Appellants contend the lower court erred in refusing to open a default judgment. We disagree and, accordingly, affirm.
On January 30, 1981, appellee filed a complaint seeking to foreclose on appellants’ note. Appellants did not answer within the requisite twenty days, and appellee filed a ten-day notice of its intent to seek default judgment. Pa.R. Civ.P. 237.1. Appellants then requested and received two extensions. Appellants’ counsel referred to the second extension in a letter to appellee reading: “Unfortunately I have run into a problem in getting an answer up to you. I would expect to have it up to you by next Thursday. If there are any problems with this, let me know.” Letter from John J. Dean to Thomas W. King III (March 12, 1981). See N.T. at 13. Appellants did not file the answer by Thursday, and a default judgment was entered the following Tuesday, March 24. Appellants petitioned to open judgment on April 28, 1981. After a hearing, the petition was denied, and this appeal followed.
Appellants argue that their extension letter was so general as to require further notice under Pa.R.Civ.P. 237.1 before a default judgment. We disagree. Informal written extensions are permitted under Rule 237.1, but they “should be sufficiently specific to avoid argument over [their] terms.” Explanatory note to Pa.R.Civ.P. 237.1. Written agreements “couched in general language, without specifying a fixed date for compliance” entitle a party to an additional ten-day notice before judgment can be taken. Id. Consistent with the principle that written agreements are construed against the party preparing them, Central Transportation, Inc. v. Board of Assessment Appeals of *324Cambria County, 490 Pa. 486, 417 A.2d 144 (1980), counsel who requests an extension and specifies its length cannot excuse a default by claiming misapprehension. Horan v. R.S. Cook & Associates, 287 Pa.Superior Ct. 265, 430 A.2d 278 (1981). The letter sent by appellants’ counsel indicated a specific day for submission of an answer, and thus, having failed to meet these criteria, did not entitle appellants to a second notice.
Appellants argue also that their default was excusable, they have a meritorious defense, and their petition to open was timely filed. We disagree.
The well-established rule for opening a default judgment in an assumpsit case requires the existence of three factors: (1) a promptly filed petition; (2) a seemingly meritorious defense; and (3) an excusable reason for the default. Balk v. Ford Motor Co., 446 Pa. 137, 285 A.2d 128 (1971).* The existence of these factors depends on equitable considerations, including a weighing of the prejudices to each party arising from opening, or refusing to open, judgment. Toplovich v. Spitman, 239 Pa.Superior Ct. 327, 361 A.2d 425 (1976). Accord, Provident Credit Corp. v. Young, 300 Pa.Superior Ct. 117, 446 A.2d 257 (1982).
Appellants give no reason for waiting over thirty days before filing a petition to open judgment. Their only explanation for the default was counsel’s preoccupation with other business and misapprehension of the deadline, an unacceptable excuse. See Horan v. R.S. Cook & Associates, supra. Because appellants’ defense can be raised in a separate proceeding, (1031 Pa.R.Civ.P.; Sobol v. Will Allen Builders, Inc., 244 Pa.Superior Ct. 486, 368 A.2d 825 (1976)), the equities do not weigh in favor of opening judgment. Thus, because the petition was not timely filed, *325the default was not excusable, and the appellants’ defense does not warrant opening judgment, we affirm the lower court’s denial of appellants’ petition.
Affirmed.
JOHNSON, J., concurs in the result. SPAETH, J., files a dissenting opinion.The lower court based its decision not to open judgment on appellee’s compliance with Rule 237.1. Although this rule was intended to eliminate default judgments taken without prior notice to the opposing party, it does not change or eliminate the test for opening default judgments. Since the elements of the test were argued below, we will decide this case on the merits.