Which Victron System to Use?

[sunshine_eggo]

It's worth investigating equivalencies. While you might have a 15k BTU unit installed, the improved efficiency of a minisplit may mean a 9k or 12k unit is more than adequate. I got into a pretty intense discussion with someone that did the swap, and they were adamant that replacing a rooftop unit with a minisplit means you can downsize the minisplit.

If you really want to get specific, try calculating the heat load with my handy box heat loss calculator:

Box Heat Loss

Sheet1 Inside, °F,75,°C,10 Outside, °F,120,°C,-6 L, ft,W, ft,R,BTU/h,Comment,L, m,W, m,RSI,W,Comment E,8,8,3.4,847,E,2.45,2.45,0.70,136 W,8,8,3.4,847,W,2.45,2.45,0.70,136 S,39,8,3.4,4129,S,11.93,2.45,0.70,663 N,39,8,3.4,4129,N,11.93,2.45,0.70,663 Roof,39,8,3.4,4129,Roof,11.93,2.45,0.70,663 Floor,39

docs.google.com

Using gross numbers...



A 40' shipping container with R7 on all sides requires 9051 BTU/h to maintain a 75°F interior temperature when the exterior is 120°F.

This does NOT take into consideration any solar heating, i.e., the above is true if the unit is in shade or painted in reflective bright white. I'm not smart enough to figure that out.

 

[chrisski]

It's worth investigating equivalencies. While you might have a 15k BTU unit installed, the improved efficiency of a minisplit may mean a 9k or 12k unit is more than adequate. I got into a pretty intense discussion with someone that did the swap, and they were adamant that replacing a rooftop unit with a minisplit means you can downsize the minisplit.

If you really want to get specific, try calculating the heat load with my handy box heat loss calculator:

Box Heat Loss

Sheet1 Inside, °F,75,°C,10 Outside, °F,120,°C,-6 L, ft,W, ft,R,BTU/h,Comment,L, m,W, m,RSI,W,Comment E,8,8,3.4,847,E,2.45,2.45,0.70,136 W,8,8,3.4,847,W,2.45,2.45,0.70,136 S,39,8,3.4,4129,S,11.93,2.45,0.70,663 N,39,8,3.4,4129,N,11.93,2.45,0.70,663 Roof,39,8,3.4,4129,Roof,11.93,2.45,0.70,663 Floor,39

docs.google.com

Using gross numbers...

View attachment 139455

A 40' shipping container with R7 on all sides requires 9051 BTU/h to maintain a 75°F interior temperature when the exterior is 120°F.

This does NOT take into consideration any solar heating, i.e., the above is true if the unit is in shade or painted in reflective bright white. I'm not smart enough to figure that out.

It seems rating ACs is an art not a science. I do wonder why a 15 k BTU rooftop AC requires a 120 volts, but mini splits top out at 120 volts at 9 k BTU or 12 k BTU.

I would believe a lesser BTU mini split is the same as a HIGHER BTU rooftop RV, but not so much I’ll spend the money and time to cut into the RV to make it.

I have no idea the Rratimg of my RV but I doubt it’s much

 

[Jennifer]