Maxxfan Dome installation (previously orientation)

[Townesw]

How does the factory orient the MaxxAir MaxxFan Dome in the bathroom? Installation instructions say orient the fan with the button towards the front of the coach but I’ve seen retrofit installations that orient it differently. 
 

Bill

 

Edited 1 hour ago by Townesw

[jd1923]

2 hours ago, Townesw said:

Installation instructions say orient the fan with the button towards the front of the coach

Yep, that's what I did, per the instructions. It makes sense the button is forward, so that it clasps the fan up front where it takes wind when towing.

Once you get to installation, the curved shape of the Oliver hulls makes it difficult! All exhaust fans are designed to be flush on a flat roof and ceiling. Torque down the screws gently, little-by-little, taking your time so the plastic frame will curve. Too bad Oliver doesn't have a small flat area for this fan in the design of their hull molds.

[Townesw]

34 minutes ago, jd1923 said:

Yep, that's what I did, per the instructions. It makes sense the button is forward, so that it clasps the fan up front where it takes wind when towing.

I took it to mean that you place the power button forward, not the release button. That’s why I posted this question, to get responses from owners whose Olivers had the MaxxAir MaxxFan Dome installed at the factory. 
 

Also, I don’t intend to pull the flange down much to form to the roof curvature. I intend to build the butyl tape up some under the front and rear of the flange where it stands proud of the surface. 
 

Bill

[jd1923]

13 hours ago, Townesw said:

MaxxFan Dome installed at the factory

Do you believe this to be a measure of correctness? I wish OTT always installed accessories correctly in our hull, but their installers made several mistakes.

When I first read "button toward the front" I also thought of the power button. But they show a sketch pointing at the release trigger with the wording, "position toward front of coach." If someone posts a different orientation, regardless of it being "installed at the factory" it would still be wrong.

13 hours ago, Townesw said:

I intend to build the butyl tape up some under the front and rear of the flange

I thought the same thing for about 50 ms when I had the new flat fan sitting on the curved Oliver roof. Then I realized, one good rainstorm while highway towing and the butyl would blow out of the large front gap and you'd have rainwater all in the bathroom. Butyl works best for sealing thin gaps.

You could 3D-print gaskets with a tall front and rear, if you have that capability. I wrote gaskets plural since the fan must be concave on the outside and convex inside.

The plastic frame will curve in place, tightening it little-by-little patiently. I took the day to work ours slowly. A hot sunny day helps to soften the plastic.

Edited May 13 by jd1923

[Steph and Dud B]

Oliver mounted ours wrong, 90 degrees off, and it pops open on the highway. Follow the instructions.

[SeaDawg]

21 hours ago, Townesw said:

I took it to mean that you place the power button forward, not the release button. That’s why I posted this question, to get responses from owners whose Olivers had the MaxxAir MaxxFan Dome installed at the factory. 
 

Also, I don’t intend to pull the flange down much to form to the roof curvature. I intend to build the butyl tape up some under the front and rear of the flange where it stands proud of the surface. 
 

Bill

We did just that about 6 years ago. The butyl has held up just fine for us. Still loving that dome, and especially the light ring.

Where the fan is located in an original Elite may not be as "curved" as the newer II's. I can't tell you, as I've not bern on the roof of a II.

Modern butyl is pretty good stuff.

 

[Townesw]

Thanks for your responses. I found a newer version of the installation instructions online.

My installation instructions dated 09-24-2019 do not have the note on the drawing that the instructions dated 04-13-2021 have regarding what button to place forward.

The old Ventline fan that I removed has a steel base. The butyl tape used to bed it had been built up under the front and rear of the base so as to conform to the roof curvature.

Bill

 

 

 

Edited May 14 by Townesw

[Townesw]

Picture below shows old Ventline fan removed and the roof area cleaned up. I used ASI 0240 adhesive remover and plastic scrapers. I cleaned up the edges of the original holes with a chamfer bit in a drill motor. The factory didn’t align the old vent with the hole very well and didn’t drill and chamfer the holes which resulted in chipped gelcoat. In this picture the pilot holes (1/16”) for MaxxFan Dome are located and drilled. I wanted the screws to be perpendicular to the MaxxFan mounting flange not the roof line so I tried to drill them at the correct angle to the surface of the roof. 

