How much should a 5lb refill with R22 + dye *

[DFDalton]

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 *

[heatseeker]

You said he used nitrogen and leak checked system, *
Cost of electronic leak * 400.00 bucks
cost of nitrogen and regulator approximately 200 bucks
cost of gas to get to your house 20 bucks conservatively.
cost of r-22 50 bucks a pound * 250 bucks
time 100.00 bucks.
total 970.00 dollars I would say you are getting off cheap.
Understood that tools can be used over and over again but they do not last forever and need to be replaced occasionally.
If your leak is in the lineset you got more problems and it will cost. My advice if your system is over 12 or 15 yrs old replace with r410a system. Oh and I am not pushing any equipment either, it is in your best interest to get rid of antiquated equipment.

[Freon]

Your idea about the siding contractor makes sense. Where the copper lines exit the house and all around the condenser unit look for a small oil stain. As R-22 leaks so does the lubricating oil. Also check any place where there is a connection. If no oil stain, run your hand under the connection to double check for an oily feel.

If the leak is in the wall due to a errant nail, you have a pita problem. Do you know how the copper tubing runs from the condenser to the evaporator * Since the system is totally empty you could pressurize it with CO2 at the service valve on the condenser unit and then close the service valves. If the pressure holds then the leak is in the condenser unit. If the pressure drops then it's in the copper tubing or the evaporator coil.

You may need to cap the copper tubing at the evaporator coil and make sure the leak isn't in the copper tubing within the walls of the house. If it is, time to cut a hole in the wall. This is all work that you can do but you will a pressure gauge and a way to connect it to the service valve. There are inexpensive hoses at HVAC stores or maybe eBay that will attach to the service valve and gauge. Good luck.

[heatseeker]

Freon -
> Your idea about the siding contractor makes sense. Where the copper lines
> exit the house and all around the condenser unit look for a small oil
> stain. As R-22 leaks so does the lubricating oil. Also check any place
> where there is a connection. If no oil stain, run your hand under the
> connection to double check for an oily feel.
>
> If the leak is in the wall due to a errant nail, you have a pita problem.
> Do you know how the copper tubing runs from the condenser to the evaporator
> * Since the system is totally empty you could pressurize it with CO2 at
> the service valve on the condenser unit and then close the service valves.
> If the pressure holds then the leak is in the condenser unit. If the
> pressure drops then it's in the copper tubing or the evaporator coil.
>
> You may need to cap the copper tubing at the evaporator coil and make sure
> the leak isn't in the copper tubing within the walls of the house. If it
> is, time to cut a hole in the wall. This is all work that you can do but
> you will a pressure gauge and a way to connect it to the service valve.
> There are inexpensive hoses at HVAC stores or maybe eBay that will attach
> to the service valve and gauge. Good luck.
Yea I can see him running out and buying some co2 and a regulator just to find a nail in the line.
You are right though if their is a hole in the line pita to find where.