Air Conditioning - Sealing Leaks in AC Lines

My AC Unit is leaking Freon. Since accessing the lines is virtually impossible since they are not expose, a repair technician has recommeded that we try a relatively new product on the market. This product is essentially a sealant that repairs leaks
in the line. It is injected into the line and supposedly binds to the interior of the line and seals the lead.

Have you ever heard of this product? If so, would you
recommend it? Also, are you aware of any drawbacks? I appreciate your response/insights.

Dont do it Run new lines . The compressors dont like it.
It is injected into the line and supposedly binds to the interior of the line and seals the lead.What else will it bind to like the TXV valve

ED;)

It is highly unusual to have a leak in the lines unless there is a joint. If your tech has not injected dye like that manufactured by Spectroline, I suggest he/she does so. This dye is injected, the system topped off with refrigerant, & at some point in the future, the system is inspected with a UV light. Leaks will show up as yellow. I have used this dye & come back as long as two years later & found a leak.
The sealant he/she is talking about does not stick to the surface of the tubing except where where it seeps out & reacts with air to form a seal, according to the manufacturer. I friend in the small appliance business has been using it on high end refrigerators with good success. I personally have never used it so I can't speak from first hand experience.

I don't believe in leak stoppers either. Fix it the real way. Also, the compressor manufacturer will not honor the warranty when leak stoppers are used.

My questions is how did the tech determine the leak is in the line set? Did they isolate it from the rest of the system and pressurize it with nitrogen?

If you are 100% sure then replace the line set as Ed mentioned. If they were just guessing, call another tech.

I'll add my voice to the don't use leak stoppers.
They are a poor excuse for not locating and repairing the leaK.

Leaks in line sets are very rare but I wonder if someone could have driven a nail or screw into the space.
The main areas to leak in my experience are connections at the evaperator and outdoor unit and in the evaperator coil in the furnace. I also have seen several older outdoor units that leak on the end bends in the condenser.

Leaks are sometimes hard to pinpoint but if your tech has a decent leak checker and good techniques he/she will find it/them.

Cant say this is what you have. But a while back we had a unit that had a leak. We went over and over it. Got down to the line set in the wall. After going into the wall we found one place.That with the new power air nailers and small nails in them. The nail went through the wood the drywall the metal guard plate we put on the stud and into the copper freon line.

Have fun
ED:D

This is good to know. Thank you!!
I don't believe in leak stoppers either. Fix it the real way. Also, the compressor manufacturer will not honor the warranty when leak stoppers are used.

My questions is how did the tech determine the leak is in the line set? Did they isolate it from the rest of the system and pressurize it with nitrogen? .

This is the 3rd summer in a row that I've had to recharge the condenser/compressor with freon. Do you think that's a pretty decent sign that there is a leak?

The HVAC sub that installed the unit previously ran pressure checks on the system. He claims that he didn't find a leak allow. Though, I can't imagine he is highly motivated to disclose that there is one.

Final question: Would any of the methods/techniques discussed in this thread for finding leaks reveal one under concrete hardscape? There is a line set run under some concrete hardscape in my backyard. If the leak is there, would I be able to identify it from the methods discusse?

Thanks a bunch!!

If any of this cement is right on any copper lines it will eat a hole in the copper lines.

ED;)

The only method which would really be effective is the 3 section method. Obviously, that won't tell you exactly where the leak is but it will tell you if the leak is in the line set.

The stuff (cliplight super seal HVACR) works in some cases. Certainly not a cureall. I know it has worked three times on small evaporator leaks for me. I would not recommend putting sealer in a new system, all the three that we used them on were older than 10 years and this was a last resort, next step was system replacement, certainly not recommended to just shoot in a system without finding the leak source, plus you must have a perfectly dry system so be darn sure the filter drier is changed and a deep vacuum pulled before the junk is shot in. What type of leak check are they doing? Are they pressurizing with nitrogen and a few ounces of R22? Very rare that the leak cannot be found using good technique although it can be time consuming with split systems.