are all heater elements replacable

[Kathio]

I have a balboa 4kw heater thats 15" x 2" x 2" on a cal spa. I haven't taken the heater tube off yet so i don't know if i can replace just the element or if i have to replace whole tube. Any help would be great. thanks in advance

[Mary]

Most Balboa heaters have replacable elements. The non replacable elements would be welded in the manifold, the replacable elements would have two bolts holding the element in place which would be visable.