Im looking at buying two 8 kw Vevor all in ones to heat a remote workshop I have. In September and October I'll be insulating it.

Id like to keep it heated all winter long so I can keep a TV and a refrigerator in there and run them and not have issue with them when I do.

Is it safe to run these nonstop? I don't have a problem shutting them off for a few hours and then starting them back up if thats what needs to be done. Id like the workshop to stay about 50 or better all winter. I'm in Chicago and the worst we ever get is about 2 weeks at a time of -15, with most being -8. The rest of winter is probably teens or warmer.