2021 Tab 400 with 3-way fridge: Bed AC vent at head level...icebox...mod time?

85Redwood

We just stayed for 9 days outside of Little Rock, AR.  The Cool Cat performed admirably in the heat and high humidity.  We have the 3-way fridge so the AC vent in the bed area is at head level.  Any way the vent is rotated there's no escaping the frigid air.  Pointing the airflow directly up is best but deflected air reflects off the curved wall yielding a frigid space and a cold, stiff neck.  The bed area ends up WAY colder than the rest of the camper.  The AC fan speed is set to Low.

The 2 AC vents in the front of the trailer can't be pointed up lest the air gets directed at the thermostat and causes short cycling of the AC compressor.  Ideally, AC vents should be up high but the 400's design can't accommodate that....but I digress...

As a temporary workaround for the bed area air flow DW weaved a thin washcloth in the bed's AC vent in order to block maybe 75% of the air.

Anyone else facing a frigid 400 bed area due to the low AC vent and a super effective Cool Cat?

I'm considering a couple of mods...

Possible Mod 1: relocate bed vent to space left of drawer below fridge

This would involve
1. Cutting the left side of the drawer face below the 3-way fridge
2. Drilling a 4" hole in the panel behind the drawer face that is shared with the bed cubby
3. Relocate the switches for the inverter and bed accent lights to the current bed AC vent location
4. Extend the 4" AC duct through the top of the bed's cubby
5. Relocate the bed's AC vent to the 4" hole drilled in step #2 above

Possible Mod 2: Convert bed vent to 3" and add additional 3" vent following the approach above

Possible Mod 3: Add in-line 4" damper behind drawer that is below fridge

This would allow for tweaking the bed AC air flow after removing the drawer and doesn't require major surgery.

If this worked out a switch controlled powered damper could be installed so that unpowered it would be fully open (daytime) but at night it would be powered to be partially closed.   The switch would replace the current switch for the bed's accent lighting.


Thoughts?  Ideas?

Denny16

The 3-inch vent idea is interesting...

On our TaB400 the dinette seat vents can be rotated to a mostly up position.  I aimed the right side seat to aim slightly above horizontal to miss the thermostat, and the left side is pointed up towards the dinette.  This seems to work well.
cheers

JoeandDiane

We're discovering the same issue, but haven't solved it yet.  @85Redwood, very interested to hear if you have come up with a solution that you like.

RMo

We just slept in cool comfort in Indiana and Illinois by stuffing the vent with tissues, allowing a little air flow.  We had a 5” fan set up for circulation but I’m not sure that’s necessary.  Not elegant, but effective.  I think I’ll try a rotating damper vent when we get back to my tools.

rhyno

Here's my fix.
I tried a Rotaire rotating damper vent from B&B Molders for a few nights and found it still blew way too much cold air directly on us when open even slightly and added an annoying whistling noise. 

I considered the various 4" damper/splitter solutions mentioned elsewhere on the forum but did not want to cut into anything just yet. I replaced the original vent to get back to square one and decided to make a simple deflector.

I took a small plastic container and dremel cut a section from it. The deflector is attached with velcro, there is minimal additional noise and we can adjust to blow the air fully sideways or expose a small portion of the vent if we want some air blowing directly on us. The whole assembly still rotates freely. 
    

rrcbov

I’ve been thinking about either rerouting the rear AC duct to the cubby below the refrigerator or possibly doing a splitter and having the airflow go to both the cubby below the refrigerator and to the existing register.   Either way I plan to add a 12V fan on the wall above the cubby next to the bed.

Katydid

Looks like a great idea rhyno! Would you consider making more of them and selling them? Being limited in my mod capabilities, I’m using a light down pillow to redirect the air! Works okay until I bump it and it falls on my face .

jdjaustin

@rhyno this is genius in its simplicity, and I love that it’s nondestructive!

rhyno

Hi @Katydid - I used an old pet food scoop for my "production" mod and do not have any more of those on hand. If you wanted to try one yourself, I had started with an old 8 oz plastic food storage container that had the same diameter as the vent and cut out a section with a good set of scissors. The velcro is just standard from home depot and cut to fit, with the rough side on the vent and the soft side wrapped around the deflector. I painted mine with spray paint to match before attaching the velcro but that's really just for aesthetics and to satisfy my OCD. If I did not have the thicker plastic scoop already I probably would have just stuck with my prototype and painted it.

Katydid

Thank you @rhyno for the instructions ! It sounds like it may be simple enough to attempt as my first mod. I am motivated as my pillow kept falling on my face last night 😄

[Deleted User]

I'm extremely pleased with the additional vent I added.   https://tab-rv.vanillacommunity.com/discussion/9008/t-b-400-2019-rear-a-c-vent-blowing-directly-in-my-face-solved/p2