808440-2 — Dual Bypass Valve Repair & Overhaul

Component Overview

A dual bypass valve is a pneumatic control valve in the air-management system that regulates two parallel flow paths or selectively diverts air around a component such as a heat exchanger or pack section to manage temperature and flow. Typically incorporating dual butterfly or poppet elements with a shared actuator and control reference, it modulates how much air bypasses versus passes through, balancing conditioning performance against thermal and pressure constraints. Its primary function is coordinated flow distribution and temperature trimming. In service it experiences butterfly-shaft and bushing wear, actuator and linkage backlash, seal and seat degradation, spring fatigue, and contamination or coking from hot bleed air, leading to leakage, sluggish or inaccurate modulation, and position error. Overhaul restores shafts, bushings, seals, and actuation, then verifies calibrated travel, leakage, and response.

Aircraft Application

Part number 808440-2 (Dual Bypass Valve) is installed on the Bombardier CRJ200. QTC supports operators and MROs servicing this platform with certified repair and overhaul.

Our Repair Capability

QTC repairs and overhauls 808440-2 to the original manufacturer's specifications under our FAA and EASA Part 145 approvals. Our team — including former OEM pneumatic & air management engineers — performs teardown, inspection, cleaning, component replacement, functional testing, and certification, returning a serviceable unit with the appropriate airworthiness release. We also develop repairs for rejected and beyond-economic-repair (BER) hardware.

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Related Parts

Other dual bypass valve part numbers we repair — view all Dual Bypass Valve parts →

Frequently Asked Questions