He has a line set of 1/2" and 1/4", but the manufacturer calls for 5/8" and 1/4".

he bought the thing on line, there isn't a warranty anyway.

CoolAir list the fine print of the warranty for ANY AC unit bought on line. There is no warranty for a DIY machine.

He didn't have to mention that he bought it on line... the question he is asking is a noob type question. 75% of this job, is knowing what not to do.

This 75% knowledge isn't attained by reading manuals etc.

So a 'professional' needs to buy an AC unit online? Nope.

An unlicensed person? yes. because a physical local store will not sell it to unlicensed people.

So you think: that if you buy a unit online have someone install it, then when it breaks you can call who ever you want to fix it right? uh no.

The picture above is from a service call I ran on a unit just under a year old, installed by a 'so called professional'. The initial call the home owner was under the impression that the call 'should be covered under warranty' --- nope, not by a HVAC contractor who didn't put it in first of all.

Because of this situation, my recommendation was to take this furnace out and replace it with a new furnace installed properly.

The home owner didn't like that. But this was his choice thinking he would save so much money buying a unit on line. Do I know it was bought on line? No, I can only assume it was. My business is firstly predicated on controlling risk. I am not going to assume risk in something someone else did. (some other company, person, hack whatever you wish to call it.)

NOTE: THIS UNIT IN THIS PICTURE ABOVE WAS NOT, I REPEAT WAS NOT INSTALLED BY AUSTIN AIR CO.

So this homeowner, was left to chase down the 'so called professional' who installed it.

How do you know it was installed properly or not? If your vision of a professional install is to put towels under the unit to soak up condensation, you need your head examined.

Again: There is NO WARRANTY on a unit bought on line.

A 'TRUE' professional has no need to purchase anything on line.

I service the Katy, Texas area.

Mitsubishi warrants its DIY line - "Mr Cool". Of course, only manufacturing defects are covered (as with any manufacturers warranty).