Roof top AC on the curve

[T-Bolt]

Today my AC arrives and I would like to get it installed. Quick question is when I reduce the size of my hatch for the AC do I have to have a flat surface to install it on or is it ok to mount it to the curve?

[WIbluebird]

It will conform to the curve. There's a thick rubber gasket at the bottom of the unit that gets compressed by 4 bolts that are screwed into the unit from inside the bus.

[JackE]

This is true, however, the unit does need to sit as close to level as possible for proper function. Just make sure it isn't leaning to one side and it'll be fine.

[EastCoastCB]

Originally Posted by JackE

This is true, however, the unit does need to sit as close to level as possible for proper function. Just make sure it isn't leaning to one side and it'll be fine.

I know in FL they sometimes mount two of them side by side.

[JackE]

Originally Posted by EastCoastCB

I know in FL they sometimes mount two of them side by side.

5 A/C units?? That makes me think my plan for 3 isn't going to be enough!!

I would worry a little about the 2 on the back. I know if you get too much angle on any A/C unit it can allow the oil to go places it shouldn't.

Apparently I shouldn't worry, it must be working for them.

[EastCoastCB]

Originally Posted by JackE

5 A/C units?? That makes me think my plan for 3 isn't going to be enough!!

I would worry a little about the 2 on the back. I know if you get too much angle on any A/C unit it can allow the oil to go places it shouldn't.

Apparently I shouldn't worry, it must be working for them.

Yeah all the Bloodmobiles in my area have 5.

Why I think I need at LEAST one 15k unit for mine.

[BlackJohn]

Originally Posted by EastCoastCB

Yeah all the Bloodmobiles in my area have 5.

Why I think I need at LEAST one 15k unit for mine.

CB, how many amps does a 15K unit draw? You may need a honkin big genny so size accordingly.



John

[EastCoastCB]

Originally Posted by BlackJohn

CB, how many amps does a 15K unit draw? You may need a honkin big genny so size accordingly.



John

somewhere in the 13-16 range.
Planning on at least a 3500-5000w genset. and a 50 amp shore power hookup.

[BlackJohn]

Originally Posted by EastCoastCB

somewhere in the 13-16 range.
Planning on at least a 3500-5000w genset. and a 50 amp shore power hookup.

This surprises me. My old 13.5 has a 20 amp breaker but not sure what it draws exactly. I always run it on low cool anyway. Today is nearly 100F , humid and I sit with no shade, curtains and blinds drawn.
I guess if your figures are correct that genny might do it, 50 amp definitely will.


John

[JackE]

My pop-up camper has a 13.5K unit on it, new last year. My 2K genny will not start it up. I have an old Onan 2250 watt that can start it, but it has to think about it really hard every time it does. My 6.5K Onan I mounted to the bus will run the 2 units from the motor home without any problems, but I'm not sure on the size of those units. I'm planning on 3 roof top units and 50 amp shore. I will be able to run any 2 off the genny, and hopefully all 3 off shore power.

[Booyah45828]

How many amps needed to run an ac unit depends on the unit.

Most people ballpark around 3k surge watts per unit. You definitely don't want to be undersized and tripping breakers all the time. Especially with on a hot day with a sweaty family. Tempers get short quick.

For example, I have a honda eb2500(2.3kw continuous rating) and it won't run the 15k btu ac unit on my bus. But it did run the 15k btu ac unit on a buddy's pop up a few years ago.

The difference is that my unit is likely 20+ years old, and his was a new rental for the weekend. Newer units have a soft starting compressor, and some are even variable speed, which lowers the power draw even more.