Electrical Requirements - Stiebel Eltron tankless water heaters

tankless installation notice

Before purchasing a Stiebel Entron, or any other electric tankless water heater, please ensure that your home has sufficient electrical capacity for your desired model, or that you have taken note of any upgrades that may be required.

Please see the following chart for electrical requirements:

Model Recommended
Maximum Amperage
@ 240 V
Maximum Amperage
@ 208 V
Recommended Household
Electrical Service
Recommended Minimum
Wire Gauge
Tempra 36 3 x 50 AMPS * 150 AMPS 132 AMPS 300 AMPS 3 x #6 AWG Copper *
Tempra 29 3 x 40 AMPS * 120 AMPS 105 AMPS 200 AMPS 3 x #8 AWG Copper *
Tempra 24 2 x 50 AMPS * 100 AMPS 88 AMPS 150 AMPS 2 x #6 AWG Copper *
Tempra 20 2 x 40 AMPS * 80 AMPS 70 AMPS 125 AMPS 2 x #8 AWG Copper *
Tempra 15 2 x 30 AMPS * 60 AMPS 52 AMPS 100 AMPS 2 x #10 AWG Copper *
Tempra 12 1 x 50 AMPS * 50 AMPS 44 AMPS 100 AMPS 1 x #6 AWG Copper *

* Breaker size and wire gauge must meet all applicable local, state, provincial, and national electrical codes for your area - these are only guidelines that will apply to most installations. Some codes require use of electrical sub-panel for installation, especially when heater is not mounted within line-of-sight of the main electrical panel. Wiring should be sized to maintain a voltage drop of less than 3% under load. Please consult your electrician for more details.

The above specifications are only guidelines. If your home is already equipped with a large number of electrical appliances, you may require a larger electrical service than the one recommended above. Please consult an electrician before placing an order.

If your home does not have the minimum household electrical service as specified for your desired model, you can still purchase a Stiebel Eltron tankless water heater, however, upgrades to your electrical service will likely be required. It is recommended that you consult your certified electrician for a quote, prior to purchasing.

Please be aware that uninstalled units returned due to a home that has inadequate electrical service may subject to a re-stocking fee. Please see our POLICIES page for more details.

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