I put an airtight door on my evaporator. Mine is a single door on a rectangular arch front. The door is 3" deep and overlaps the opening on the front of the arch. I put ceramic insulation blanket that that is 4" thick in the door (2-2" bats). When the door closes, it overlaps the opening and compresses the insulation blanket against the front of the arch. The door is larger than the arch opening by 1" on all four sides.
Chad
2014: 12 taps, 5 gal buckets
2015: 15 taps on bags
2016: 150 taps: 100 on bags, 50 on 3/16" natural vac, 2x8 AUF/AOF Homebuilt Arch, 2x8 SL Drop Flu & Auto Draw, SL Propane Canner/Bottler
2017: 225 taps: Built Lean to, Added SL hood, preheater, concentric exhaust, SL SS 7" SB Filter Press
2018: 180 taps: Added Shurflo to 50 - 3/16", Auto fill sensor to head tank
2019: No tapping
2020: 175 taps
2021: 300 taps, homemade RO and releaser
2022: 600+ taps