16 Pa.C.S. § 12308: Action by deputies.

(a) Appointment.--

(1) If a county officer is authorized or required to appoint a deputy, the deputy or principal deputy, if there is more than one, shall, during the necessary or temporary absence of the deputy's principal, perform each duty of the principal and, in case of a vacancy or under section 12301(b) (relating to elected officers), until a successor is qualified.

(2) If fulfilling the duties under paragraph (1) for a vacancy in a county of the third, fourth, fifth, sixth, seventh or eighth class, a deputy shall receive the salary provided under law for the principal or the salary provided for the deputy, whichever is greater.

(b) Oath.--A person temporarily succeeding to a county office by reason of the death, resignation or removal of the duly elected or appointed officer, may not execute any of the duties of the office until the person has taken the oath and filed the bond required of the principal officer.