Stiebel Eltron Tempra Plus Review: The Benchmark of German Tankless Engineering

Imagine a world where hot water is truly on demand, endless, and consistently perfect, regardless of how many showers are running or how much laundry is being done. This isn’t a pipe dream; it’s the promise of the Stiebel Eltron Tempra Plus series. For decades, Stiebel Eltron has been a pioneer in advanced water heating technology, and their Tempra Plus models exemplify German engineering at its finest. This comprehensive review will delve into the features, performance, installation realities, and overall value of the Stiebel Eltron Tempra Plus, helping you determine if this premium tankless electric water heater is the right upgrade for your home.

The Core of German Engineering: Features of the Stiebel Eltron Tempra Plus

At the heart of the Stiebel Eltron Tempra Plus’s reputation lies a suite of sophisticated features designed to deliver an unparalleled hot water experience. These are not just add-ons but fundamental elements that set it apart in the tankless water heater market.

One of the standout innovations is the Advanced Flow Control™, an exclusive technology that ensures your hot water temperature remains constant, even if the demand momentarily exceeds the unit’s capacity. Instead of delivering colder water, the system intelligently reduces the flow slightly to maintain the precise temperature you’ve set, eliminating those unwelcome cold surprises. This dynamic adjustment is crucial for households with fluctuating hot water needs.

The unit boasts microprocessor-controlled thermostatic temperature regulation with a convenient digital display and dial selector. This allows you to set your desired output water temperature anywhere between 86°F and 140°F (30°C and 60°C) with exceptional accuracy. This precise control ensures that hot water is delivered at the perfect temperature every time a faucet is opened. The Tempra Plus models are also among the few tankless water heaters offering true thermostatic temperature control and full power-modulation, adapting to changes in both incoming water temperature and flow rate to maintain your set temperature.

Further enhancing its efficiency is the self-modulating power technology. This smart feature continuously monitors incoming water temperature and adjusts the power output automatically, using only the smallest amount of electricity necessary to heat the water to your desired setting. This eliminates standby heat loss, a common inefficiency in traditional tank water heaters that continuously heat stored water.

Beyond its internal workings, the Stiebel Eltron Tempra Plus showcases a compact and sleek design, making it significantly smaller than conventional tank heaters. This space-saving advantage allows for flexible installation, often freeing up valuable utility space. Crucially, as an electric unit, it requires no venting, further simplifying installation and offering more placement options. Its robust construction features a sturdy steel housing with integrated wall mounting brackets, distinguishing it from competitors that often use lighter plastics. This build quality contributes to its seismic-proof construction and whisper-quiet operation, as it contains no mechanical switches.

Stiebel Eltron Tempra Plus tankless water heater, showcasing its compact size and sleek design.

Performance Under Pressure: The German Engineering Test

When it comes to real-world performance, the Stiebel Eltron Tempra Plus truly shines, living up to the promise of its German engineering. Users consistently report high marks for accurate water temperature output and water flow, thanks to its advanced control systems.

The unit offers an unlimited supply of hot water, responding directly to your demand without interruption. This means multiple showers can run consecutively without the water turning cold, a significant advantage over tank heaters that can quickly deplete their stored hot water. The Tempra Plus maintains a steady output temperature even when flow rates vary, ensuring a consistent and comfortable experience.

From an energy efficiency and cost savings perspective, the Tempra Plus is impressive. With an energy efficiency rating of 99% or higher, it drastically reduces energy consumption compared to traditional tank water heaters. By heating water only as it’s needed, it eliminates the 15-20% energy loss associated with standby heat in conventional tanks. This can translate to typical savings of 15-20% over electric tank water heaters and even up to 50% over older conventional systems on your hot water heating costs.

The Tempra Plus series comes in various kilowatt (kW) models (e.g., 12, 15, 20, 24, 29, 36) to cater to different household sizes, hot water demands, and regional incoming water temperatures. For example, the Tempra 24 Plus is suitable for northern regions or higher flow rates, while the Tempra 36 Plus is ideal for extreme north climates or very high flow applications, capable of delivering up to 4 gallons per minute (GPM) with a significant temperature rise. This versatility ensures that you can select a model perfectly sized for your specific needs, maximizing both performance and efficiency.

Visual comparison of Stiebel Eltron Tempra Plus models (12, 24, 36) highlighting diverse household applications.

Installation & Electrical Considerations: A Critical Look

While the Stiebel Eltron Tempra Plus offers exceptional performance, its installation requires careful consideration, particularly regarding electrical infrastructure. It is unequivocally stated that the unit must be installed by a licensed electrician and plumber, adhering to all national, state, and local plumbing and electrical codes. This isn’t merely a recommendation; it’s a safety and warranty requirement.

The most significant consideration is the substantial electrical requirements. These units draw a considerable amount of power, which can be a major hurdle, especially for older homes. For instance, the Tempra 24 Plus typically requires two dedicated 60-amp circuits and a minimum recommended electric service of 150 amps. Larger models like the Tempra 29 Plus demand three 40-amp circuits and a minimum 200-amp service, while the Tempra 36 Plus needs three 50-amp circuits and a 300-amp service. If your existing electrical panel cannot handle this load, a costly panel upgrade may be necessary, which can add significantly to the overall investment. It is crucial to check your home’s electrical capacity before purchasing.

