231 Pa. Code § 3117 : RULES OF CIVIL PROCEDURE — GENERAL — JUDGMENTS — ENFORCEMENT OF MONEY JUDGMENTS FOR THE PAYMENT OF MONEY — Discovery in aid of execution

(a) Plaintiff at any time after judgment, before or after the issuance of a writ of execution, may, for the purpose of discovery of assets of the defendant, take the testimony of any person, including a defendant or a garnishee, upon oral examination or written interrogatories as provided by the rules relating to Depositions and Discovery. The prothonotary of the county in which judgment has been entered or of the county within this Commonwealth where the deposition is to be taken, shall issue a subpoena to testify.
(b) All reasonable expenses in connection with the discovery may be taxed against the defendant as costs if it is ascertained by the discovery proceedings that the defendant has property liable to execution.

231 Pa. Code § 3117