I don't know if your pumps have seasonal diesel-qualities there but currently the diesel which you get from pump here is rated -26C for storage temp and something like -3xC for using.. Summer diesel would gel. When the weather got cold many cars which had summer-type diesel in tank had problems when the filters clogged etc...
Veggie diesel is even more prone to clog things up in cold enviroinment if no additives are used.
It's been snowing again, official measurement from Kaisaniemi Helsinki weather station is 60cm (23.6 inches about) and counting.
I had a bit of a problem with my breather setup when the temps dropped below -20C and I did a ~150km trip. My breather setup is currently just a hose which goes under the car so it froze. Not badly though, just an ice stick on to the end of the tube but still enough to pop the cam plug seal and spray "some" oil on to the engine compartment.

No damage though but the cam plug seal.. Bit of cleaning and a new plug and the car is running again. I routed the breather hose away from the cold breeze so it shouldn't freeze anymore.
It seems that the current ethanol based washer fluids are commonly rated "only" around -25C. That would be a bit of a problem if temps would go below that as the forecasts show.. Of course the methanol based washer fluids are still legal also and available which are rated for -50C or something but breathing methanol fumes in the cabin isn't quite good for your health on long term.

Finnish made Lasol brand seem to withstand -60C and it's ethanol based but it's also many times more expensive.
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