for galvanized you want acid paste flux, commonly used by radiator shops, as opposed to rosin flux, used for tin and copper - acid flux on copper will leave harmful residues
"When we tug a single thing in nature, we find it attached to the rest of the world" ~ John Muir "When we tug a single thing on an old truck, we find it falls off" ~ me Some TF series details & TF heater pics
