Solar and cooling?

[TaliaDPerkins]

Nothing yet. I have a room in the back and a hallway. I let the AC run at night and it was able to cool the backend of the bus. It also cooled the front end. The back end next to the AC was of course cooler.

It's not going to keep the bus cool during the day. During the day you will be fighting the sun.

How many degrees below outside ambient would you say you can get the back portion? Have you been in really high humidity environments when it's also hot? How would you say that changes things?

 

[heimlich]

I am in Houston, TX so it is humid here. I just installed it over the winter so I am trying it out now.

 

[TaliaDPerkins]

I'm wondering a little skeptically about full timing in my 13 window Thomas with only 12kw of heat pump. I have most windows deleted, 2.5"~3" of closed cell spray foam on walls and roof, and 3" of foam board below.

The house goes up for sale no later than this time next year -- one way or another this is a plan I am committed to. I have available the slot to place another heat pump or window unit, I may end up doing that.

 

[heimlich]

Some people say a 12k unit will work for a small bus. I'm still trying to figure that out. It works at night which is good enough for me.

You have all Summer to figure it out. Maybe you will need another smaller unit up front.

 

[turf]

its been a few years since i used this and i remember being confused a bit on the r values and their reciprocal work but.... after i got it figured out, i seem to recall my insulated, no window, 30' bus came to 40k btu needed for the temp control i wanted.

Home Heat Loss Calculator

i have multiple heaters so, more than a single source, but the main is diesel (30k btu), electric (idk) and an emergency propane buddy heater. the ac is also 30k.

my temp delta was probably 60 or 80 degrees, from -20 to 60? im guessing, but its been a few years.


edit... i recall also that there is a rule of thumb for rv's. 1000 btu per foot lenght. ymmv
edit #2 - a quick check onthe heat loss calculator still gives me the same result - 42353 btu per hour loss at -20. (heat loss is the same both ways, so i could cool from 140 outside to 60 w/ 40k of ac)

 

[nikitis]

Most RV's don't do 3-4 inches of insulation either, so if you get up to that high R value, your 1000 btu per foot probably increases to 1000 btu per 2 feet.

Which is why we keep telling people to do 4 inches of xps on the floor.