I had never heard of anyone with that optional fuel heater, sounds neat though if for some reason you didn’t already have blended fuel or wanted to run a higher percentage of bio-diesel in winter.
The most common way to get gelled fuel is to fuel up in Florida and drive north
We already have Blended diesel fuel here in WI (starts in November) and the peak blend is sometime in January. Any fuel you get in northern states or Canada is pre blended at the station so it won't gel up, otherwise you would have diesel cars, trucks and semi's sitting frozen all over the place. Another reason I recommend purchasing fuel from a commonly used stations, is if for example you buy fuel at a low volume station you could be buying 2 month old diesel that isn't blended.
As far as a heater on my fuel filter, I can assure you there isn't one. I just changed it and there is nothing there but the housing and filter.
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