The Rheem RTG20285 Cross Over Valve Kit is designed to enable recirculation in hot water systems where dedicated return lines are not present. Installed at the fixture furthest from the water heater, typically under a sink, this thermostatically controlled valve allows cold water lines to act as a temporary return path during pump operation, significantly reducing hot water delivery times.
This component is suitable for use in residential retrofit applications where plumbing modifications are limited. It is compatible with recirculation-enabled Rheem tankless water heaters and is part of Rheem’s integrated comfort delivery systems.
Primary Function
Type: Thermostatic crossover valve
Operation: Opens below ~95°F to allow return flow; closes automatically at approximately 105°F to maintain hot water availability at the fixture
Placement: At the furthest fixture (typically under a lavatory or kitchen sink)
System Compatibility
Compatible with Rheem tankless gas water heaters equipped with recirculation programming
Can be paired with an external recirculation pump where a dedicated return line is not installed
Included Components
Crossover valve body with integrated thermostatic element
Supply line fittings
Mounting and installation hardware
Installation Overview
The RTG20285 is intended for under-sink installation at the terminal fixture. Installation requires cold and hot water shutoff, connection to the angle stops or supply lines, and secure attachment of the valve to existing piping. No electrical wiring is required. This product should be installed by a qualified plumber to ensure correct operation and compliance with code requirements.
Incorrect installation may result in poor circulation performance, premature valve failure, or unexpected temperature swings.
Use Case Scenarios
Residential homes without dedicated hot water return piping
Retrofit solutions for existing tankless systems
Improving hot water response time at distant fixtures
Performance Notes
Valve opens automatically when hot water drops below set temperature threshold (~95°F)
Closes once threshold (~105°F) is reached, maintaining hot water at the fixture and preventing continuous loop operation
Reduces water waste and improves user comfort without requiring structural plumbing changes
Additional Considerations
May require multiple valves in large homes with multiple remote fixtures
System performance depends on pump flow rate and heater recirculation settings
Do not install in systems with dedicated return piping