Using Tankless with a Recirculation Loop
Combining a whole house tankless water heater like a Steibel Eltron Tempra Series with a small mini-tank water heater like the Stiebel Eltron SHC Mini-Tank offers the benefits of both worlds by saving on water heating costs, reducing water usage, and providing hot water instantly at every faucet in your home.
of a recircuting system for a tankless water heater
Benefits of Tankless & Recirculation
- Minimizes the wait time for hot water
- Reduces water usage
Tips when installing a Tankless & Recirculation System
- Insulate all hot water pipes to minimize standby energy loss.
- Minimize the length of the run from the tankless water heater to the recirculation loop (maximum 5' recommended).
- Timed operation is recommended over an aquastat, with the timer programmed to recirculate in early morning and evening when demand for hot water is greatest.
- The thermostat on the mini tank and tankless water heater should be set to similar temperatures.
- Make sure to follow all local electrical and plumbing codes.
Alternative Recirculation Loop without SHC Mini-Tank
A Tempra can be plumbed directly into a recirculation loop, as illustrated below, provided that the flow rate of the loop is greater than the minimum activation flow rate of the Tempra. To cut down on energy consumption, an aquastat can be installed in the location Treturn, and cut power to the pump when the return of the loop is less than 5° - 10° below the Tempra’s set point. A timer is sometimes used as well to disable the recirculation loop during times of low use, such as the middle of the night.
This information is for illustration purposes and should not be used for actual installation without appropriate engineering and technical advice from a local properly licensed professional.
