I just had a tech over to diagnose my 11 year old 2.5 ton split residential ac system which is blowing warm air. He told me it is totally flat. He spend @ 45 minutes looking for a leak, even using compressed nitrogen, and told me he could not find it. The option he gave me was to fill the system with 5 lbs of R22 with a dye, then wait for it to leak out so the dye would mark the leak. That sounds like a reasonable course of action.
But then he quoted me a price of $519 just to do that, and estimated around $900 total to do the repair if the leak was fixable.
The air conditioning stopped working last October about 2 - 3 weeks after I had new siding put on the house and the coincidence leads me to believe that the siding contractor *may* have either damaged the copper lines coming out of the house or somehow knocked the condenser unit and caused the leak. However, I do realize it could be something else. I just want to know WHAT is leaking before making any further decision. I want the cheapest option and something tells me this guy just wanted to lead me toward a complete new system by overpricing the repair. I am unwilling to accept that I can't get an accurate diagnosis at a reasonable cost before potentially deciding to spend thousands to replace the entire system.
I realize that R22 is getting somewhat expensive. But my gut tells me that $519 to simply fill the system with 5lbs of the stuff (his estimate) along with the dye is excessive, especially since he already charged me $160 for diagnosis and to "clean" the other (working) condenser by running a hose over it for a couple minutes.
What do you think it SHOULD cost just to refill and dye the system to find the leak?