Upgrade Bathroom Fan

[Ronyx]

I am contemplating an upgrade to the stock Ventline extractor fan in the bathroom of our 2017 FC19. According to the Ventline’s specifications, it has a volume of 100cfm.

I would like something with more volume. I found a Maxxair version that claims to draw double the volume at 200cfm. I also notice that the Ventline claims to be 6-1/4” diameter, whereas the Maxxair is 6”.

Has anyone attempted this replacement or have other suggestions?

Thanks for your help

[twbucksr]

Upsizing your exhaust fan may not fix your problem.

First let’s do some math. Let’s assume that if your 19’ FC was just a shell it would have less than 800 cubic feet of volume.

That means that every 8 minutes the factory installed 100 cubic feet per minute (cfm) exhaust fan runs, it has replaced 100% of the air inside your Airstream provided there is enough unrestricted, FREE AREA of openings in your Airstream (open windows, vents, etc.) for the 100 cfm of air to get into your Airstream be exhausted out.

In other words, if you are not providing your exhaust fan at least 30 square inches of free area openings when it is on it is not exhausting 100 cfm of air.

Doubling the cfm of exhaust would require doubling the amount of free area for air to get in for the exhaust fan to be effective.

[Ronyx]

Originally Posted by twbucksr

Upsizing your exhaust fan may not fix your problem.

First let’s do some math. Let’s assume that if your 19’ FC was just a shell it would have less than 800 cubic feet of volume.

That means that every 8 minutes the factory installed 100 cubic feet per minute (cfm) exhaust fan runs, it has replaced 100% of the air inside your Airstream provided there is enough unrestricted, FREE AREA of openings in your Airstream (open windows, vents, etc.) for the 100 cfm of air to get into your Airstream be exhausted out.

In other words, if you are not providing your exhaust fan at least 30 square inches of free area openings when it is on it is not exhausting 100 cfm of air.

Doubling the cfm of exhaust would require doubling the amount of free area for air to get in for the exhaust fan to be effective.

So you don't have experience with the question asked? Also, to answer your question, volume of replacement air is provided by a window, door or fantastic fan being open so no issue there.

[lsbrodsky]

Wow, a rather snarky response to someone just trying to suggest you may not need to do this. I don't have the experience changing the fan, just the opposite. I was one of the guys who decided I needed less volume and installed a motor controller to make my fan speed adjustable. Although my layout is different than yours, I have found in 7 years of showering and shaving in temps ranging from 35-100 F, that the installed fan speed is more than adequate for exhausting all of the moisture in short order. I never need less exhaust for the shower, but always need less volume for the sink/toilet area.
Larry

[Ronyx]

Originally Posted by lsbrodsky

Wow, a rather snarky response to someone just trying to suggest you may not need to do this. I don't have the experience changing the fan, just the opposite. I was one of the guys who decided I needed less volume and installed a motor controller to make my fan speed adjustable. Although my layout is different than yours, I have found in 7 years of showering and shaving in temps ranging from 35-100 F, that the installed fan speed is more than adequate for exhausting all of the moisture in short order. I never need less exhaust for the shower, but always need less volume for the sink/toilet area.
Larry

Not meaning to be snarky but the point is that I asked for experience replacing the fan, not for validation/evaluation of my reasoning or purpose for doing so.

[A W Warn]

I have no personal experience with the Maxxair dome fan. But, I read a review just this week, somewhere.... that I could not find just now when I looked.
What I remember about that review:
It is quieter
One version (Dome Plus) had a built in switched LED light, which the review said was a good night light
It fit the existing hole where a Ventline Vanair fan was removed.

ps:
Another thing I remembered:
The fan is designed for a 1" thick ceiling structure. There is an accessory collar/extension kit that has to be purchased when installing it in ceilings thicker than 1" and up to 6".

The only thing I did not like was that it was not mentioned if it is or not available with a translucent lid that would let in daylight.

[Ronyx]

Originally Posted by A W Warn

I have no personal experience with the Maxxair dome fan. But, I read a review just this week, somewhere.... that I could not find just now when I looked.
What I remember about that review:
It is quieter
One version (Dome Plus) had a built in switched LED light, which the review said was a good night light
It fit the existing hole where a Ventline Vanair fan was removed.

ps:
Another thing I remembered:
The fan is designed for a 1" thick ceiling structure. There is an accessory collar/extension kit that has to be purchased when installing it in ceilings thicker than 1" and up to 6".

The only thing I did not like was that it was not mentioned if it is or not available with a translucent lid that would let in daylight.

Thanks for relaying the review. It’s nice to hear that the Maxxair is quieter and fits the Ventair location. On e-trailer I noticed the lighted version you mentioned. Also, the version on e-trailer appears to include the spacer collar.

