Operating instructions

4Operating instructions

4.1Initial filling instructions

Before proceeding with the operation of the heater make sure that the system is filled with water:

BTurn off power supply to heater.

BOpen the cold water inlet supply to the heater fully.

BOpen a hot water faucet to permit the water to fill the heater and the piping and to eliminate the air trapped in the system.

BClose the hot water faucet after the water flows freely and all the air has escaped from the system. Turn on power supply to heater. The water heater is now ready to operate.

Fig. 31

4On/Off button

5 Reset button

6 Recirculation water temperature selector

7 LED - (ON) warning light (blinks during lock-out error)

8 Domestic hot water temperature selector

27 Digital display

4.2For your safety read before operating your water heater

Warning: If you do not follow these instructions exactly, a fire or explosion may result causing property damage, personal injury or loss of life.

WHAT TO DO IF YOU SMELL GAS

BDo not try to operate any appliance.

BDo not touch any electric switch; do not use any phone in your building.

BImmediately call your gas supplier from a neighbors phone. Follow the gas supplier’s instructions.

BIf you cannot reach your gas supplier, call the fire department.

BUse only your hand to press the on/off control switch. Never use tools. Follow these instructions exactly. If control switch is jammed, close the gas supply and call a qualified service technician. Attempted forceful repair may result in a fire or explosion.

BDo not use this appliance if any part has been under water. Immediately call a qualified service technician to inspect the appliance and to replace any part of the control system and any gas control which has been under water.

4.3Startup instructions

B1. STOP! Read the previous safety information.

B2. The gas valve must be shut off by putting the ON/ OFF switch to position OFF. Wait five (5) minutes to clear out any gas. If you smell gas, STOP! Follow the safety information in Chapter 4.2 above. If you do not smell gas, go to the next step.

B3. This appliance is equipped with electronic ignition for lighting the main burners. When turning the heater on, follow these instructions exactly.

B4. Press the ON/OFF switch to the ON position. In this position, the water heater is ready to use.

B 5. Connect tank Aquastat to the TT (thermostat) connection on the heater's printed circuit board. (Fig. 6, page 8). Close circuit on Aquastat to activate heater.

B6. The burners will remain on until the heat demand is met.

NOTE: upon installation or after

igas line work has been done, air in the gas line may cause a lockout error. Reset the unit (Fig. 31, pos. 5). The heater will reattempt ignition.

When the heater is in operation you may hear its induced draft vent fan and burner operating. After a call for heat is satisfied, the fan will continue to operate for up to 5 seconds to exhaust all flue gases.

TO TURN OFF GAS TO APPLIANCE

BTurn off the manual gas shut off on the supply line to the heater and set the ON/OFF switch to the OFF position. Note: a manual gas shut off valve is not supplied with the heater.

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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.