Exhibit 23.1

KPMG LLP
Suite 1900
111 Congress Avenue
Austin, TX 78701-4091

Consent of Independent Registered Public Accounting Firm

We consent to the incorporation by reference in the registration statements (No. 333-291117) on Form S-3 and (Nos. 333-239224, 333-239707, and 333-256466) on Form S-8 of CECO Environmental Corp. of our reports dated May 21, 2026, with respect to the consolidated financial statements of Thermon Group Holdings, Inc. and the effectiveness of internal control over financial reporting.

 /s/ KPMG LLP

Austin, Texas

May 29, 2026

KPMG LLP, a Delaware limited liability partnership, and its subsidiaries are part of
the KPMG global organization of independent member firms affiliated with KPMG
International Limited, a private English company limited by guarantee.