Power, Freeze protection | Bosch Appliances GWH-345/450-ESR-L

Operating instructions

4.4Power

To start the appliance:

Bpress the ON/OFF button. LED (fig. 31) goes orange.

When the burner is working, the LCD display shows the symbol .

Fig. 32

Off

To shut down the appliance:

Bpress the ON/OFF switch to OFF position.

4.5Recirculating water temperature

Water temperature can be regulated in a range of 113°F to 190°F. The heater modulates the burner flame according to current demand selected on left knob.

To select water temperature:

BRotate recirculating water temperature selector in order to change heating recirculating temperature (ranging from 113°F to 190°F).

The display will show this symbol and blink the

selected temperature.

If the burner is on, symbol goes ON.

Fig. 33 Recirculating water temperature adjustment

4.6Temperature and hot water flow

Choose one the following:

•If using a tank mounted Aquastat, set temperature on Aquastat control (left knob should be in maximum position).

•To activate and use the appliance domestic temperature dial, a 12 kOhm thermistor is required (part number 8 714 500 034) (See 2.6, Page 8 for wiring diagram).

BConnect the 12kOhm thermistor blue wire to the DHW NTC terminal block.

Install the sensor in the tank well.

Hot water temperature can be set from 50°F to 158°F

using hot water temperature selector (Fig. 34).

Fig. 34 Hot water temperature adjustment

Thermostat	DHW
knob position	temp.

Min.	approx. 50°F (10°C)

Max.	approx. 158°F (70°C)

Table 14 Domestic hot water temperature adjustment

4.7Freeze protection

BDo not disconnect the electric supply from heater.

B Do not install in unheated areas which can experience freezing temperatures.

BDo not use non-potable additives like glycol.

Freeze protection

Freeze protection is always assured by the operation of the appliance.

If the primary NTC (temperature) sensor detects temperatures 9°F below the selected temperature, the appliance starts on minimum power until the sensor reads selected temperature.

In case of minimum setpoint it will start at 41°F.

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GWH-345/450-ESR-L, GWH-345/450-ESR-N specifications

Bosch Appliances has long been recognized for its innovative and high-quality home appliances, and the GWH-345/450-ESR-N and GWH-345/450-ESR-L water heaters are no exception. These models offer exceptional efficiency and reliability, making them ideal choices for modern households seeking dependable water heating solutions.

One of the standout features of the GWH-345/450-ESR series is their impressive energy efficiency. Engineered with cutting-edge technology, these units operate with high thermal efficiency ratings. This not only translates to reduced energy bills for consumers but also supports environmentally friendly practices by minimizing energy consumption. The tankless design eliminates the need for a storage tank, providing hot water on demand while ensuring that no energy is wasted in heating and re-heating stored water.

Both models come equipped with advanced safety features. The integrated combustion management system ensures precise control of the combustion process, which not only enhances heating efficiency but also reduces the risk of overheating. Additionally, the built-in safety mechanisms, such as flame failure protection and overheat protection, provide consumers with peace of mind knowing their home is protected.

These Bosch water heaters also feature a user-friendly digital display that allows for easy temperature adjustment and monitoring. The intuitive interface enables users to set their desired water temperature with precision, ensuring comfort and convenience. Furthermore, these models are designed for quiet operation, making them suitable for installation in various locations within the home without causing disruptive noise.

The construction of the GWH-345/450-ESR-N and GWH-345/450-ESR-L models is robust, featuring high-quality materials that ensure durability and longevity. The compact and sleek design allows for flexible installation options, even in smaller spaces. With a variety of venting options available, including direct vent and power vent configurations, these heaters can fit seamlessly into different home layouts.

In summary, Bosch Appliances GWH-345/450-ESR-N and GWH-345/450-ESR-L models represent the pinnacle of modern water heating technology. With their energy-efficient performance, advanced safety features, user-friendly controls, and durable construction, these water heaters are designed to meet the demands of today’s homes while delivering reliable hot water whenever needed. These innovative appliances reinforce Bosch's reputation as a leader in home heating solutions, ensuring that customers can enjoy hot water with confidence and peace of mind.