Mini Split While Driving

[cadillackid]

Originally Posted by Ronnie

Oh, no units in the back just air in the dash two small vents near the middle, then one each side round vent just under the dash

thats the LoadStar driver only Option.. was a rare option.. they used a Scout 80 A/C unit in the eary 70s then switched to a Scout II under dash unit in the mid 70s.. the option was discontinued for the S-series busses in 1979..


thats a definite keeper.. or if you dont want it I'll take it off your hands for my restoration on my Superior
-Christopher

[Ronnie]

I will keep you in mind should I decide not to use it.

We have a curtain behind the drivers and front passenger seat, so imagine it would keep the "cab" area cool. However when we have other people with us, is this system likely to keep lets say half the bus cool? Or would I be better to get a system off a modern bus for that?

[cadillackid]

Big thing is stopping engine heat. That’s the big killer.. if your bus has plywood floor that extends into engine compartment make sure the metal from body to chassis is mated correct and that plywood is sealed to metal.. insulatecthe firewall.. close up cracks around wires hoses linkages. Replace grommets and boots .. make your fresh / recite lever and door work correct in your driver heater if it has one.

Most dash air units are 12k btu.. if that one is aftermarket the box might be stamped with the rating or a model number .. the factory loadstar unit was really designed to keep a low ceiling truck cab cool.

Airflow is key.. a unit blowing air out from the dash is going to have a tough time blowing it on people in the seats. Modern bus AC is ducted to the seats or hangs from the ceiling, blowing cold air out over peoples heads which falls into them.. fact is in summer people feel cooler when their faces and arms are cool ..

Of course also depends on how much you are insulating esp the roof and windows, those are huge areas of heat infiltration .. if you aren’t yanking your ceiling and insulating you’ll need a good bit of AC . Tinted windows help a lot..

[TeacherJoe]

Hold on a sec . . .

What about a rooftop unit. I see a low profile Dometic with heat pump for about $1.3k. I can power it off the inverter while driving and a genny or shore power when parked. Simple install, but it adds about 11" height.

Comments?

Joe

[david.dgeorge07]

Originally Posted by TeacherJoe

Hold on a sec . . .

What about a rooftop unit. I see a low profile Dometic with heat pump for about $1.3k. I can power it off the inverter while driving and a genny or shore power when parked. Simple install, but it adds about 11" height.

Comments?

Joe

Those are a lot easier to install, but they tend to be hard on startup for inverters and generators. Also, how many amps is your alternator rated for and at what duty cycle? I’ve generally opted to run my generator while driving if I needed HVAC to keep from toasting my alternator.

My mini splits pull about 100 amps (at 12v) each when running flat out. Most rooftop units will pull double or triple that for a few seconds on startup from my understanding. Easy start capacitors help, but from a power standpoint mini splits are much gentler.

I wouldn’t worry too much about height. Lots of people run those rooftop units, and 18 wheelers are a lot taller than we are. That said, when I was in Chicago there were bridges for the L that I would not have got under with one of those installed.

I have a dometic 13,500 BTU ac unit. Trying to decide to install vs. sell...

[o1marc]

I was thinking an AC unit for $13K was a bit pricey, glad you caught that.

[TeacherJoe]

I saw a $100 unit on eBay that wires up to this unit and makes it do a soft start.

Joe

[TeacherJoe]

Originally Posted by o1marc

I was thinking an AC unit for $13K was a bit pricey, glad you caught that.

Lol. It’s on eBay for around $900.

Joe

[TeacherJoe]

Originally Posted by david.dgeorge07

Those are a lot easier to install, but they tend to be hard on startup for inverters and generators. Also, how many amps is your alternator rated for and at what duty cycle? I’ve generally opted to run my generator while driving if I needed HVAC to keep from toasting my alternator.

My mini splits pull about 100 amps (at 12v) each when running flat out. Most rooftop units will pull double or triple that for a few seconds on startup from my understanding. Easy start capacitors help, but from a power standpoint mini splits are much gentler.

I wouldn’t worry too much about height. Lots of people run those rooftop units, and 18 wheelers are a lot taller than we are. That said, when I was in Chicago there were bridges for the L that I would not have got under with one of those installed.

I have a dometic 13,500 BTU ac unit. Trying to decide to install vs. sell...

I don’t know my alternator capacity. I just got the bus. I’m planning on a 3400/3000 capacity generator.

Joe

[o1marc]

How efficient is a 13500BTU AC unit in 200sf, and 12700BTU of heat? Seems a decent rooftop unit or 2 could save a bunch of interior space, as long as you have the amps to run them.

[TeacherJoe]

Originally Posted by o1marc

How efficient is a 13500BTU AC unit in 200sf, and 12700BTU of heat? Seems a decent rooftop unit or 2 could save a bunch of interior space, as long as you have the amps to run them.

