When people think of plumber, they might only think of toilets and sinks. I often associate the profession with those things too, but professional plumbing services do so much more than that.
They can also handle gas line problems, septic tank issues, pipes bursting, water heater replacement and repair, air conditioners, and much more.
No two services are alike and some only specialize in one area as opposed to the many that offer basic services.
Either way, I would not hesitate to call them if I had any kind of plumbing issue. I know that they could get it fixed the right way. They could also get it fixed right the first time.