MW 22M power to a roof vent

mcfflyer · 09-20-2020, 11:48 AM

I have a 2018 22M that I have a question to those of you who also own one. Have you installed a powered fan in the roof vent over the bed? Putting a new one in the bathroom was easy as it was already powered. Putting a Maxxfan in the cabover was pretty easy too, tapping off of the cabover light. But I’m wonder to those of you have added one in the bedroom, where did you tap off to get power? Can’t use the nearby room light since it’s switched. Got any hints? Thanks!

Morich · 09-20-2020, 01:03 PM

We do not have that trailer but on our motorhome, I wanted to do that on a front vent and used a switched light as a source. My solution is not the super best but worked much easier than other option.
I put a switch on the light so that when we want light, we turn on the wall switch as well as the light switch we leave on. But on the occasions when we want fan but not light we turn the light off with the switch on it and the fan on at the fan. So it winds up the wall switch powers both or we cut off the one we don't want!
In searching for a way to fish the ceiling, I found a metal bar going left/right about six inches out so that I was blocked there. I used a 1/4 inch dowel sharpened to a point to force into the foam before committing to what I would do.

denisd63 · 09-26-2020, 12:31 PM

I just installed a Maxxair over the bed in a 31K, replacing an unpowered vent. Basically you push a hole to the nearest air-conditioning channel, run the wire down that channel until you can push a hole to constant 12v power, in my case the fan in the bathroom.

Use the AC ceiling vents as an access points to poke a hole, so you may have to route the wire on a bit of a diagonal. There are infrequent metal braces that go across the roof that have cut-outs for the AC channel. You may not be able to just go anywhere in the ceiling because you can't get through the braces. A stud detector will find them. Use a coat hanger, pull tape or dowel to punch a hole through the foam and tape the wire to it to pull it back. I used tape on the ceiling to get the angle right. Measure twice and punch through once! Use reasonable wire gauge.

I installed the Maxxair plus shade with a light and connected an in-line dimmer with remote to it while I was at it. I can control all this from the bedside. I am a happy camper.
D

tesscr · 09-29-2020, 09:43 PM

We have a 2020 22M and it’s probably safe to say the ceiling structure is very similar to your 2018.

I replaced the bathroom fan, MB vent, and overhead vent with MaxAir fans. For the bathroom fan, I was able to simply use the existing wiring. For the MB fan, I spliced into the bathroom fan wiring and fished the wire through the ceiling foam over to where the MB vent was. For the cab overhead fan, I tapped into the overhead cab light wiring and fished the wire through the ceiling foam over to the overhead vent opening.

In order to do this, you will need a long flexible drill bit and a fiberglass wire fishing rod. Both items are available at Harbor Freight. I’m guessing you can find similar items on Amazon.

As I recall, the overhead cab was a direct shot without any braces in the way. For the MB fan, I think there was a beam/brace I had to either drill through or avoid in some way.

Regardless, the project only took a couple of hours and went really well. The key is to buy the tools previously mentioned and make sure you you point the drill bit right at the receiving vent.

Good luck.

mcfflyer · 09-29-2020, 11:13 PM

Thanks, tesscr. I did the bathroom and cabover vents as you did. I was looking to see an alternate routing than just going straight from the bathroom vent to the bedroom vent. I'm considering using the a/c ducts to route the wire part of the way, and only drilling into the nearby ducts from each vent. Probably a project for next year. Thanks!

kcscriv · 10-04-2020, 07:15 PM

Hi Dave here, I also have the 22m 2018, when doing the bathroom fan replacement is it all done from in the bathroom or do you have to also modify things on roof? I-mate to mess with the seals on roof, I realize I will have to change my vent cover up top but that does not disturb roof seals, thanks for help, did you get fan from camping world if so what is the replacement number for power fan.

mcfflyer · 10-04-2020, 10:14 PM

Dave, I’m not sure what you mean regarding the roof seals. I am unaware how you could replace the inside portion without replacing the whole unit I don’t know how you could put in a new roof vent without removing all of the old sealant. Removing the vent required me to use a plastic putty knife to break the seal around the original vent and then scrape off all of the old sealant so I’d have a clean roof surface to put the new new vent in and reseal everything. I put a Maxxfan 4500K in the cabover and a Maxxfan 4000K in the bathroom, both from Camping World. Am very happy with them both.