I'm about to install a mini-split system in my shop, and several online sources have recommended strongly against coiling extra line set length, because it creates a low spot that traps condensed refrigerant oil.
But in practice I've seen many installations that have low spots in the lines. How bad is this really?
In my case, I have about 5' of line outside, but I'd like to mount the unit as high on the wall as possible. I can't get much higher than where the line set exits the building, and I can run it horizontally from there, but that makes things a little less aesthetic. I'd like to know what my options are.
I don't want to cut the line if I can avoid it, because I don't want to risk flaring the ends (it would be my first time).
Best Answer
one of the diy systems with precharged line sets there instructions specifically state to coil the excess at the system.
Will a low spot be a real problem? I have not seen one although in theory it sounds like it should. Remember the oil is actually carried with the gas/ liquid to an extent so it is being pushed through the system I doubt you will have problems.
The precharged line sets I have seen are 25’ long and when I install a mini split on a single story I usually use less than 12’ so that would leave 13’ to coil up at the compressor.
Get a flaring tool expensive pro ones are under 30$ Cheap ones under 10$. Cut and re flair. Honestly even if I purchase line sets I almost always cut factory flairs off because they are usually sloppy and uneven. On the systems I have pumped down for others the leaks have always been at the factory flairs.
I reflair and wet the surface with nylog (a sealant made for this purpose) torque them down and pump down again with no issues. The extra time costs so don’t be afraid to flair it is quite easy.
As others have mentioned charging a system requires special licenses and training and equipment in most of the world. When the system is pumped down leaks are usually very obvious but the leak location can be harder to find quality flairs are not hard to make just leave an extra foot at the compressor, practice on the pice you cut off then do the real one. (Don’t forget to put the nut on first I have forgotten this when having a beer and BSing with a friend while doing his system, you figure it out real fast lol).