In terms of plumbing connections, the units typically feature standard 3/4″ NPT fittings for both cold water inlet and hot water outlet. Installation is in a vertical position with water fittings pointing downward. An important benefit of tankless units like the Tempra Plus is their seismic-proof construction, meaning they are not subject to the same building codes as tank water heaters, which often require preventative construction. The cold water inlet usually includes a filter screen that requires periodic cleaning to ensure consistent water flow.

Living with the Tempra Plus: Pros, Cons, and Maintenance

Choosing a Stiebel Eltron Tempra Plus involves weighing its many advantages against a few key considerations.

Pros:

• Superior Temperature Consistency and Endless Hot Water: The Advanced Flow Control™ and microprocessor-based regulation virtually guarantee a continuous supply of hot water at your desired temperature, even during peak demand.
• High Energy Efficiency and Long-Term Savings: With 99%+ energy efficiency and the elimination of standby heat loss, you can expect significant reductions in your electric bill compared to traditional tank heaters.
• Compact, Space-Saving, No Venting: Its sleek design frees up valuable floor space and offers greater flexibility for installation locations, as it doesn’t require complex venting.
• Durable German Engineering: Stiebel Eltron has a long-standing reputation for quality and reliability, promising a longer service life than many conventional units.
• Quiet Operation: The absence of mechanical switches ensures the unit operates silently.

Cons:

• High Upfront Cost and Demanding Electrical Requirements: The initial purchase price can be higher than some tank alternatives, and the need for significant electrical upgrades in older homes can substantially increase the total cost of ownership.
• Potential for Circuit Board Issues: While robust, some anecdotal reports mention circuit board failures following power outages, suggesting that a whole-house surge protector might be a wise additional investment.

Maintenance Tips:
Stiebel Eltron Tempra Plus tankless water heaters are designed for a very long service life and generally require minimal maintenance. However, to ensure optimal performance and longevity, periodic checks are recommended:

• Clean the Inlet Filter Screen: The cold water inlet contains a filter screen that should be cleaned from time to time to prevent restricted water flow.
• Check Faucet Aerators and Shower Heads: Periodically remove scale and dirt buildup in your fixtures to maintain consistent water flow.
• Descaling (If Needed): In areas with hard water, scale can build up on heating elements. While less prone than some other types, descaling may be required every few years to maintain efficiency.
• Thermal Safety Reset: In case of a tripped thermal safety cut-out (often due to overheating or power issues), the unit has reset buttons located on top of each copper heating vessel, accessible after safely disconnecting power and removing the cover.

Is the Stiebel Eltron Tempra Plus Right for You?

The Stiebel Eltron Tempra Plus series is an exceptional choice for homeowners seeking a premium, highly efficient, and reliable tankless electric water heating solution. It particularly shines for:

• New Construction or Major Renovations: Where electrical infrastructure can be designed to easily accommodate its power requirements.
• Homeowners Prioritizing Consistent Hot Water: Those who value endless hot water and stable temperatures for multiple simultaneous uses.
• Individuals Seeking Long-Term Energy Savings: The high efficiency translates into substantial savings on utility bills over the unit’s extended lifespan.
• Space-Conscious Buyers: Its compact, vent-free design is perfect for homes where space is at a premium.

However, you might want to reconsider if you live in an older home with an outdated electrical panel and a limited budget for significant electrical upgrades. The initial investment in both the unit and potential electrical work can be substantial. For those with specific concerns about power surges, an additional whole-home surge protector could offer peace of mind.

Ultimately, the Stiebel Eltron Tempra Plus represents a significant investment in comfort, efficiency, and German-engineered reliability. For the right home, it’s a decision that will provide years of consistent, on-demand hot water, silently and efficiently.

Frequently Asked Questions

What is Advanced Flow Control™?

Advanced Flow Control™ is an exclusive technology in Stiebel Eltron Tempra Plus models that automatically adjusts the water flow slightly if hot water demand exceeds the heater’s capacity, ensuring a consistent output temperature rather than delivering colder water.

How much electricity does a Stiebel Eltron Tempra Plus use?

The actual electricity consumption varies by model (kW rating) and usage habits. However, Tempra Plus units are over 99% energy efficient, significantly reducing energy usage compared to conventional tank heaters by only heating water when needed and eliminating standby losses.

Can I install the Stiebel Eltron Tempra Plus myself?

No, the Stiebel Eltron Tempra Plus must be installed by a licensed electrician and plumber. This ensures compliance with all local codes, proper electrical connections, and safe operation. Attempting DIY installation can void the warranty and pose safety risks.

What are common Tempra Plus troubleshooting issues?

Common issues include temperature fluctuations, error codes, and low water pressure. Many minor glitches can be resolved by checking the digital display for codes, resetting the unit, or cleaning the inlet filter and faucet aerators.

How often should I maintain my Tempra Plus?

The unit itself does not require regular maintenance, but it is recommended to periodically clean the inlet filter screen and check faucet aerators and shower heads for scale and dirt buildup to ensure consistent water flow. In hard water areas, descaling the heating elements might be needed every few years by a professional.