Bosch Electric Tankless
Water Heaters - Tronic
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Explore Bosch electric tankless water heaters Tronic 5000/6000, designed for residential and light commercial applications, and for the point-of-use service and whole-house water heating.

Bosch electric tankless water heaters in North America are known as Tronic and are designed for heating potable water on demand in residential and commercial applications. Tronic series is recommended for areas and homes where the electricity is the only option or preferred energy source. And due to its small, compact and lightweight design, they are the preferable unit for kitchen and bath installations.

The advanced design includes the pulse-modulating elements resulting in the improved control and efficiency, and due to the reduced scale build-up, the performance is maximized. The Tronic group replaced the discontinued PowerStar models.

Tronic 5000C Pro/6000C

bosch tronic 5000

Bosch electric tankless water heaters from Tronic 6000 C series are found as WH17 and WH27 models, which are almost identical units, where larger WH27 model provides more hot water. Both models use two heater modules.

Tronic 5000 C offers only one model WH36 which is the largest of all electric tankless water heaters from Bosch. WH36 is designed to work with three heating modules, which results in the total power of 36 kW and water flow rate of up to 5.4 GPM.
All the models are designed as the whole-house tankless water heaters that provide hot water on demand and in continuous supply from one to three fixtures.

In order to provide a constant hot water temperature, which is resulting in better comfort and user experience, they use the thermostatic modulation.

The front located knob allows an easy and accurate temperature change between 95 F and 131 F while the LED display monitoring and control.
The electronic control PCB allows monitoring of the water flow rate and incoming water temperature, which then uses the required number of the heating elements to provide desired or set temperature.
With the temperature rise of 45 F, WH27 can provide approximately 3.5 gallons of hot water per minute, while WH17 less - 2.3 GPM. Also, the bigger model needs higher water flow rate for the heater's activation, 0.8 GPM vs. 0.6 GPM.

Tronic WH36 model comes with the power of 36 kW while the second largest WH27 model has the input of approximately 27 KW, making them both great for colder and warmer regions, while the smallest model WH17 gives approximately 17 kW and is recommended for southern regions mainly, where the incoming water is not as cold. Due to its difference in the voltage and amps requirements (80 A vs. 120 A), different size breakers are needed.

The thermal efficiency is for all high, 97%, and such a high energy efficiency shows that the heat loss from the heating elements is very low, most of its input goes toward heating the water. The units work on 240 V, but can also work on 220 V and 208 V but will have the reduced power output.

Thanks to the ¾” water connections, the units can easily deal with the high water flow and hot water tank replacement.

Tronic 3000C Pro

bosch tronic 3000

Bosch electric tankless water heaters from Tronic 3000 are point-of-use models that are smaller than the upper Tronic 5000 units and are used only for one sink, most of the time kitchen or bathroom sink, but can be used in the garage or office. They can be used in residential and light commercial applications.

Tronic 3000 uses the tube-shape heating elements made of copper, which heats water instantaneously and transfer the energy directly to the water with the minimal energy loss, making the energy efficiency very high, 99%. The heat exchanger is protected from the excessive water temperature of over 194 F, so it uses the thermal cut-out that needs to be manually reset if it trips.

Due to the simple design and use of electricity, they barely require any maintenance.
Model US3 US6 US7 US9 US12
Max. Input kW 3.4 6.0 7.2 9.5 12
Max. Volts V 120 277 240 240 240
Max. Amps 30 25 30 40 50
Activation Flow Rate GPM 0.5 0.5 0.75 0.75 0.6
Max. Flow Rate GPM
Temp. rise of 55 F
0.4 0.7 0.9 1.2 1.5

The small unit size of maximum 12” x 6” x 3" allows Tronic 3000 to occupy minimal indoor space, making it perfect for hard to reach locations and tight spots. Tronic 3000 is installed by hanging it on the wall either vertically or horizontally, except the US12 model. The US12 model is also the largest model in this series – highest power and water flow rate.

The specs of all electric water heaters are shown in the table above, but keep in mind that models can work with the lower voltage, which also reduces the output. All the models are utilizing the mechanical temperature control, while US12 thermostatic - the unit will switch the elements ON and OFF and maintain the constant temperature of the outgoing water. The Tronic US12 model uses the adjustment spindle (behind the nameplate) for the temperature adjustments. Other water heaters use the Power Selector Screw to set the power to Low (when one heating element operates) or Hi (both heating elements are ON).

Bosch electric tankless water heaters are ideal for homes, garages, small offices, apartments, cottages, and places where it is hard to get hot water from the main water heater, and distant fixtures. The Tronic series eliminates the need for long piping, venting and water storage, it minimizes sediment build up inside the heater and energy loss, therefore, saving you time and money. These are indoor units and must not be installed in the rooms where there is a chance of freezing.

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Tronic 3000 Series (US12)

Tronic 3000 Series (US3, US6, US7, US9)

Tronic 5000 Series (WH17 / WH 27)

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