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Old 10-01-2009, 01:04 PM   #8 (permalink)
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B*tch - '01 Honda Civic HX
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Originally Posted by rocket View Post
this is how A/C works in your car:

- The compressor increases the pressure (and temp) of the LP vapor (R-134a).
- It then goes to the condensor (the 'radiator' in front of the coolant radiator) where heat is removed (read temp dropped) until the R-134a condenses (still at or above ambiant temp). it is still at high pressure.
- the high pressure liquid then flows to the evaporator in the cab (usually under the dash or in a compartment in engine bay passenger side against the firewall)).
- in the evaporator, the R-134a aquires the 'latent heat of vaporization' from the ambiant air in the cab. this heat transfer cools the air flowing over the evaporator. this is when the R-134a gets cold (going from liquid to gas).
- the vapor then returns to the compressor.
You missed one critical element of an A/C system: the expansion valve (sometimes just an oriface). This valve is between the condensor and the evaporator and this is where the refridgerant transitions to low pressure and cools off in the process.

Before the expansion valve, you WANT it to dissapate heat, so it is not really helpful to add insulation. The ONLY part of the system that insulation would help is after the expansion valve and before the evaporator. I've seen this already in place on some newer cars, but a lot of manufaturers place the expansion valve so close to the evaporator that insulation is pointless.

2001 Civic HX Mods

Past Cars:

2003 Silverado Mods
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