Reply
 
Thread Tools Display Modes
 
Old 08-16-2015, 02:01 PM   #1
New Member
 
Join Date: Jan 2014
Posts: 6
Year: 1998
Chassis: international bluebird
Engine: T444e 3800
A/C solution with no generator

Hello all,

I have a 1998 international blue bird. I wish to add an a/c unit to keep the bus cool when it is parked. The a/c does not have to run while the bus is moving.

I have two ideas for this:

1.) install one or two rooftop rv a/c unit and wire it so that I can plug it in to a home or business outlet when parked.

2.) install a standard home window a/c unit at the rear of the bus by cutting a hole in the wall above the rear emergency exit door.

My questions are: Will a 50ft or 100ft extension cord be sufficient to do the job of carrying the power supply to the a/c's?

Is it even possible to wire a rooftop unit to work off of a cord connected to a home outlet?

Any opinions or suggestions as to which idea is better or more feasible or economical?

Thank you in advance for any and all feedback. This is a mobile business and therefore I only need the a/c to run while the bus is parked.
crisnpropa is offline   Reply With Quote
Old 08-16-2015, 02:10 PM   #2
Bus Nut
 
onenationundergoat's Avatar
 
Join Date: Mar 2015
Location: Statesville, North Carolina
Posts: 458
Year: 1993
Chassis: Thomas
Engine: International Navistar DT360
Rated Cap: 60
We have a window unit in the back window beside the door. It runs great on a 50ft heavy duty extension cord. Make sure you get a good heavy duty cord, though, so it doesn't melt from the power draw. It's a 10,000btu unit, we're a 32 ft long bus. We have a white roof and reflectix in the windows and it can stay a decent temp (around 74 degrees) in the 100 degree NC summer sun. If we didn't have the reflectix and white roof the AC would not be able to cool the whole bus. You'd need a second one up front.
__________________
My build thread:http://www.skoolie.net/forums/f11/build-thread-for-haulin-oats-and-goats-11237.html#post113500
A gal, a guy, three cats, two dogs, one rabbit, and one goat, traveling the country together.
onenationundergoat is offline   Reply With Quote
Old 08-16-2015, 02:11 PM   #3
Bus Nut
 
onenationundergoat's Avatar
 
Join Date: Mar 2015
Location: Statesville, North Carolina
Posts: 458
Year: 1993
Chassis: Thomas
Engine: International Navistar DT360
Rated Cap: 60
I'd try to stay away from 100ft. The longer the cord the more likely it is you'll melt it.
__________________
My build thread:http://www.skoolie.net/forums/f11/build-thread-for-haulin-oats-and-goats-11237.html#post113500
A gal, a guy, three cats, two dogs, one rabbit, and one goat, traveling the country together.
onenationundergoat is offline   Reply With Quote
Old 08-16-2015, 03:25 PM   #4
New Member
 
Join Date: Jan 2014
Posts: 6
Year: 1998
Chassis: international bluebird
Engine: T444e 3800
Thanks for your information.

I am still curious as to wiring the rooftop units to plug in to an outlet.

My bus roof is white, but when it is parked outside of shade it gets quite hot in there.

How many btu's do you think would be sufficient to keep cool in direct sun?
crisnpropa is offline   Reply With Quote
Old 08-16-2015, 03:58 PM   #5
Bus Nut
 
Join Date: Sep 2014
Posts: 546
Our little 5k btu Fedders through the wall unit draws 3 amps after startup per a Kill a watt meter.

Our OEM bus interior will stay cool enough at 90 IF I run a fan to move the air around.

I run it often in our driveway through a 16g 100ft cord.

We also have an 8k btu portable that draws 5 amps after startup. One at each end cools very well but we usually run the front in the day and the rear near and after bedtime.

If I run both in the driveway for any length of time, I use a shorter 14 or 12g cord.

