MaxxFan Deluxe 7500K Install Tips/Tricks

manyman297

There are many how-to write ups so I thought I'd give a few tips and tricks that came up during my installation.

This was on my list of upgrades for next year but we couldn't stand how loud and inefficient the Fantastic Fan was. It really is the #1 worst feature on this trailer. Even on low speed it's noisy and uses a lot of energy.

We debated on just doing the Fantastic Fan upgrade where you just upgrade the guts and don't have to replace the entire fan but we store our trailer out in the sun and being able to leave the cover open to vent the trailer during rain was a HUGE plus.

After the upgrade I can confidently say it was definitely worth the $300 price tag. Install started easily but I ran into a couple of snags which I'll highlight here.

Removal

• Surprisingly this was the easiest part of the process. You'll definitely want a plastic razor blade to avoid damaging the roof. Start by running the blade under the sealant enough to where you can grab a good chunk of it. From there if you quickly tug in the direction of removal it should tear off rather easily. If that doesn't go as planned you can score the sealant around the perimeter of the fan so you only are having to remove the sealant on the roof of the trailer leaving the sealant intact on the fan flange. 
• Contrary to popular belief the Fantastic Fan isn't just held on with sealant. The screws holding the trim ring in place on the inside are actually acting as a clamp pull the fan down onto the roof. 
• Removing the butyl tape under the flange can be a little challenging but using a dull putty knife you can break the seal by stabbing it between the roof and flange to the point where you can simply pry the entire fan off the roof.
• Removing the sealant was a matter of using mineral spirits which made quick work of it.

Flange Installation

• Working from through the fan opening was a lifesaver. I'm an average build guy (5'11", 185lbs) and could fit fairly easily.
• Place the flange for the MaxxFan into the opening and from inside make sure you leave enough room for the existing wires. I left just enough to where the new flange wasn't pinching them.
• Use a continuous piece of butyl tape with the start/end seam at the rear of the trailer. The thinking here is that the continuous piece of tape will keep any water from leaking in at the corners and the seam at the back keeps windswept water while driving away from it. I believe the manual even states this.
• I used a hole punch to mark the holes for the flange. You'll need to predrill and I didn't want the bit skating around on the surface of the roof.
• Speaking of predrilling, I used a 3/32" bit and a clamp to keep the entire roof assembly captive. If not, you might drill through the roof and once you hit the aluminum framing, see the entire roof start to rise and cause all sorts of damage. Just keep it all clamped down as you drill. 
• The screws are stainless steel and fairly fragile. I broke a couple and had to make a Home Depot run. Don't use an impact driver. Just use your drill with the clutch set on a moderate setting at first. From there just increase that setting.
• Once you have the flange screwed down wait at least an hour and retighten the screws. The pressure from the initial tightening will cause some butyl tape to ooze out the sides and create some slack between the flange and roof. I was surprised how loose these screws were initially after install. I actually waited a day (because I had to go back to work) to retighten them. 

Dicor Sealant Application

• This is where things went haywire. I must've picked up an old tube of Dicor because a day after applying it there were cracks forming between each bead. I had to remove ALL of the Dicor and start over. Luckily Camping World exchanged the tubes and my second attempt worked out well.
• There are many ways you can apply Dicor. I wanted it to match the factory application of the other vents as closely as possible so I went with the "goop it on" method. I actually think this method is better than simply applying a bead along the edge of the flange/roof and dollops over the screws. Just cover as much as you can and go out about 1.5" from the edge of the flange. I used about 1.25 tubes of Dicor.
• If you want a tidy as possible application you'll probably have to use a battery-powered caulking gun. That way you get a constant output of sealant without having to pump the handle which is what causes some of the wavy, bumpy look.
• My roof is gray so I used gray Dicor and that matched what Nucamp used.
• I've never seen a tidy application of Dicor so don't worry if yours looks terrible. They all do. 

