AC Repair Question

[brycraft]

I have a question regarding a 5 year old American Standard Allegiance 10 Central air unit. It is the 2 ton model. My sister in law just moved into her home and found the a/c was blowing warm air so a repair person came out and cerviced the unit with freon and told her he repaired a leak but couldn't guarantee it would last, charge $300, well it didn't hold and he came back, charge her another $50 and told her she needed a "NEW SERVICE VALVE ON THE CONDENSOR" that he couldn't repair it and it needed replacement cost about $600 because it is in a difficult location because of lines and what not. First does this sound reasonable? second can a non service person purchase this part on his own (like myself)? and where could I locate this part? I am a licensed aircraft mechanic with a high degree of mechanical aptitude and if this is somthing that can be done I would rather do it myself then have her pay more money that she can't afford. If it came to it is she throwing money away at this particular unit and should she consider a whole new unit like an Amana or Carrier?
Thanks for all your help

[albright]

A/c Leak

[b]i Dont Believe That Price And Reasoning. If It Is The Service Vavle Leaking Than He/she Could Just Replace The Shrader Vavle With Out Any Difficulty. Now If There Is A Leak In The Metal, In Or Around The Valve. It Would Be Difficult To Get To It With A Torch And Brazing Rod To Fill The Leak. If He/she Would Have To Braze Then They Would Have To Vacuum Down Your System And A Filter Dryer And Recharge Your System. At The Most With Having To Do All Of Those Steps I Just Mentioned Would Not Take More Than 2 Hours.

[lonestarheir]

I have a question regarding a 5 year old American Standard Allegiance 10 Central air unit. It is the 2 ton model. My sister in law just moved into her home and found the a/c was blowing warm air so a repair person came out and cerviced the unit with freon and told her he repaired a leak but couldn't guarantee it would last, charge $300, well it didn't hold and he came back, charge her another $50 and told her she needed a "NEW SERVICE VALVE ON THE CONDENSOR" that he couldn't repair it and it needed replacement cost about $600 because it is in a difficult location because of lines and what not. First does this sound reasonable? second can a non service person purchase this part on his own (like myself)? and where could I locate this part? I am a licensed aircraft mechanic with a high degree of mechanical aptitude and if this is somthing that can be done I would rather do it myself then have her pay more money that she can't afford. If it came to it is she throwing money away at this particular unit and should she consider a whole new unit like an Amana or Carrier?
Thanks for all your help

1. How can you check the a/c it is cold there right now, isn't it? Can't really check an a/c system below 75-77 degrees outside temperature.

2. Did the first tech show where the leak was before, and where the new one is?

3. Why did they pay another $50 to find out something that should have been found the first time?

4. Even with mechanical aptitude without the proper equipment replacing a service valve is not something that should be attempted. You will need a recovery maching, oxy/acty rig, vacuum pump, refrigerant, guages, and various other specialty tools. For a pro to do it correctly should take about 2-3 hours (tech mostly sitting and watching while the machines do their job to protect our enviroment)

5. New unit installed would be more expensive and if $$ is already an issue. The service valve was probably damaged at the original install not being done correctly. The actual valve has heat sensitive parts and alot of installers do not protect them correctly when installing the unit. Make sure the tech that does the work uses either a wet towel or protects the actual valve during the brazing process.