Exhibit 23

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We consent to the incorporation by reference in Registration Statement Nos. 33-38534, 33-45012, 333-80159, 333-12561, 333-62475, 333-75166, 333-115429, 333-115430, 333-115432, and 333-126693 of Pentair, Inc. of our reports dated February 27, 2006, with respect to the consolidated financial statements and financial statement schedule of Pentair, Inc. and subsidiaries (which report expressed an unqualified opinion and included an explanatory paragraph relating to the Company’s change in 2005 in its method of accounting for stock-based compensation), and management’s report on the effectiveness of internal control over financial reporting, appearing in this Annual Report on Form 10-K for the year ended December 31, 2005.

Minneapolis, Minnesota

February 27, 2006