Craft heating issue with System Heat

[temp_account_9081623478150]

I'm using SystemHeat and Far Future Technologies among many other mods, and when switching to a specific craft only in orbit of Kerbol or loading a save to access it, all parts on the craft are set to 5840K instantly (temperature of Kerbol) despite being just outside of Kerbin's SOI. No parts or FFT engines are generating any heat (checked with debug menu), the radiators are deployed (but do not help), and normally the craft cools down within a few hours in-game. In the save file, "tempExtUnexp = 5840" exists on all parts. I've already tried reinstalling and removing several mods and editing that specific part of the save file. Is there any way to fix this?

The craft this is affecting is a large interplanetary ship with 200+ parts and FFT engines. Another craft in Kerbol orbit that is made of fewer parts which are all near-stock or stock is not affected by this issue for some reason.

This issue seems similar to https://forum.kerbalspaceprogram.com/index.php?/topic/205833-overheating-bug-on-ksp-1122-rss-on-loading-a-save-game/ , however I am not using RSS.