A fitting assembly may seal a wire within a tube to inhibit ingress of fluid outside the tube into the tube and into contact with the wire. The fitting assembly may optionally include a body and a nut, with a part of the nut received within the body. The nut may be threadedly connected to the body, such that threading and/or unthreading the nut translates the part of the nut within the body. Optionally, the nut may include a ring extension that is received within a ring cavity of the body, and an interfacing between the ring extension and the ring cavity may create a seal to inhibit leaking of the fluid past the seal. A method of sealing a wire within a tube may comprise positioning a tube with a wire therein within such a fitting assembly.