Help understanding the wording

Hilly

Under item 2 it says there is no min length of connection for a 5m installation... All I am trying to figure out is if the linesets for this unit have an min length requirement. It is a 12000Btu/h single head unit and if the linesets could be cut down to approx 12-13 feet it would be ideal for location mounting of the unit, slimduct aesthetics, etc. I am a plumbing and it's my own home and I am just mounting the outdoor unit and slimduct, etc. Doing all the prep work for when the qualified hvac tech does the 'hvac stuff' haha. I called my buddy and read what it said and he said it sounds confusing the way it is wrote and he's always followed a min of 15' lineset rule. But he is more commercial based and doesn't deal much with these and has not seen this brand. It is branded 'Windair' but you get Deluxair when you call 1800 #'s and they are a branch of Daikian from the phone trail I am getting. I've tried a few times to get an answer from the company but they never call back.

Any opinions here?

Jamie Hall

Seems clear enough to me -- for the unit with a standard length of connecting pipe (presumably furnished with the unit) there is no minimum length. For the units furnished with longer connecting pipes -- 7.5 or 8 meters -- there is a minimum length -- 3 meters. If you add more connecting pipe, you need to add more refrigerant oil, which stands to reason.

ChrisJ

You also need to keep those linesets immaculate.

Hilly

There is no piping furnished with the unit. Maybe I'm crazy but to say if you install wth 5M standard connections there's no minimum length. Wouldn't that be saying 5m is the minimum length?

ChrisJ

I've never worked with one, but aren't mini-splits just flared connections? If so,my guess is no, you can cut and flare the lineset anywhere you want. Again, keeping the inside of the tubing absolutely spotless. No dust or oil.

Jamie Hall

Hilly said:

There is no piping furnished with the unit. Maybe I'm crazy but to say if you install wth 5M standard connections there's no minimum length. Wouldn't that be saying 5m is the minimum length?

That's not what it says. It seems to me, reading the whole thing, that what is really being said here is something along the lines of...
"if we ship you a unit set up for a 5 meter long connection set, there is enough oil in the unit for up to 5 meters of connection, but not so much as to cause a problem for any shorter length. If we ship you a unit set up for 7.5 or 8 meters, we put 3 meters worth more oil in it, so you are fine for anything between 3 meters and 8 meters. Any less and you have too much oil. Any more, and you have too little."

Or words to that effect. The key is that the amount of oil required in the system varies with the length of the connection, but that there is some latitude in that.

Techman

I think the minimum line set length of 15' is to allow the Expansion Valve a little play room for the normal fluctuations of the EEV, w/o flooding refrigerant back to the comp.

JUGHNE

Is it possible that without a minimum amount of liquid line that the system would be overcharged. I believe on multi-mini splits that you should not operate the system without a minimum number of inside units connected and their line valves opened. It apparently needs to relieve itself of stored liquid before operation?? Needs the room for expansion??

Hilly

I'll just move the mounting and go with the 15'

ChrisJ

Hilly said:

I'll just move the mounting and go with the 15'

Sometimes that ends up just being easier and safer.