I did a lot of test fitting inside and out. The outside fan, the middle sleeve, and the interior trim ring must fit together well for this retrofit to work out right. I used a carpenter’s pencil and 2 rubber bands from of a bunch of broccoli to hold the sleeve in place while I got the pieces located just right.  I did this before I marked the holes for the flange.
 

 

New pilot holes are enlarged to 1/8 inch and chamfered 

 

Test fit the screws to make sure they are not too tight. If they are too tight you risk twisting the screw in two in the hole. If the test fit is too tight go up to 9/64 inch bit.

 

I used a 1/16 inch drill for a pilot then enlarged with a 1/8 inch drill and finished with a 1/2 inch chamfer bit. Be sure to use sharp bits and drill SLOW.

 

I wanted the flange to be straight, not pulled down to fit the curved roof. I applied one layer of butyl all the way around the bottom of the flange. I then applied 2 short strips between about 10:00-2:00 and 4:00- 8:00. I again applied 2 even shorter strips between 10:30-1:30 and 4:30-7:30. I tried to build the butyl up in the places where the widest gaps would occur, that is the front and back of the fan.  
 

 

 

 

I wiped the mounting location with isopropyl alcohol and let it dry and filled the old and new screw holes with ASI 335 and set the fan in place using a couple of screws inserted through the flange and butyl for alignment. The black button on the handle goes toward the front of the trailer. Work the wires and splice connectors into the space between the hulls while inserting the fan assembly into the hole in the roof. Tighten each screw down a little at a time and try to keep from distorting the flange. I would tighten the screws and leave them for a while to let the butyl push out then I would tighten them a little more until I got the flange sitting like I wanted it to sit and then left the butyl to do what it wanted to for a while. 
 

While the butyl was oozing I went inside the trailer and placed the sleeve back in the hole and made sure the upper edge was against the bottom of the fan and the notch in the sleeve for the wire retainer was in place and using a pencil I marked a line around the sleeve where it exits the curved ceiling. I drew another line 3/8” below this line to account for the interior trim ring and cut the sleeve to this line using a pair of heavy shears and a razor knife and finished to fit with a sanding block. I attached the trim ring and tightened the screws enough to pull the ring up to conform to the curvature of the ceiling.

 

Edited 50 minutes ago by Townesw

[Townesw]

With the inside work complete I went back to the roof area, trimmed the oozed butyl, wiped with isopropyl alcohol again, and taped the area to be caulked off leaving about a quarter inch gap from the edge of the flange in the front and rear and about an 1/8 inch gap on the sides where the caulk would be the shortest. I applied the caulk 3 times, wiping it off the first two times, reapplying the tape and recaulking each time because I didn’t like the way it looked. I finally left it alone because I decided that if I kept messing with it I would keep screwing it up and I was starting to get hungry and it was close to supper time. 

This picture shows the fan after the oozed butyl was trimmed back. It shows the built-up butyl in front of and behind the fan to keep the flange straight.

This next picture is after the ASI 335 was applied. Notice that the black seal is straight, not bowed down at the front and rear due to having the flange pulled down to touch the roof. The black seal must remain straight so that the cover will seal properly when closed.

 

I applied the ASI 335 to the screws but didn’t like the way they looked so I wiped it off. I had applied ASI 335 to the screw holes and the screws were twisted in through between 1 and 3 layers of butyl so I figured they were sealed well enough. 
 

 

The caulk job wasn’t perfect but it looks good from the ground. The ripples are from my hand shaking after going through the process 2 times before finally accepting that it wasn’t going to be perfect. I actually like the stepped edge of the caulk versus a feathered edge because I think the feathered edge of caulk doesn’t hold up well after repeated washing, drying, and waxing. We’ve pulled the trailer through wind and rain for 1350 miles and it has remained closed and hasn’t leaked. It is much quieter than the original Ventline fan.

 

ASI 0240

https://meridianadhesives.com/products/asi-0240/
 

ASI 335

https://meridianadhesives.com/products/?product_search=335

It looks like ASI has two versions of the 335. The stuff I used looked like this

Good luck on your installation.

Bill

 

Edited 13 minutes ago by Townesw

[jd1923]

31 minutes ago, Townesw said:

The caulk job wasn’t perfect but it looks good from the ground.

It actually looks very good in your pictures, so must look perfect from the ground. Job well done and an excellent detailed write-up! 😎

Too bad OTT doesn't make a small flat area for the bathroom fan in their fiberglass molds (inner and outer hulls). It would make for a better fit and make this job easier on all of us!