Anno 1800 is broken since the last update; Empire of the skies. You build the heaters in the arctic, but the houses are still cold.
You can't turn the conspirators over to Sir Archibald Blake in the A Trifling Matter quest. Please update us on any fixes.
Hey @robcope and welcome to the Ubisoft Discussions!
I understand the houses in Anno 1800 are still at a low temperature despite the presence of heaters. After looking into this, I can see that the dev team is aware of the issue, and it's currently under investigation.
This is also the case for the issue you and @Scott_Harrison are facing with the quest "A Trifling Matter".
Once more information becomes available, it will be posted on the game's forum! 
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