Dehumidifier for the Oliver

[topgun2]

25 minutes ago, davekaro said:

In this situation, are you getting any fresh air into the trailer?

There is always fresh air coming into the Oliver due to the "scupper holes" in the bottom.  Therefore, it all depends on how much fresh air do you want.

One of the first things I always do when setting up my Ollie is to open the bath roof vent.  Then, depending on temps, humidity, precip, etc., I open other windows/Max Air fan (or not).

Bill

[davekaro]

33 minutes ago, topgun2 said:

it all depends on how much fresh air do you want.

Very true. I'd want enough air changes per hour to keep CO2 and VOCs at reasonable levels. Those numbers can be unique per individual, but I would guess the scupper holes on the bottom (from what I saw during the factory tour) are not really bringing in enough fresh air to improve the air quality.

Curious if anyone has setup an air monitoring device that can detect things like CO2. With two people in an Oliver with everything closed, I imagine it spikes pretty quickly. Sorry I'm getting a little off topic. Dehumidifying the air is great, but I'd encourage folks to think about ventilating too. I think the only way that works is opening windows/vents, which makes dehumidifying harder. I wonder if the dehumidifiers can keep up once you open a window/vent. Another option would be to keep everything closed, but every hour (or some interval) open windows/vents to get a load of fresh air to sustain until next time (obviously this won't work while sleeping).

[FloraFauna]

5 hours ago, davekaro said:

Very true. I'd want enough air changes per hour to keep CO2 and VOCs at reasonable levels. Those numbers can be unique per individual, but I would guess the scupper holes on the bottom (from what I saw during the factory tour) are not really bringing in enough fresh air to improve the air quality.

Curious if anyone has setup an air monitoring device that can detect things like CO2. With two people in an Oliver with everything closed, I imagine it spikes pretty quickly. Sorry I'm getting a little off topic. Dehumidifying the air is great, but I'd encourage folks to think about ventilating too. I think the only way that works is opening windows/vents, which makes dehumidifying harder. I wonder if the dehumidifiers can keep up once you open a window/vent. Another option would be to keep everything closed, but every hour (or some interval) open windows/vents to get a load of fresh air to sustain until next time (obviously this won't work while sleeping).

I purchased one of those small dehumidifiers based on this discussion but returned it after one session. It lowered the humidity in the trailer from 78% to 74% after 6 hours - I was not impressed.  I found it is much easier to control the humidity (assuming it is cool enough outside) by ventilation as you describe.  The notion of fresh air and ventilation appealed to me and a small dehumidifier is just noise and nuisance in the system.  I am boondocking almost exclusively, so power consumption is an issue.  I also am generally not camping in wet, humid conditions.  The biggest issue is when it gets cold at night - humidity and condensation will go up if windows are not crack and furnace is not running.  

[Ollie-Haus]

14 hours ago, davekaro said:

In this situation, are you getting any fresh air into the trailer? I would think CO2 and other chemicals would build up quickly. Related, when the AC is running, do you know if it pulls in fresh air or is it recirculating the air inside already? I'm thinking I'd always want a window cracked or roof vent open at least.

We did not have any fresh air coming in for this particular situation as the humidity outside was considerably higher than inside the camper. One unique characteristic of the Oliver design is you are sealed into a “plastic bubble”, if you will. Normally you will want to ventilate to alleviate the tendency to build up moisture in the cabin, but in this situation bringing in outside air would have reduced the comfort level significantly. 
 