At a CG our service cord is 12g for our 30amps.
__________________
Don and Mary
dond is offline   Reply With Quote
Old 08-16-2015, 05:46 PM   #6
Bus Crazy
 
somewhereinusa's Avatar
 
Join Date: Nov 2010
Location: Andrews,Indiana
Posts: 1,636
Year: 1991
Coachwork: Bluebird
Chassis: AARE
Engine: 3116 Cat 250hp
Rated Cap: Her, me and Molly
Quote:
Is it even possible to wire a rooftop unit to work off of a cord connected to a home outlet?
That's pretty much how all RV's are wired. There are just circuit breakers and other wiring involved. Even an RV with 50A service can be powered from a 15A cord. I do it quite often, you just have to be very aware of what you try to use. Basically only one big power user at a time. Just to be on the safe side my 100 ft 15A cord is 10 gauge. I have an electric water heater,microwave,laser printer, 120v fridge and 120v induction cook tops, two desk top computers, etc. At the events I photograph I usually only get a 15A circuit. Just only cook one thing at a time. Don't use the AC at an event.
somewhereinusa is offline   Reply With Quote
Old 08-17-2015, 07:09 AM   #7
Site Team
 
Join Date: Jun 2014
Location: southwest lowsyana
Posts: 542
Year: 1988
Coachwork: ward
Chassis: international
Engine: dt360a
Rated Cap: 65
one 5k unit at each end cools in the sun up to 105f. running just one unit cools when temps reach 90f. the windshield is the biggest producer of internal heat. i believe if i would shade the windshield from te sun, one unit would suffice.
claydbal is offline   Reply With Quote
Old 08-17-2015, 10:40 AM   #8
Bus Crazy
 
Join Date: Nov 2011
Location: Sault Ste. Marie, Ontario
Posts: 1,439
Year: 1997
Coachwork: Thomas
Chassis: B3800 Short bus
Engine: T444E
Rated Cap: 36
Quote:
Originally Posted by crisnpropa View Post
My questions are: Will a 50ft or 100ft extension cord be sufficient to do the job of carrying the power supply to the a/c's?
Voltage Drop Calculator
^ Don't guess. Use a voltage drop calculator.

Figure out the running load of the A/C units and all other appliances. Figure out the conductor size of your extension cord. Then use the above calculator to figure out your voltage drop. You want to stay between 0%-5% voltage drop.

Typically 100ft extension cords are 12AWG copper so:

Wire material: Copper
Wire size: 12AWG
Voltage: 120v
Phase: AC single phase
# of conductors: single set
Distance: 100ft
Load current: ?? add up all potential loads
__________________
My build page: Armageddon - The Smell of Airborne Rust
jazty is offline   Reply With Quote
Old 08-17-2015, 12:19 PM   #9
New Member
 
Join Date: Jan 2014
Posts: 6
Year: 1998
Chassis: international bluebird
Engine: T444e 3800
Thanks that is really helpful.

Some additional info: The only appliance I will be running off of the power cord is the a/c unit(s).

Some more background info: I typically drive to the party location, park the bus, shut off the engine. If it is hot outside or I am in direct sunlight then I would need to plug in to a home or business outlet.

I am wondering if one rooftop a/c unit would be sufficient to keep the bus cool in direct sunlight in the summer with 10 children inside.

Thanks.
crisnpropa is offline   Reply With Quote
Old 08-17-2015, 02:43 PM   #10
Bus Crazy
 
Join Date: Feb 2012
Location: Salt Lake City Utah
Posts: 1,328
Year: 2000
Chassis: Blue Bird
Engine: ISC 8.3
Quote:
Originally Posted by crisnpropa View Post
I am wondering if one rooftop a/c unit would be sufficient to keep the bus cool in direct sunlight in the summer with 10 children inside.
Can't find a reference at the moment, but I recall reading that an adult gives off something like 100 watts in heat at rest. If we figure a group of children may produce less heat, but they'd also be more active than an adult at rest, then figure 70 watts per head plus a couple of adults supervising, maybe there are 1000 watts of heat being produced inside the bus. Don't forget they're also breathing and sweating, which adds water vapor to the air and A/C will be have to remove that too before it can cool the air. Plus heat gain from outside (warm air and direct solar radiation).

If the 1 kW figure for internal heating is any good, then about 3400 BTU of the cooling will go to just that. I'm not good enough with psychrometrics to figure how much extra cooling is needed to remove the water from the air.

A problem IMHO with a single A/C unit, even if it has enough capacity to do all the needed cooling, is air circulation. To me it just seems challenging to effectively circulate air through a bus without ducting and good fans. Might be better to eliminate the need for circulation by having multiple cooling units. If a long extension cord is part of the equation, it may also be easier to start multiple small units rather than a single large unit.
family wagon is offline   Reply With Quote
Reply

Tags
a/c

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


» Virginia Campgrounds

Reviews provided by

Powered by vBadvanced CMPS v3.2.3

All times are GMT -5. The time now is 06:39 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2017, vBulletin Solutions, Inc.