Here are specs for the Dometic unit:
http://www.dyersonline.com/downloadf...tfile_id/3791/
Here’s a generator I’m considering:https://www.championpowerequipment.c...fuel-inverter/

Joe

[david.dgeorge07]

When it says it requires a 3.5k genny, I think they mean running watts, not starting watts. Maybe it will be ok, but remember that rarely is there only one load on your generator.

I have a very similar champion model and I think they are good units but unforgiving of overload. I can run far more on a 20 amp circuit from my house than I can from my 3100/2800 champion.

The one you are looking at is a little bigger than mine, but just remember that you need to allow some overhead beyond a minimum spec, and everything is faster to trip the hotter the weather is.

[cadillackid]

the beauty of minispliots vs camper AC units.. is the fact they are soft start... no start surge.. camper units are glorified window AC's.. not nearly as efficient and are nosiy compared to minisplits..



there are now new rooftop AC's coming out that use the technology and have great efficiency as minisplits.. dometic makes them.. they arent cheap, however they give you many of the mini split benefits without the more -work of installation.. they are easy to drop into the roof.. they are i believe heatpumps also.. so on mild days you can get some heat out of them..



https://www.dometic.com/en-au/au/pro...erter-_-183054


-Christopher

[EastCoastCB]

Originally Posted by cadillackid

the beauty of minispliots vs camper AC units.. is the fact they are soft start... no start surge.. camper units are glorified window AC's.. not nearly as efficient and are nosiy compared to minisplits..



there are now new rooftop AC's coming out that use the technology and have great efficiency as minisplits.. dometic makes them.. they arent cheap, however they give you many of the mini split benefits without the more -work of installation.. they are easy to drop into the roof.. they are i believe heatpumps also.. so on mild days you can get some heat out of them..



https://www.dometic.com/en-au/au/pro...erter-_-183054


-Christopher

We're looking at those. How many roof units u think a 5 window shorty would need?

[cadillackid]

one for using while parked is all youd need.. and those are variable speed so they speed up and slow down.. and this is assuming you will paint your roof bright white and insulate the ceiling at least some.. thats key to any AC working is getting that roof temperature down..



for driving I still stand by installing engine driven Air-conditioning.. if you deem the AmTran dead, pull the dash air and install it in the Freightliner.. you can still sell the AmTran as air-conditioned.. dash A/C was a rare option on AmnTran.



put a Co-pilot seat in for Roxy and you'll both stay nice N cool up front.


-Christopher

[TeacherJoe]

Originally Posted by cadillackid

the beauty of minispliots vs camper AC units.. is the fact they are soft start... no start surge.. camper units are glorified window AC's.. not nearly as efficient and are nosiy compared to minisplits..



there are now new rooftop AC's coming out that use the technology and have great efficiency as minisplits.. dometic makes them.. they arent cheap, however they give you many of the mini split benefits without the more -work of installation.. they are easy to drop into the roof.. they are i believe heatpumps also.. so on mild days you can get some heat out of them..



https://www.dometic.com/en-au/au/pro...erter-_-183054


-Christopher

Interesting. Thanks. If I read the specs right - a big if - it says 230v input. How does change my power requirements?

Joe

[cadillackid]

most of the 3000 watt and above generators have a 230 volt output on them.. im not sure if campgrounds have 230 volt available (if you are planning on staying at a campground alot)..

-Christopher

[EastCoastCB]

Originally Posted by cadillackid

one for using while parked is all youd need.. and those are variable speed so they speed up and slow down.. and this is assuming you will paint your roof bright white and insulate the ceiling at least some.. thats key to any AC working is getting that roof temperature down..



for driving I still stand by installing engine driven Air-conditioning.. if you deem the AmTran dead, pull the dash air and install it in the Freightliner.. you can still sell the AmTran as air-conditioned.. dash A/C was a rare option on AmnTran.



put a Co-pilot seat in for Roxy and you'll both stay nice N cool up front.


-Christopher

Sold the whole IC shorty to Shaun. He's happy as a clam.
Probably not gona worry about road ac. But a roof unit for the many many hours its stationary would be a real nice addition.

[PNW_Steve]

Originally Posted by cadillackid

most of the 3000 watt and above generators have a 230 volt output on them.. im not sure if campgrounds have 230 volt available (if you are planning on staying at a campground alot)..

-Christopher

The 20 Amp service offered at RV parks/campgrounds is 220-240v.


I have been searching for any place in the US that sells the Domestic inverter heat pumps? They are easy to find in Australia

Can anyone point me to a US seller?

Thanks.

[david.dgeorge07]

That unit is 50 hz 240 v for the Australia market. You aren’t going to find 50Hz anywhere here.

See if there is a NA version.

Btw my mini splits were blowing 85F when 18F out this am. Back up to 115F now that it is up to 25F outside.