Re: Second ac unit
I installed a 13,5 Carrier low profile AirV. I am not sure what you level of handiness is and that has a lot do do with how easy it is for you.
Like Jim said, getting it on the roof is a trick. I learned a great method on this forum and it worked really good for me. I leaned an extension ladder against the 5th wheel. I then tied a rope to the unopened box and double secured the rope with some Gorilla tape. I then simply pulled the box up the ladder while my wife held the ladder base (yes, she was nervous. She kept saying, "You love me honey, right?).
For me, the hardest (read time consuming) part was removing the old caulking from under the old vent. I used laquer thinner, rags and a puddy knife (very, carefully). It still took a couple of hours to remove the sealant (it is really, really sticky). After that, because it was pre-wired, it was simply a matter of following the instructions.
Our Landmark's roof was thicker than the bolts that came with the unit allowed for. I went to Lowes and substituted 5/16 all thread (threaded rod). The rod threads into tapped holes in the roof unit. I also need 5/16 nuts and washers against the interior mounting plate. Worked very well.
My unit didn't require a thermostat as it was built into the unit. Our Landmark did have a thermostat pre-wire in the ceiling. I have read that the other end is next to the bedroom light switch.
I spent a Saturday on this project and after several trips in 100* plus heat, I am glad I did. Now my wife complains that it's too cold in the bedroom. Also, two a/c's makes you 50 amp dependent.
John