A/C Leak Freeze with Magic Frost Review

LDSC00069ike many, our home is cooled by an aging heat pump originally built in 1993. It’s been a good unit, but last summer the fan on the heat pump gave up the ghost and had to be replaced. Soon after, we noticed it was not cooling as it should and was blowing nearly 70 degree air inside the house with the thermostat set to 82 degrees fahrenheit. Generally, you want to see a 20 degree “split” – that is, the air exiting the air handler should be 20 degrees cooler than the incoming air. In our case, the incoming air was between 76 and 77 degrees with the basement air in the mix, giving a 7 degree split. Not good. Furthermore, we noticed the interior A-coil, called the evaporator, freezing at the bottom which is an indication the system is low on refrigerant.

The HVAC tech only confirmed what we already knew, that we had a refrigerant leak. He said it was a pretty substantial leak on the order of a pound of R-22 refrigerant a month. Service calls are not cheap and neither is the refrigerant, not to mention that refrigerant leaks are not exactly eco friendly! On old units, like ours, repair is seldom an option. The labor costs involved with finding a leak are substantial and, as explained by the tech, even if the leak is found, it often is not repairable. Our suspicion is that the condenser coil, located on the heat pump itself, started leaking after the fan replacement. The fan replacement process involves partially disassembling the heat pump and leaves the condenser coil unsupported and vulnerable to damage. With repair an expensive prospect, there were two options left – total replacement or a stop leak product. Since this nearly 20 year old heat pump would be headed to the scrap heap anyway, we decided to try “A/C Leak Freeze with Magic Frost.

According to the manufacturer, A/C Leak Freeze is “not activated by moisture or oxygen” meaning that it shouldn’t “gum up” the controls inside the air conditioning system like many other products. Our HVAC tech assured us the worst that would happen with A/C Leak Freeze is that it wouldn’t work at all. Before giving the OK, I did some homework online and read reviews on HVAC forums; many techs advised against putting stop leak type products into an air conditioning system, but the ones that had used A/C Leak Freeze had not experienced any compressor failures. Furthermore, many noted that A/C Leak Freeze had successfully stopped small refrigerant leaks on systems deemed “over-the-hill!” This was certainly encouraging and we forged on.

Actually using A/C Leak Freeze is simple; the heat pump or air conditioner must be running, then the syringe is connected to the low side service port on the suction line.  At this point, A/C Leak Freeze is slowly injected into the refrigerant. Due to high pressures, pushing the syringe in by hand can be difficult so the manufacturer recommends placing the syringe in a caulking gun. Once A/C Leak Freeze is in the system, the refrigerant should be topped off and then the heat pump or air conditioner should run continuously for at least 30 minutes to circulate the product. That’s it!

So far our system has been kicking out 58 degree air ever since the refrigerant has been topped off and A/C Leak Freeze with Magic Frost added, with no refrigerant loss noted. We’re hoping this is one for the “success” column! Please note, carefully weigh the pros and cons before adding A/C Leak Freeze to your HVAC system. While it seems to have worked successfully in our case, I still feel it could be damaging and it should only be used as a last resort on systems not worth repairing!

*July 30th Update*

The A/C again measured down to 58 degrees a month later. The compressor is still going strong so it seems like A/C Leak Freeze did the trick!

*August 30th Update*

The A/C continues to work. The last measured temperature was 62 degrees, but given the different environmental conditions I’m not sure how much meaning can be derived. Perhaps some ground has been lost or maybe it’s perfectly fine. Either way, the compressor is still running just fine and the A/C is blowing cold. I think it is clear that the A/C Leak Freeze product helped slow or stop the refrigerant leak.

*June 20th 2014 Update*

It’s still going! See the video here. 

  • Jon

    Hi, thanks for publishing the leak freeze review.

    I’m surprised you had such ease installing the leak freeze fluid. Like you, first I tried “plunging” by hand, no luck. Then put in caulk gun, bad fit! The leak freeze tube is much narrower than a tube of caulk. Tube kept getting misaligned and the flimsy plunger buckled.

    Luckily I found a large washer to adapt the leak freeze tube to the end of the caulk gun, and then found a large metal drill bit that could take the pressure of the caulk gun compression.

    I got the “magic frost” (lubricant) version, and the compressor is starting easier and running quieter.

    I wish they would just design the product to fit in a caulk gun.

    In any event, time will tell if it helps with leaks.

    • RJ

      I’m glad to hear it seems to be working for you too. Our heat pump is still going strong – I’m sure it’s not a permanent fix, but it beats the heck out of replacing it during the peak of summer! And it certainly would make more sense for them to design the product to fit in a caulking gun.

      • Chris

        Do you have an update for this?

        • RJ

          The heat pump is still going strong. I’ll post an official update soon!

          • Chris

            Just had Leak Freeze added to my system this morning. Fingers crossed.

          • RJ

            @Chris, any updates?

  • sparkle

    I need help coming up with a way to inject this stuff in the suction line. Even with a caulk gun I cannot get it to go in. Thanks!

    • RJ

      I’ll look into it. Our A/C tech was able to inject it by hand (not recommended!) with the system running – if it doesn’t go in with the aid of a caulk gun, it seems like something is wrong?

  • Jim

    Jon and RJ any updates on how your systems are doing?

    • RJ

      @Jim, my system finally bit the dust about two weeks ago. The refrigerant finally leaked enough that it was no longer effectively cooling, so we had a new Trane system installed. The Leak Freeze certainly helped slow the leak, but it wasn’t a permanent fix (not that I expected it to be).

      • melinda

        did you find that the leak freeze clogged the piping under the house? When it was to time to purchase a new unit was there build up of any kind in the pipes

        • RJ

          Unfortunately, I did not see the inside of the lines when the unit was replaced. My guess is that yes, there likely was a light build up inside.

  • Kevin Kuras

    Ok just had 4lbs filled in my ac ….. $312 and then he tells me that the evaporator coil is leaking. Uggggggg so of course I got online to price them out….. Again ugggggg. My outside unit is 1995 and my inside attic unit is way newer…… I am willing to try the Leak Freeze. When is a good time to add it? Do I wait till it gets low again then add it? Do I try to force it in while its full?

    • Cyrix2k

      I would add the A/C Leak Freeze when the unit is still full. If you wait until it is low, you will need to pay to have the system charged yet again. Do remember that your mileage may vary and this is a temporary solution at best – I also think it’s worth a shot, but you’re definitely on borrowed time.