The Bible never mentions temple servants
outside the books of Ezra and Nehemiah (with the exception of 1 Chronicles 9:2). From Ezra 8:20 we learn that David had set [them] apart to attend the Levites.
Precisely how they attended the Levites, though, is difficult to ascertain. To repair a section of the wall they obviously had to leave their (undetermined) task alongside the Levites in exchange for lifting heavy stones back into place on the wall. Their labours on the wall were done under the leadership of Pedaiah.
26 and the temple servants living on Ophel repaired to a point opposite the Water Gate on the east and the projecting tower.