Odd request, temporarily subcool a hallway located adjacent to freezers/coolers

[cchavis]

I have been directed from a room full of geniuses to evaluate 'subcooling' a hallway adjacent to newly installed cooler/freezer equipments.

We are collectively 'stuck' on a renovation project and need to shift equipments around to accommodate 'temporary' usage of cooking/food prep areas. A problem area for this project has been the hallway adjacent to the freezers/coolers with constant condensation issues, partly due to the door being propped open, and the poorly applied visqeen poly sheeting allowing for moist air to enter the space.

next plan of action is to brick up the previously poly sheeted area, add a vestibule/double door set up with an air curtain and to 'subcool' a space to prevent condensation.

I have a compressor rack with a couple of open/ unused circuits, high temp side to 45 deg F that was slated for use elsewhere.

The building we are working on dates to the 50's-60's, located on an Army installation in the Marshall Islands. its constantly hot and humid, WB is 78, with interior hallway temperatures around 80. im sure we could get this down by sealing the building, adding the vestibule.

my plan was to use the existing fan coil unit that was going to go to another room, that wont likely happen for two years in this hallway.

it was sized for a prep room, at 45 deg F, roughly 364 SF; repurposed for hallway at 50-55 (or whenever the sweating stops), roughly 423 SF.

the evap is a russell low volume cooler FL-36-160 putting out 32,000 BTU/hr @ 20 deg temp difference.

i have plenty of reserve on the new refrigeration rack, whereas the future phases are some time away.

My plan was to insulate the walls opposite side of the existing refrigeration coolers. not even sure if this is needed.
i cannot figure if its worth my time and efforts to add an insulated ceiling to the hallway. any path forward is not easy,.

Any input on this hairbrained idea?

site pictures attached.





thx

C

[codgy]

size evap for 15-17 deg. TD to max moisture removal. at that temp coil will still be above freezing, If you run lower than 75 your just moving your condesation issues to outer doors and other walls.

[cchavis]

size evap for 15-17 deg. TD to max moisture removal. at that temp coil will still be above freezing, If you run lower than 75 your just moving your condesation issues to outer doors and other walls.

thanks codgy. think you chimed in on my last situation with the cold storage facility problem. nothing like having to order a few thousand feet of new armaflex to re-insulate.

good segway, re: insulation. i was thinking of adding panels to the opposite side wall to help mitigate condensation to the outer rooms. im also not sure where to stop whereas it will be problematic due to the legacy and myriad of old piping.

is putting up wall panels, changing doors to insulated doors, potential drop ceiling w.insulated tiles worth it??

this is all supposed to be under the guise of temporary, and the target goal is getting rid of the condensation issue. we are not going for leeds platinum, so would like to keep the budget in check.

thx
c

[jpsmith1cm]

Geniuses that don't understand what subcooling is??? Must be engineers.


Prep areas typically have insulation over the drop ceiling. Fiberglass is what I commonly see, but I'm starting to see spray foamed ceilings.

As codgy said, you are, really, just moving the condensation issue.

To resolve it, you have 2 choices:

Raise the temperature of the walls.

Lower the dewpoint of the space.


Obviously, I don't know your budget, but is a portable dehumidifier or two a better option?

Perhaps a smaller dessicant dehumidification system?

That way, you get dehumidification without reducing the temperature significantly.

[cchavis]

Geniuses that don't understand what subcooling is??? Must be engineers.

Even worse, an architect

is it possible to run both in conjunction? i dont have any experience with dessicant systems. this would be a good time to sneak one in on the job so i can get a look see at them. its a constant tropical corrossive environment. we get dry/wet; windy/not windy for weather. all other variables stay the same year around.

[codgy]

I would spec. mechanical dehumidfication in conjunction w/ mini splits to maintain temp. at 72. Provided your box insulation is not ruined this should cover it. One of the sponsors of this site makes a great dehumidifier.

[icemeister]

The condensation on the cooler panels is created because the panel surface temperature is lower than the dewpoint of the air in the corridor.

The solution is to either raise the surface temperature of the panels or lower the dewpoint of the air...or perhaps a little of both.

I have used the desiccant approach some years ago with great success, but it's not cheap.

In this case, I'd first try an very inexpensive experiment with some simple air circulation. Place a few fans or blowers in the hallway to stir up the air. The increased air movement tends to increase the panel's surface temperature, thus reducing the condensation. A more permanent fix would be to install some hardy ceiling hung paddle fans. I've had this work well in a number of situations here in humid Florida. It's worth a shot.

If the fans show improvement but not a complete remedy, then I'd add the evap coil with a 20ºF TD to drop the dewpoint a bit.

[cchavis]

I would spec. mechanical dehumidfication in conjunction w/ mini splits to maintain temp. at 72. Provided your box insulation is not ruined this should cover it. One of the sponsors of this site makes a great dehumidifier.

Codgy,
i cant figure out how to send a private mesage. umm, how do i non-chalantly ask whom the sponsor is?? i've gotten an RFQ in with a vendor, no response as of yet.