[dhroberts]

Originally Posted by lsbrodsky

Wow, a rather snarky response to someone just trying to suggest you may not need to do this. I don't have the experience changing the fan, just the opposite. I was one of the guys who decided I needed less volume and installed a motor controller to make my fan speed adjustable. Although my layout is different than yours, I have found in 7 years of showering and shaving in temps ranging from 35-100 F, that the installed fan speed is more than adequate for exhausting all of the moisture in short order. I never need less exhaust for the shower, but always need less volume for the sink/toilet area.
Larry

Kudos for your snarky caution. For this site to be effective for beginners through experts, there are no poor questions. Further, if a response is more expansive that what was originally requested, there are often important considerations that can be of unexpected interest. Thanks again.

[smithcreek]

Originally Posted by Ronyx

Not meaning to be snarky...

And yet you were. Maybe it's just a natural talent!

[Ronyx]

Originally Posted by smithcreek

And yet you were. Maybe it's just a natural talent!

perhaps, thank you for pointing that out

[Airstreamfan]

I'll just say this, having moderated a woodworking forum for 10 years. Woodworkers are some of the most passionate arguers on the planet, and many also have very thin skin.

You're a heckuva lot more likely to get a lot of good answers to your questions when you don't berate someone trying to help you. If you don't like what you're reading, move on to the next, or just say a polite "thank you."

I know I'm not about to waste my time typing up a solid answer to a question if the person asking the question doesn't come across as being very nice or receptive.

Just a thought for next time......

Airstreams are made of thin aluminum. Aluminum is one of the easiest metals on the planet to cut, if needed. If you choose a fan with a bigger hole diameter than what is already there, you can easily make an opening bigger. If it's smaller by a little bit, in this case a 1/4", that amount is always easy to cover up with the flashing used during the install. In extreme cases, patch panels can be made and riveted in to close up existing holes that are no longer needed, of course, in every instance, utilizing the proper sealers for the job to prevent water penetration.

[Ronyx]

Thank you for your feedback

[DoublTrouble]

Did you install it?

I am thinking about the same project.

[jcanavera]

As another person had noted, increasing the exhaust capacity in the bathroom does mean you need to be able to makeup that air being exhausted from that fan. This becomes apparent when you are in the throws of summer camping with the air conditioner running, or when you need heat on cooler days and nights. As the existing bathroom fan runs, I typically find that that the make up air is coming from all kinds of locations in the trailer. In my experience with my 2004 Classic and my 2001 Safari, the heating and cooling systems are triggered within a minute or two of the activation of the bathroom fan. And typically these systems will run longer when the bathroom fan is running and either over heat or over cool the trailer, dependent upon what system the thermostat is set for. The thermostat wiring for heat and cooling units pass through the wall where the thermostat is mounted and inevitably air leaking through those holes will trigger the thermostat to call for heat or cooling dependent upon the season of the year and outdoor temperatures. Typically Airstream chooses a wall to mount the thermostat which is very close to, or may be part of the refrigerator enclosure. Thats an easy draw for make up air for the fan although that's not the reason the wiring is routed that way. It doesn't take much airflow to fool the sensor into calling for heat or cooling (even though inside temperatures are right on target) once that bathroom fan is activated. Caulking those holes will help greatly correct this situation.

Jack

[DoublTrouble]

That's important to know. Actually, my expectations are not for the the increase in cfm, but more about sound and appearance. I have completed this mod below, which is great for reducing sound running at 50% for light ventilation but as with the Fantastic Fans, I believe that the MAXXAIR product is superior.
My current work around at night is to leave Ventlines open and MaxxAir fan on "in" with the same effect. While showering, the Ventline on high is tolerable and effective enough.

https://www.airforums.com/forums/sho...d.php?t=191363

Anyway, still thinking about this...

Thanks.

Jeffrey

[WineStream]

Can anyone comment on the need for the extension/spacer? I see the "only for 1" roofs" with LED model for sale for about half the price at camping world vs. the same model but with 6" extension at etrailer. I have limited experience seeing a cross-section of my Airstream roof, but I thought it was more like 2". Can anyone comment on roof thickness and/or the need for the extension model of Maxxair fan replacement for the ventline?

[WineStream]

Originally Posted by WineStream

Can anyone comment on the need for the extension/spacer? I see the "only for 1" roofs" with LED model for sale for about half the price at camping world vs. the same model but with 6" extension at etrailer. I have limited experience seeing a cross-section of my Airstream roof, but I thought it was more like 2". Can anyone comment on roof thickness and/or the need for the extension model of Maxxair fan replacement for the ventline?

So I went ahead and bought the MaxxAir with the 6" spacer. Good thing I did.

The hole in my roof was perfect, so no mods there. The roof of my Airstream (2005) is 2" thick. I ended up cutting the spacer to 2-3/4" as it protrudes a bit down in the interior bezel that MaxxAir provides.

Seems like the airflow is about the same as the stock fan, but the new one is quieter. Will see if it stays that way. I bought the model with the LED light ring...it's bright! I was thinking it would be a boondocking night light to leave on al night but it's so bright that it would shine out below and above the bathroom door and bother me if I woke up in the night.

[DoublTrouble]

Thanks WineStream. Keep us posted. I'd still like to do this mod but spending bundle on frame separation right now...[emoji18]