Originally Posted by litedoc
I fixed it but little wire"fuse" inside didnt stay when it got cold,
Something is causing the fuse to blow... twice! Look for splices in the cable that are no longer sealed. At the end, there will also be a 'termination cap'. Check it as well to be sure it is still sealed.
The fuse is made to blow when too much energy is being drawn. If it worked last year and it doesn't this, something has happened to cause it to blow. Just replacing the fuse or thermostat won't repair the problem.