If you even suspect water in the fuel may be frozen. You are probably not dewatering the WVO. This can destroy the injection pump over time.

I do not like paying more than required for fuel. Yet in most cases over time burning diesel will prove to have been cheaper. WVO has proven over time with some exceptions. Save now but pay a lot one way or another later. It was a real craze in north America for some time. As far as I am aware it pretty much has died out now.

A thanks for mentioning that you are using WVO. At one time people would describe their issues. Yet never mention the fact they were using it. For what it is worth. I have had diesels that just refused to start with just one glow plug out. Not perhaps totally logical but it was what it was. They did not have the series glow plugs either.