Plant Decommissioning

[nanuuk]

We are about to under take shutting down a 170,000 sq. ft. refrigerated warehouse for demolition. This is new territory for me and was wondering if anyone has had experience in the past taking on such a task? My main concern is how to go about slowly warming up the rooms so we don't get into to much of a moisture problem if possible and have it start literally raining in the rooms as we are trying to not damage any of the LED lighting hanging in the rooms as well as electrical and also keep it as safe as possible and try to prevent slip hazards. The plant is a 2 stage ammonia plant rotary boosters and recip compressors and in the cold rooms there are floor mounted flooded evaporators average room size is 40,000 sq. ft. running at -18C. Would like to use these evaporators to act sort of like air dryers if you will to pull the moisture out of the room. Any suggestions on how to go about this?

[r.bartlett]

Bring it up in 3-5c stages over a week. hover around 0/+1c for a week the refrigeration will naturally dehum the air
Then take it to +10c for a week and it should be fairly dry by then.

[NH3LVR]

Having, sadly, been through this before there can be a problem with thawing frozen cold storage rooms.
I am assuming that this is an older plant. I had a problem with one with fiberglass insulation. We went to thaw out the room to install an Ice Rake system. The ceiling was full of ice and started sagging when we turned off the refrigeration. We had to turn the cold back on and finish the work in the cold. If you can run the engine room at a higher suction pressure doing what r.bartlett suggested will do well.
I would be very careful.