My point in the original post was that while we were experiencing cool, rainy, humid weather outside, the comfort level in the Oliver was able to be maintained by only using the portable dehumidifier. Using the Air conditioner would have made the cabin chilled inside in order to try and control humidity, and turning on the ventilation fan only introduced cool air while increasing the already humid conditions inside. It was kind of a third option to use the humidifier only, and turned out to be very effective in keeping the humidity under control. The side benefit was the humidifier puts off a noticeable amount of heat so it actually warmed the inside of the camper while reducing the humidity. Thus not needing the AC or furnace in these particular conditions. You could always crack open a couple windows for ventilation, we just chose not to because it was so comfortable throughout the night.
Again, with experience you will find that the one thing everyone battles in an Oliver is humidity. The AC works marginally at best regarding humidity control, and if the outside humidity is high with lower temperatures, it’s a losing battle. The dehumidifier is a game changer for us and an essential tool in the arsenal of comfort ( think menopause 🙄). 😆

Regarding the AC and fresh air intake, the AC only recirculates cabin air, therefore the ventilation fans and open windows are the only option. I don’t  think CO2 is a problem, although some may be sensitive to slightly increased levels. It would be interesting to bring a CO2 monitor into an Oliver to test levels inside for different scenarios. On the other hand stale air is always the issue with the camper sealed tightly so some ventilation is usually the solution. Hopefully this helps answer your questions. 

Edited June 11 by Ollie-Haus

[Ollie-Haus]

7 hours ago, FloraFauna said:

I purchased one of those small dehumidifiers based on this discussion but returned it after one session. It lowered the humidity in the trailer from 78% to 74% after 6 hours - I was not impressed.  I found it is much easier to control the humidity (assuming it is cool enough outside) by ventilation as you describe.  The notion of fresh air and ventilation appealed to me and a small dehumidifier is just noise and nuisance in the system.  I am boondocking almost exclusively, so power consumption is an issue.  I also am generally not camping in wet, humid conditions.  The biggest issue is when it gets cold at night - humidity and condensation will go up if windows are not crack and furnace is not running.  

That’s interesting your experience with the dehumidifier. Which brand/model did you purchase? There are two primary design principles for electric dehumidifiers, the desiccant principle and the refrigeration principle. Desiccant dehumidifiers only work well at warmer temperatures and loose efficiency quickly as temps drop below 60 degrees, and in general they don’t rate very well in consumer reviews. Refrigeration type dehumidifiers work much more efficiently all the way down to near freezing. Most commercial dehumidifiers work on this design principle. 
 

The model I referenced in my post operates on the refrigeration design and you can literally watch the humidity in the Oliver cabin drop on a hydrometer while it’s running. But the best gauge for humidity and comfort is my wife, and she loves the effectiveness of the little dehumidifier we are using. As a matter of fact, the identical model runs in our bedroom at home every night. 😆

[FloraFauna]

1 hour ago, Ollie-Haus said:

Which brand/model did you purchase?

This unit was a Peltier-type unit.  Not the compressor-refrigeration-type that you suggested, and I knew this when I purchased it.  I have an old Peltier-type refrigerator that has worked well for 20 years and is extremely efficient so I thought I might get some additional power savings with a dehumidifier operating on the same principle. I also liked the smaller footprint.  This unit claimed to dehumidify 850 sq ft - not in my reality.  See: Amazon.com - UBBO Dehumidifiers for Home, 850 sq.ft 95oz Dehumidifier with Drain Hose Timer Sleep Mode Auto-Off 7 Colors Light, Dehumidifier for Bedroom Bathroom Basements RV White

So yes, your point and recommendation are still valid. We find that in cold weather the back windows and back corners of the Ollie can collect condensation.  We continue to experiment with cracking windows and ventilation patterns.  We have also found that rotating the head of the beds from the back corner to the center of trailer combined with judicious window cracking is one approach to avoiding condensation in the back (and it has a side benefit of your head not getting cold in the back corner).  Your dehumidifier recommendation has to be more effective than what we tried but still not sure I want to trade the battery energy if I can manage the humidity other ways.  The fresh air aspect is another consideration. (And I have not lost the link to the unit you recommended - still an option.)

 

[Jason Foster]

I've been shacked up in my trailer working remotely in south Texas for over two weeks now.  I have a much larger floor model that I use to control the humidity, and it works like a charm, bringing the RH from 80+ to a nice crisp 45%.  I am very sensitive to mold, so this is essential for me.  I have also been running the AC constantly because the outside temperature is between 80 and 95 throughout the day.  

