the suggestions so far. The noise isn't radio related. It's there whether or not the radio is on. I'll double whether it comes from one of the condensers. I might be surprised. The sound however seems like it coming from the area under the expansion value / pollen filter. I suppose it could be the evaporator. Two follow-on questions if the sound is coming from the condenser or the evaporator, hyw would one of these components make a whining sound? Why would it change with engine speed? I could guess the answer to the second question -- the refrigerant pressure and flow rate increases as the compressor speed increases. If the noise is flow related, the its pitch could be higher with greater flow rates. Last edited by thom4782; 03-01-2013 at 06:29 PM.