System Overview

The ODB Engine / Hydronic Dual Heat Exchange System connects the vehicle’s engine cooling system to the existing hydronic heating system through a dedicated coolant-to-coolant heat exchanger and auxiliary circulation pump.

This integration allows heat to transfer between the engine and hydronic heating loop while preserving the original operation of the hydronic system.

How It Works

The system introduces a single engine-to-hydronic heat exchanger that transfers heat between the engine coolant circuit and the hydronic heating loop.

An auxiliary vane-style circulation pump, controlled by a dash-mounted switch, circulates engine coolant through the heat exchanger when heat transfer between systems is desired.

The hydronic system itself remains unchanged and continues to heat the cabin air and domestic water through its existing heat exchangers.

Cold Weather Benefits

This configuration enables:

• Engine preheating before cold starts
• Heat sharing between the engine and hydronic systems
• Cabin heat without extended engine idling
• Improved cold-weather operation during overnight or stationary use

Note: Component layout and plumbing may vary depending on vehicle platform and hydronic system configuration.