Jump to content


Photo

Condensation


  • Please log in to reply
44 replies to this topic

#21 Jon R

Jon R

    Senior Member

  • Members
  • 906 posts
  • LocationWashington State

Posted 18 December 2021 - 02:56 AM

Here’s where you get Hypervent

https://www.hyperventonline.com/
  • 0

Jon R

2021 Grandby Slide-in Front Dinette

2021 GMC 3500HD CC LB SRW Gas

1993 Chevrolet K2500 Ext Cab LB


#22 Jon R

Jon R

    Senior Member

  • Members
  • 906 posts
  • LocationWashington State

Posted 23 December 2021 - 01:14 AM

I have a question about using Hypervent in the over the cab area: On my camper, the mattress and cushions fit very tight to the walls and slider end board. I can see Hypervent maintaining an air space, but there will be no way for air to flow and carry away moisture because the edges are all closed tight. Does Hypervent still prevent condensation in this type of installation, or does it just hold the mattress above the water until you wipe it up?

Edited by Jon R, 23 December 2021 - 01:15 AM.

  • 0

Jon R

2021 Grandby Slide-in Front Dinette

2021 GMC 3500HD CC LB SRW Gas

1993 Chevrolet K2500 Ext Cab LB


#23 longhorn1

longhorn1

    Ouch, that stings!

  • Members
  • 2,826 posts
  • LocationCarmel, Indiana

Posted 23 December 2021 - 02:00 AM

I have a question about using Hypervent in the over the cab area: On my camper, the mattress and cushions fit very tight to the walls and slider end board. I can see Hypervent maintaining an air space, but there will be no way for air to flow and carry away moisture because the edges are all closed tight. Does Hypervent still prevent condensation in this type of installation, or does it just hold the mattress above the water until you wipe it up?

There were gaps at the corners of the factory mattress in our Grandby and you will get airflow. Cut to fit the HyperVent after pulling out the bed slide so the HyperVent butts up against the 1/2 plywood of the slide. Lift the HyperVent and mattress and push the slide in. Do you have the factory mattress? I was able slide my fingers between the sides and also had a gap along the front. You don't need much as it acts like a Chimney and will pull air
through.

Edited by longhorn1, 23 December 2021 - 02:01 AM.

  • 0

http://texaslonghorns01.blogspot.com/

 

Ford F-250 Long bed, 2014 Grandby

 


#24 Jon R

Jon R

    Senior Member

  • Members
  • 906 posts
  • LocationWashington State

Posted 23 December 2021 - 05:26 AM

I have the factory mattress and the king bed option in my 2021 Grandby. The mattress and cushions fit very tightly on mine with no open gaps anywhere. I could be wrong, but I don’t see how much airflow could occur.
  • 0

Jon R

2021 Grandby Slide-in Front Dinette

2021 GMC 3500HD CC LB SRW Gas

1993 Chevrolet K2500 Ext Cab LB


#25 longhorn1

longhorn1

    Ouch, that stings!

  • Members
  • 2,826 posts
  • LocationCarmel, Indiana

Posted 23 December 2021 - 01:28 PM

I have the factory mattress and the king bed option in my 2021 Grandby. The mattress and cushions fit very tightly on mine with no open gaps anywhere. I could be wrong, but I don’t see how much airflow could occur.

You will have problems without HyperVent if you camp in cold temperatures. You will get airflow. The alternatives are wet bedding and mold. We had gaps in our 2014 Grandby. It doesn't take much. Better safe then sorry. The area for the HyperVent is over the overhang only, not the pull-out portion. I can't believe that you don't have some space. If you can slide your fingers down between the wall and mattress you will be fine. You can take scraps that are left over and install then on the sides if you have a concern.

Edited by longhorn1, 23 December 2021 - 01:34 PM.

  • 0

http://texaslonghorns01.blogspot.com/

 

Ford F-250 Long bed, 2014 Grandby

 


#26 Jon R

Jon R

    Senior Member

  • Members
  • 906 posts
  • LocationWashington State

Posted 23 December 2021 - 07:31 PM

Oh yes, I‘ve experienced the condensation. I also get condensation under the front dinette cushions if someone sleeps there. Thanks for your experienced advice. I plan to follow it. I’m planning to do both hypervent on the overhang and a moisture barrier and mattress pad on top of the mattresses for both beds to significantly reduce the moisture that gets into the mattress in the first place.

Thanks for your advice.
  • 1

Jon R

2021 Grandby Slide-in Front Dinette

2021 GMC 3500HD CC LB SRW Gas

1993 Chevrolet K2500 Ext Cab LB


#27 Vic Harder

Vic Harder

    Doctor Electric

  • Site Team
  • 4,898 posts
  • LocationCalgary, Alberta

Posted 24 December 2021 - 12:02 AM

I find that condensation still forms puddles under the mattress, but the mattress stays dry.
  • 0

#28 ckent323

ckent323

    Senior Member

  • Members
  • 1,216 posts
  • LocationSolvang, CA

Posted 24 December 2021 - 05:30 PM

I have also checked under our mattress and froli spring setup and have found small puddles of condensation yet the mattress remains dry even though it fits snugly all the way around the overcab area. 

 

I like being able to customize the placement of the softer and firmer spring portions of the Froli system but it did take me a couple of attempts to get the best spring configuration for the two of us.

 


  • 0

1993 Dodge Cummins W-250 Club Cab long bed, 2007 FWC Keystone


#29 rando

rando

    Senior Member

  • Members
  • 1,638 posts
  • LocationColorado

Posted 24 December 2021 - 05:39 PM

I have the froli spring setup as well, not so much for condensation management but for comfort.    We regularly camp in cold, albeit dry, conditions and have condensation on the ceiling and behind the arctic pack, but not under the mattress.   I wonder if this is due to the flatbed having storage under the bed which we fill with clothes, effectively insulating the platform the mattress sits on.   

 

Maybe an insulating layer of ensolite foam on the bed platform to keep the surface a little warmer and above the dew point, followed by hypervent or froli springs would work to prevent condensation all together?   

 

On the ceiling anyway we only get condensation where the aluminium framing members are, which are cold.  Where the ceiling is insulated with foam there is no condensation.  


Edited by rando, 24 December 2021 - 05:41 PM.

  • 0

2016 Fleet Flatbed

2016 Toyota Tacoma


#30 rubberlegs

rubberlegs

    curmudgeon

  • Members
  • 560 posts
  • LocationEverett, WA

Posted 24 December 2021 - 05:58 PM

Our FWC mattress bottom is vinyl. I’ve never noticed any moisture, but it seems many others do. Wonder if there is moisture inside the mattress?
  • 0

Tacoma/Fleet 2018.





0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users