One of the biggest challenges to installing a mini-split is getting the line-set flares together correctly.
The connections need to be sealed well for the system to work properly.
Most DIY mini-split kits will come already with flared ends, but sometimes, these flares will need to be redone.
If the tip becomes scratched or over-tightened, striping the bolt, it will need a new flare.
Flaring the line-set is not difficult with the right tools, with some tips below to help get it right.
What is a Mini Split Line Set?
After bolting the line-set together, it needs to be placed into a vacuum that holds and does not leak.
Once the system is tested for any leaks, the refrigerant is let into the system.
8 Reasons Why A Mini Split Line Set Flare Will Leak Refrigerant
- Flare Is Not Big Enough
- Over Tightening the Flare Connection
- Scratched and Scarring
- Put Oil or Thread Sealer on the Tip
- Incorrect Flare Nut
- The Flare as a Scratch on It
- The Inside of the Tube Should be Round
- Connections Not Tight Enough
If the threads are stripped, they will need to be flared again with new connections.
The best way to stop any over-tightening is to use a torque wrench.
Oil is often added to the tip of the flare tool so there is less friction and a smooth flare surface can be created.
Example Nylog on Amazon
RT201B Nylog Gasket/Thread Sealant
Often, a flare nut that is bad or lost is replaced with a nut that will screw together but is not made for high pressure.
High-pressure fittings have more surface area and are thicker compared to other nuts.
For example, moving it around a concrete slab can mark up the tips sometimes.
Be careful when moving them around, and be sure the flare tool-tip has no scratches.
It should be round with no damage. Often a reaming tool is used to make the tube into the right shape.
Using a torque wrench will give the right amount of tightness needed.
The manual will have the torque amount needed for each system.
Getting a line-set to bolt together properly requires a good flare.
Sometimes it can take a bit of practice to get w nice flare, but it is not too difficult.
Luckily if a flare is bad, only a small amount of the line-set needs to be cut for a new flare.
Using good tools can make a big difference in how a flare comes out.
Also, using a good sealant can make a big difference.
If no sealant is available, refrigerant oil is often used to help everything go together and seal properly.