779215-1 — Dual Heat Exchanger Repair & Overhaul

Component Overview

A dual heat exchanger is a combined heat-transfer unit that integrates two heat exchange stages, typically primary and secondary air-to-air cores, into a single assembly within the air cycle cooling path. Hot bleed or compressed air is progressively cooled by ram or fan air passing across finned cores, conditioning the air before and after the air cycle machine to support cabin temperature control. Combining stages saves weight and installation volume. Common degradation modes include fatigue and thermal-stress cracking at braze joints, fins, and tanks, internal leakage between the hot and cold passages, external core leakage, and fin fouling, corrosion, or erosion that reduce thermal effectiveness and increase pressure drop. These conditions drive leak and performance testing, core repair, and overhaul.

Aircraft Application

Part number 779215-1 (Dual Heat Exchanger) is installed on the Saab 340. QTC supports operators and MROs servicing this platform with certified repair and overhaul.

Our Repair Capability

QTC repairs and overhauls 779215-1 to the original manufacturer's specifications under our FAA and EASA Part 145 approvals. Our team — including former OEM heat transfer 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 heat exchanger part numbers we repair — view all Dual Heat Exchanger parts →

Frequently Asked Questions