Add another 'don't do it'. The control valve in a 134a V5 is different from the R12 unit. Pressure points are different. Any temp change as a result from the 12 would or could be negated by the control valve. Since 134a tends to be operational more efficient than 12 in a system designed for the refrigerant, a suggestion would be to perhaps have the system serviced. Once more how low does one expect an A/C to cool.
Saw a post wishing for 'frost' from the vents....only problem the human body will not tolerate these temps for an extended period of time...so....then temp controls are adjusted...and the result...a low 40's temp. Boggles the mind.
If not mistaken...it is an illegal act to introduce R12 into a 134a system...will check with EPA to find the ruling.
Good luck!!!

Follow Ups:

• Re: r-12 jackca 4/19/2005 (2)
  • You should feel free to ask questions here Tom Greenleaf 4/20/2005 (0)
  • Re: r-12 Chick 4/19/2005 (0)
• Re: r-12 jackca 4/19/2005 (0)
• Re: r-12 jackca 4/19/2005 (0)
• Re: r-12 jackca 4/19/2005 (0)
• Re: r-12 Chick 4/19/2005 (0)