Here are the rules.
Rule 237.3. Relief from Judgment of Non Pros or by Default.
(a) A petition for relief from a judgment of non pros or of default entered pursuant to Rule 237.1 shall have attached thereto a copy of the complaint, preliminary objections, or answer which the petitioner seeks leave to file.
(b)(1) If the petition is filed within ten days after the entry of a judgment of non pros on the docket, the court shall open the judgment if the proposed complaint states a meritorious cause of action.
(2) If the petition is filed within ten days after the entry of a default judgment on the docket, the court shall open the judgment if one or more of the proposed preliminary objections has merit or the proposed answer states a meritorious defense.
Rule 236 requires the prothonotary to give notice of the entry of any judgment and to note in the docket the giving of the notice.
The petitioner must act with reasonable diligence to see that the petition is promptly presented to the court if required by local practice.
See Schultz v. Erie Insurance Exchange, 477 A.2d 471 (Pa. 1984) for the requirements for opening a judgment by default and Rule 3051 as to a judgment of non pros. Rule 237.3 does not change the law of opening judgments. Rather, the rule supplies two of the three requisites for opening such judgments by presupposing that a petition filed as provided by the rule is timely and with reasonable explanation or legitimate excuse for the inactivity or delay resulting in the entry of the judgment. The requirement of this rule for proceeding within ten days is not intended to set a standard for timeliness in circumstances outside this rule. See Rules 206.1 through 206.7 governing petition practice.