Minecraft Version: 1.12.2
Forge Version: 14.23.1.2586
Mod Version: 1.1
Singleplayer/Multiplayer: Singleplayer

Additional Information:

That's a fault with the boiler scanning code. It only checks to see if it's a functioning multiblock every five seconds. I'm working on better scanning code at the moment, but right now I'm afraid there isn't really anything I can do.

I'm gonna keep this open to keep it on the radar for working on new stuff.