Wiring

• Wiring is straightforward but the biggest hint is to NOT use the spade connectors that come with the fan. They're too bulky and won't tuck neatly back into the ceiling. Use butt connectors (blue) and that will allow you to tuck the wires up into the ceiling gap.
• I would advise to NOT cut the wire lead that comes with MaxxFan. If you ever need to remove the fan to gain access to the roof you'll need that extra wire to allow you to remove the fan and set it aside.

Fan Unit Installation

• The easiest part of the install but can be a little tricky. The main problem a lot of people run into is that the holes in the fan unit don't line up with the holes in the flange. What you can do is pull up on the flange's metal tabs slightly and that should line the holes up. Or you can press down gently on the fan unit and install the screws at an angle and the holes should naturally line up as you tighten.

Interior Trim Ring Installation

• If you have a table saw you can make quick work of trimming the interior trim ring. I trimmed mine to about 1.25" and that worked out perfectly. 
• Predrill the holes with the same 3/32" bit you used on the roof.

Congrats, you're done! I can't believe how much of a difference this fan has made in the amount of airflow and energy efficiency compared to the stock fan. It's worth the hassle.



My first attempt at Dicor. It started to split and crack on the 2nd day of curing.


This is about as good as I could get my 2nd application of Dicor.

Note how the wires are tucked and how you need to use butt connectors instead of the spade connectors that come with the fan.


Finished install.

ColinsTab400

Second round of dicor looks good…. Did you use a spreader or is that how it settles?

Also,  did you do all the outside work from a ladder?

manyman297

@ColinsTab400

Thanks. I found the best thing to do with Dicor is let it do it's thing. No putty knife. Just apply a thick bead and it will settle. I obsessed with how to get it to lay down well but I really don't think there's a great way to get a clean look for this stuff. 

I did the work with a ladder but most of it was done through the hole in the roof (from inside). The only time I really had to put any weight on the roof was when I had to install the screws that hold the fan on the flange. I had some foam insulation board and moving blankets I put down to help distribute the weight from my hand. 

When it comes time to reseal I'll probably have to remove the fan portion and apply Dicor by going through the opening again. Not a huge deal and much easier than trying to reach over the roof to do it.

ColinsTab400

8 foot step ladder enough? 

manyman297

@ColinsTab400

It might be a bit short. Ideally you’ll want something that gets you safely above the trailer looking down…at least high enough that you can lean over the roof to screw in the left side screws.

ColinsTab400

I think drilling the holes is giving me the most stresss.  Are the holes drilled in to aluminum frame that exists around the fan?     Thinking about some staging and a pick so I can get right over it like you advised 

CCC

I am having two Battleborns 100AMP  put in and also the Max improvement here in a month or so. Wonder how much it will cost.

manyman297

Yeah, there’s a fairly wide aluminum frame around the entire fan hole. I just used a hole punch to make indents where the screws go to avoid the drill bit skating around.

As far as staging you won’t need it. Assuming you’re average size you can do 90% of the work through the fan hole in the trailer. Much easier than trying to lean over the trailer doing all of this work. 

ColinsTab400

Thanks for the help.   I installed 2 fans.  Very helpful.  
Notes for anyone following the above thread:
I was able to do most of the work outside on an 8 foot ladder leaning against the padded trailer side.  It was very stable. I used old yoga mats as padding and put very little weight while reaching over.  Some reaches were a stretch... (screws on inside edge of bathroom were the hardest for me.)  
I cleaned and reused the old screws from the bathroom fan and would not use the screws that come with the fan again(two broke and two had to be backed out).  Still use a pilot hole but would use good quality self taping screws.  Pilot hole for inside trim may need to a larger size than above. One roll of butyl tape was long enough for both fans and only used 1 tube of dicor per fan.  (they can't be returned since they are shipped as haz mat so 3 is plenty extra for 2 fans and the vent pipe while you have it handy.
A plastic razor made really fast work of removing old dicor.

Thanks again and good luck for anyone else doing in.   

PS ... have something handy to cover it for an unexpected downpour!

manyman297

@ColinsTab400 Best money spent right? I love ours. 

