What if I ran my Maxx Air Fan for 7 hrs off my Rv battery? - Fiberglass RV

Thread Tools Search this Thread Display Modes
Old 06-15-2010, 08:32 PM   #1
Senior Member
Trailer: 2009 13 ft Trillium (USA)
Posts: 151
How much would I drain my battery, if I ran my Maxx Air Fan all night, with the battery fully charged. Would it go two nights without driving the trailer around during the day to recharge it? Should I just bring an extra battery? I will be at a campground on the beach of N.C. without hookups and no generator. Whad da ya think?


lloyd cicetti is offline   Reply With Quote
Old 06-15-2010, 08:49 PM   #2
Senior Member
Larry C Hanson's Avatar
Name: Larry H
Trailer: Trillium
Posts: 269
Hi LLoyd
I installed a Maxxair fan and measured the current draw with my ammeter. On low it only drew about 0.3 Amps after it got going. If it were run 7 hours it would only draw about 2AH. Most trailer batteries are at least 80 AH... mine is 130AH. In conclusion, there should be no problem running the fan for a few nights assuming you do not have other, large current draws.
Good Luck.
Larry H

Larry C Hanson is offline   Reply With Quote
Old 06-15-2010, 09:33 PM   #3
Gina D.'s Avatar
Name: Gina D.
Trailer: '77 Leocraft 17 & Former Burro owner and fan!
West Coast USA
Posts: 9,010
I have run my Fantastic fan longer than that with no big dents in my battery.
Gina D. is offline   Reply With Quote
Old 06-16-2010, 12:16 AM   #4
Senior Member
peterh's Avatar
Name: Peter
Trailer: 2005 19 ft Scamp 19 ft 5th Wheel
Posts: 1,519
As Larry has already pointed out, the Fantastic Fan on Low draws pretty minimal power, about 0.3 Amps. Even with that low a power draw, the fan still manages to move a whole lot of air. It also makes a fair bit of noise while it's at it. I find there are times when I want more quiet and less breeze, so I decided to alter my Fantastic Fan to add an ultra-low fan speed switch.

I added a circuit-interrupter switch that re-routes the fan's electric supply through a 10-Ohm, 10-Watt resistor (available at most Radio Shacks that aren't located in a big shopping mall). When switched to its new low-low speed the fan moves a steady, quiet breeze that doesn't dominate conversation over the dinette table, moves just the right amount of air for a warm day or to exhaust cooking fumes so the smoke alarm doesn't go off, and consumes about 0.16 Amps.

Name:   4thFanSpeedSwitch.jpg
Views: 73
Size:  7.3 KB

When the interrupter switch (the black, cylindrical thing with wires leading to and from in the lower right corner of the picture below) is closed, electricity takes the path of least resistance through the normal fan wiring, but, when the switch is open, the electricity has no choice but to go through the 10 Ohm resistor to get to the fan.

Click image for larger version

Name:	4thFanSpeed_6_Small.JPG
Views:	61
Size:	139.1 KB
ID:	28826

The resistor is mounted using a pair of blind rivets (Pop Rivets) that secure its leads to the fan housing on either side of the ventilation opening that allows cool air to move over the resistor coils in the factory speed selector switch. This is quite important because the new resistor will get quite warm, hot to the touch, and needs to use some of the air the fan blows by to cool it.

(Yes, I know the soldering job sucks. My soldering iron wasn't heating properly. It got the job done, barely, and I replaced it after this project.)
peterh is offline   Reply With Quote
Old 06-16-2010, 12:14 PM   #5
Senior Member
Trailer: Bigfoot 21 ft Rear Bed
Posts: 335
Good write-up Peter. The fan in our bathroom (Bigfoot 21R was much too powerful for such a small enclosure. The folks at FanTastic provided us with the same 10W resistor and recommended splicing it into the white wire leading to the motor and placing it in the main airway without the nearby strut obstructing it. They also mentioned that up to two 10W resistors could be used depending on the desired speed.
Steve Dunkel is offline   Reply With Quote
Old 06-16-2010, 12:39 PM   #6
Senior Member
DonDeutsch's Avatar
Trailer: Cloud 13 ft and Compact Jr
Posts: 325
Peter, are you running your fan constantly? Maybe I am looking at this wrong but I don't see how you turn the fan off.
DonDeutsch is offline   Reply With Quote
Old 06-16-2010, 12:57 PM   #7
Trailer: Casita 17 ft Spirit Deluxe
Posts: 51
This from a post that an owner supplied

“Received the resistor and instructions from Fan-Fastic today. Here is exactly what the directions say.

Insert 10W 4 Ohm resister into white-ground going from motor to dome switch. Solder or use two 16 gauge butt connectors.

*Important* -Suspend resistor over fan blade. This insures airflow to cool the resister. Do not mount resistor directly to motor mounting leg.”
Alan #1119 is offline   Reply With Quote
Old 06-17-2010, 01:08 AM   #8
Senior Member
peterh's Avatar
Name: Peter
Trailer: 2005 19 ft Scamp 19 ft 5th Wheel
Posts: 1,519
Peter, are you running your fan constantly? Maybe I am looking at this wrong but I don't see how you turn the fan off.
No, the resistor and bypass switch don't actually interfere with the operation of the fan switches. They are installed midway between the speed selector switch (which has a off position) and the in/out fan direction switch (which also has an off position). With the interrupter switch closed, the fan works just as it did before I modified it. With the switch open, it shunts power through the resistor and the fan runs at its new, super-low speed.

peterh is offline   Reply With Quote


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools Search this Thread
Search this Thread:

Advanced Search
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

Similar Threads
Thread Thread Starter Forum Replies Last Post
best technique for air flow with Maxx Air Fan with 13 footer lloyd cicetti General Chat 4 06-18-2010 05:04 PM
Do I have to use a battery box? Tony Nowak Problem Solving | Owners Helping Owners 5 08-03-2009 09:54 AM
Hooking up boler battery to Tug battery Andy H Problem Solving | Owners Helping Owners 3 08-02-2007 12:59 PM
Takin' it too the Maxx Alf S. Modifications, Alterations and Updates 12 05-07-2007 07:24 PM
Battery In or Out Steve L. General Chat 6 11-16-2005 08:26 PM

» Upcoming Events
No events scheduled in
the next 465 days.
» Virginia Campgrounds

Reviews provided by

Our Communities

Our communities encompass many different hobbies and interests, but each one is built on friendly, intelligent membership.

» More about our Communities

Automotive Communities

Our Automotive communities encompass many different makes and models. From U.S. domestics to European Saloons.

» More about our Automotive Communities

Marine Communities

Our Marine websites focus on Cruising and Sailing Vessels, including forums and the largest cruising Wiki project on the web today.

» More about our Marine Communities

Copyright 2002-2015 Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 02:07 AM.

Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2016, vBulletin Solutions, Inc.