TT Solo 110 won't fire up, seems to be Low Pressure code

I'd appreciate any thoughts on starting my Solo 110 this year. Last year it had a low pressure issue. I ran it up to 20 psi and it was a good winter. This year I have a code error b26 that seems to be for low pressure. I've run it up to 26 psi and still no go. I don't think I 'd want more psi than this.
Any thoughts?
Any experience with techs/services in the Twin Cities. My guys are no longer in bussiness.

Thanks, Bruce

Paging Morgan Audetat...

http://www.badgerboilerservice.com/