thought i had ballast problems,but it is not firing from elec. from house.can plug any other device in to outlet and they will work,but ballast only fires sporadically.this has been going on for several weeks had ballast tested socket and hood bulbs at hyrdo store and worked fine there he even switched out ballast for me 2nd time i went in.has to be in house,it's on 20 amp circuit only running light and a fan.any ideas thanks