Questions about A/C vacuuming

[George Selby]

At 02:19 PM 6/7/04 -0400, you wrote:
>You may see 25" vac with the venturi vacuum if you're lucky.
>Your results will be better if you get the engine compartment as warm as
>possible


I have the same Harbor Freight vacuum puller.

The most I could pull with mine was about 25" of vacuum.  The stronger air 
compressor you have, the better it will work.  (I have a portable unit, 
around 5 scfm/90 psi, and it can hardly do the job.  I have a friend with a 
industrial compressor with a huge tank, and his compressor actually shuts 
on and off while it's trying to pull vacuum.  Remember while pulling vacuum 
you are essentially leaving the air line wide open.)

I would also recommend using a moisture trap on the air line from the 
compressor.  Without it, water forms around the venturi and interferes with 
the vacuuming process.

My recommendation would be to use the puller you have to verify you have no 
leaks, and then let a professional shop do the final pull, and insertion of 
the new refrigerant.

George Selby