ColinsTab400

Amazing difference.   Night and day!

tphaggerty

So, I’m finishing the install on mine right now. Is there any concern or history of water getting into the lip around the fan where it drops into the ceiling fitting. I know there’s a gasket there, but if there was a driving rain or if you were driving through rain, it seems like water could get in that seam and eventually drip into the cabin, no?

ColinsTab400

never heard of that... lots of Maxair fans out there

Denny16

I lived for three years in a trailer with roof vents that work the same as the fan vents, and I never had any leaks around the fan hatch, or drips of water into the trailer.  I went through several major bad storms (tropical type driving rain storms)  and an earthquake, survived all of them.
 Cheers 

techietab

Just completed my MaxxFan install yesterday. The tips posted here were helpful - thanks @manyman297!

Some observations from my install that might assist others in the future:

• This might be new thing in the 2022 model year, but unlike others have reported, my fan was secured to the roof with a bunch of Robertson-drive self tapping screws. Have a #1 square/Robertson bit handy before you start.
  
• Unlike others have reported, the factory didn't use butyl tape around the inner edge of the outer frame flange. There was a bead of a very strong, clear adhesive glue around the entire thing that was quite a chore to break. I ended up having to wedge chisels in from the inside to break the seal, and removing the glue was fairly difficult, even with mineral spirits and 3M spray-on adhesive remover.
  
• A plastic razor worked great for removing the old lap sealant, but the real MVP was a heat gun to make everything super pliable.

Additionally - I've read online that Maxxair fans are apparently quite persnickety about voltage input, and are prone to an early death if voltages ever spike too far above 12v. As such, I installed a voltage regulator in front of the fan (spliced in where the fan power cable runs through the back of the microwave compartment.

tphaggerty said:

Is there any concern or history of water getting into the lip around the fan where it drops into the ceiling fitting. I know there’s a gasket there, but if there was a driving rain or if you were driving through rain, it seems like water could get in that seam and eventually drip into the cabin, no?

This concerned me too, so I put lap sealant over that gap. It doesn't seem like it would be too difficult to scrape off/out if needed.

manyman297

@techietab Glad it was useful for you. I too had to deal with that clear sealant the factory used. Not sure what it was but it was hard to remove. 

Humble Road on YouTube had a really good video about the voltage issue. Tempted to install a regulator but will wait until next spring if I do. 

dsfdogs

@manyman297 great video! From folks on the Escape Trailers FB/forum, for which Maxx fans are standard, they too were using the regulators and spraying the boards. They had also heard from Maxx the newer boards can now withstand 14.4 volts. They said be sure to set solar controllers for max 14.4v input. I had the Maxx installed on my 320, with lithium battery and LiS converter, no solar, and never had issues. 

Here is a good video from Adventures in Nomadness showing the board replacement and spraying the coating on it. She also notes the newer boards should be able to withstand higher volts. As a side note, she is using WAGO connectors and those are now standard in Tabs in 2023!

cafyrman

I just sent an email to the Airxcel folks asking about the voltage issues.  I've seen people on other forums say that they were sent a new circuit board that is supposedly more tolerant of higher voltage.  Maybe they're in the fans from the factory now?

Is the white or smoke better at keeping light and heat out?

I've also seen a few posts where people said that the 7500 is better with the thinner roof of the T@B.  The manual just gives a generic 1 1/8" spec for all fans.  I'm debating a 7500 (or 7000) in the main cabin and a 5100 in the bathroom.  No need for the remote in there.

Thoughts?

dsfdogs

@cafyrman I've had the Maxx fan Deluxe 00-06200-K installed on both my trailers. I don't need remote control. I also didn't have the temp sensor installed. I like the look of the smoke hood; certainly heat and light do filter in.

manyman297

I debated about the remote but for me it comes in handy in the middle of the night when it gets too cold or hot and I need to bump the speed up or down.

cafyrman

I'll get the remote for the main fan in the cabin.  Was just thinking about saving some money by putting a less expensive fan in the bathroom.

FuzzyYanni

Here is a video I did on the installation process if anyone else is interested in the upgrade. I think it's a great fan and would also recommend. Excellent job on the OP!
https://youtu.be/45exGtjDAX4