Stiebel Eltron Tempra tankless water heater internal view

Use the numbers on the picture to reference the internal components of the Stiebel Eltron water heater with the description of each component below. While the model pictured is a Tempra 24, all models share the same components. The difference between the various models is determined by the number and size of the heating modules.

Electronic Control Module Electronic Control Module
Sophisticated microprocessor-controlled electronics adjust the power output of the heating elements based on flow rate and incoming water temperature to precisely regulate the output water temp.
Heating Module Heating Module
The muscle of the system! A series of very high output heating modules (up to 3, depending on model) are used to heat the water as it passes through the heating chambers of the water heater. The Heating chambers are manufactured with copper - no cheap plastics here!
Flow Sensor Flow Sensor
A sophisticated flow rate sensor delivers important data to the microprocessor on a continuous basis - this data is used by the microprocessor to calculate the power level of the heating modules that is necessary to heat the water to the set temperature.
Safety Thermal cut-off Safety Thermal cut-off
Safety first! Each heating element is protected by thermal limit switch, a back-up safety feature that will automatically turn off the heating module if a potentially unsafe output water temperature is reached. This reduces the risk of scalding injuries for children and the elderly, and protects the unit from damage if the microprocessor-based thermostatic control fails.
Temperature Selector Temperature Selector
Set it and forget it - use the simple dial control to raise or lower the temperature setting. Tempra Plus as well as Tempra 36, 20, 15, and 12 models are equipped with a digital temperature setting display. The temperature can be set at any level from 86F (30C) & 125F (52C) [up to 140F or 60C on Plus Models and Tempra 24].
Temperature Sensors Temperature Sensors
Working in conjunction with the flow sensor, a series of temperature sensors deliver important data to the microprocessor on a continuous basis so that the unit can acurately maintain the set output water temperature.
Wiring Block Wiring Block
Convenient terminal blocks are provided to ensure a quick, simple, and safe installation.
Flow Control Flow Control
Exclusive to Tempra Plus models, the dynamic Advanced Flow Control system will adjust the flow rate of the water if the microprocessor detects that the flow rate exceeds the capacity of the system. The result is the most precise temperature control of any tankless water heater on the market today! Ideal for applications where simultaneous hot water applications occasionally exceed normal model flow rate capacities.
Sturdy Hinged Steel Case Sturdy Hinged Steel Case
All Stiebel Eltron Tempra and Tempra Plus Series water heaters are housed in a sturdy steel case with built-in wall mounting brackets. Many competitors use flimsy light-gauge aluminum cases or even plastics. Tempra Plus and Tempra 24 models feature a convenient hinged case for easy access.
Water Filter and Shut-off Valve Inlet Water Filter
The inlet water pipe includes a small screen filter that ensures that no debris is able to enter the system. This filter should be periodically cleaned for optimal flow performance. In most cases, this need only be done once every few years, but the exact frequency will depend on your water quality.

Stiebel Eltron Tempra Plus tankless water heater - inside view

*Note: The Tempra 36 Plus and Tempra 29 Plus have 3 heating modules (not pictured).

Stiebel Eltron Tempra B tankless water heater - inside view

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