I bought the Pro Breeze at Wal-Mart and gave it a 6 hour try.  It removed about an ounce and the humidity rose from 45 to 78 even with the AC on.  Basically useless.  I returned it.  

As far as fresh air?  I don't care about that.  I have a HEPA filter running and I'm not feeling any side effects, so I'm good.  I will likely try the one mentioned by @Ollie-Haus when I get a chance to order it, since the floor unit takes up half the bathroom floor.  Hopefully, it will handle Texas humidity.

[Ronbrink]

4 hours ago, Jason Foster said:

I bought the Pro Breeze at Wal-Mart and gave it a 6 hour try.  It removed about an ounce and the humidity rose from 45 to 78 even with the AC on.  Basically useless.  I returned it.

I suspect your AC is creating the high humidity and the Pro Breeze just couldn’t keep up with it, whereby the larger floor model is  much more efficient and beneficial given your situation and weather conditions. Humidity spikes are inherent to the AC’s continuous fan ON when the compressor cycles OFF and thus, moisture evaporates from the coil fins and the water vapor is returned to the cabin as humidity. 

[DaveK]

On 5/5/2025 at 2:06 PM, Ollie-Haus said:

Regarding when we use this, I leave it on all the time while in storage and plugged in to keep humidity low in the Oliver during storage.

I'm curious how the unit behaves after a power outage when being used during storage.  Does it turn back on without manual intervention?   

The auto restart feature is obviously critical if storing the unit unattended.  

Thanks, Dave.  

[Ollie-Haus]

18 hours ago, DaveK said:

I'm curious how the unit behaves after a power outage when being used during storage.  Does it turn back on without manual intervention?   

The auto restart feature is obviously critical if storing the unit unattended.  

Thanks, Dave.  

Hi Dave, sorry it took so long to respond. I leave our Oliver plugged into shore power when parked at home, and with the lithium system there is never a complete “power outage” that occurs in our situation because it takes over when the grid power blinks or goes out temporarily. 
 

For that reason I couldn’t answer your question without running an actual test of the dehumidifier’s recovery system. Well I did that this morning in the garage by shutting down the circuit I had the appliance plugged into for a minute, and you’ll be pleased to know that the dehumidifier comes back on at the previous setting when power is restored. I hope this helps you and others in deciding whether to invest in one. 👍

Edited 13 hours ago by Ollie-Haus

[Patriot]

@Ollie-Haus

Hey Chris, 

Based on your in-depth positive review and recommendation I just placed an order.👍🏻

No more dehumidifier 🥵 envy! Thanks! 🤣

https://www.amazon.com/dp/B0D7MMW6S5?

Edited 9 hours ago by Patriot

[DaveK]

7 hours ago, Ollie-Haus said:

Hi Dave, sorry it took so long to respond. I leave our Oliver plugged into shore power when parked at home, and with the lithium system there is never a complete “power outage” that occurs in our situation because it takes over when the grid power blinks or goes out temporarily. 
 

For that reason I couldn’t answer your question without running an actual test of the dehumidifier’s recovery system. Well I did that this morning in the garage by shutting down the circuit I had the appliance plugged into for a minute, and you’ll be pleased to know that the dehumidifier comes back on at the previous setting when power is restored. I hope this helps you and others in deciding whether to invest in one. 👍

Since we don't have the inverter on when in storage and connected to shore power I was concerned it wouldn't restart.  Placing my order now.  

Thank you for verifying. 

[Ollie-Haus]

FYI for @DaveK and @Patriot, when you receive the dehumidifier from Amazon, take it out of the box and set it upright on the counter and let it rest unplugged for 24 hours before you turn it on the first time.
 

Like all refrigeration based appliances, if it’s turned on it’s side during shipping, it must be allowed to set in the upright position for 24 hours to make sure the liquified freon and the oils inside drain back to where they normally are during normal operation. This of course applies any time the unit is allowed to lay on its side or upside down. It will certainly be handled like any other package during shipping so don’t forget to perform this procedure to safeguard the internal systems. 👍