Once Gas Pressure is adequate | Bosch Appliances GWH 2400 ES NG

Maintenance and service

adjusting CO2 until pressure is at or above these levels, but not to exceed 10.5” WC for Natural Gas and 13” WC for Propane.

A. Once Gas Pressure is adequate

BPress ON/OFF button to turn off the heater.

BRemove brass flat head screw on the exhaust collar as seen in Fig. 53.

BInsert CO2 analyzer probe into the measuring port. The tip of the probe should be in the center of the flue pipe (approx 1.5" inserted). Avoid air gaps between probe and measuring port as they can alter readings.

Fig. 53 Measuring port

BWhile holding the Program (P) button in, press the ON/OFF button to turn ON the heater (see Fig. 54). As soon as ‘188’ flashes on the display, release the Program button. The display should now read P2.

Press button until “P1” appears on display.

Fig. 54

B. Measuring CO2 (combustion cover must be installed):

BOpen all hot water taps to achieve a flow rate of at least 6 gallons per minute. (1 tub and 2 sinks should be sufficient). If heater display reverts to P2, open

more hot water fixtures to allow sufficient flow. Press

‘ ’ until P1 reappears on the display.

B Record the CO2 reading in P1 below. (Analyzer reading may take several minutes to stabilize).

BPress the ‘ ’ button until P2 appears. Unit will ramp down to low fire and the flow should decrease.

BRecord the CO2 reading in P1 and P2 below.

P2 CO2 Reading:		% CO2

P1 CO2 Reading:		% CO2

C. Adjusting CO2:

Note: P1 adjustment will change the P2 reading. Confirm the P1 value BEFORE adjusting the P2 level.

1. If P1 CO2 level is off:

BLoosen yellow painted philips screw (1) and cover should rotate down (2) revealing a recessed brass slotted screw. Fig. 55.

B Turning the slotted screw counter clockwise will raise P1 CO2 levels and clockwise will lower P1 CO2 levels. Adjustments to the slotted screw will also change P2 CO2 levels.

BAfter bringing the P1 CO2 readings in proper range,

press the button to enter the P2 mode. Verify CO2 readings in P2 mode.

2. If P2 CO2 level is off:

BRemove yellow painted #40 Torx cover from the front of the gas valve. (Fig. 56) A plastic #40 Torx screw will be revealed.

B Turning the plastic #40 Torx screw counter clockwise will lower P2 CO2 levels and clockwise will raise P2 CO2 levels.

Note: This screw adjustment is very sensitive and should be made in small increments. It may take several minutes for readings to stabilize.

3.Verify both P1 and P2 CO2 readings are within the ranges specified in table 14. Repeat steps 1 and 2 as

necesssary until CO2 values are within the specified ranges.

4.Once CO2 values are within the specified ranges, verify the CO readings on P1 and P2 do not exceed values shown in table 14. If values exceed this limit, inspect vent system and fin coils (chapter 6.1, page 27) for blockage.

D. Returning to Service:

1.Return slotted screw cover to original position and tighten philips screw.

2.Reinstall Torx cover.

3.Remove CO2 analyzer probe and reinstall flathead screw with gasket in exhaust collar.

4.Press ON/OFF button to turn OFF the heater and then turn ON the heater.

5.Heater is ready for normal operation.

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GWH 2400 ES NG, GWH 2400 ES LP specifications

Bosch Appliances has established a reputation for delivering high-quality and innovative home solutions, and the Bosch GWH 2400 ES LP and GWH 2400 ES NG are no exceptions. These high-efficiency water heaters are designed to provide on-demand hot water, ensuring comfort and convenience for your home.

One of the standout features of the Bosch GWH 2400 ES LP (Liquid Propane) and GWH 2400 ES NG (Natural Gas) models is their compact, space-saving design. These tankless water heaters are engineered to fit in smaller spaces, making them an ideal choice for homes with limited installation areas. Despite their compact size, both models provides a powerful performance that meets the hot water needs for multiple fixtures simultaneously, such as showers, faucets, and washing machines.

These water heaters are equipped with advanced technology that enables precise temperature control. The Bosch GWH 2400 ES series utilizes a microprocessor-based control system that allows for consistent water heating, ensuring the water temperature remains stable even during high demand. The modulating gas valve further optimizes energy consumption, adjusting the flame intensity to meet the exact heating needs, thus enhancing efficiency.

In terms of safety, both the GWH 2400 ES LP and NG come with multiple safety features. These include a flame failure safeguard, overheating protection, and a built-in freeze protection system. Such features ensure both peace of mind and the longevity of the unit.

Installation is straightforward with these models, as they can be vented using standard venting materials, saving time and costs. Additionally, the units boast a low NOx emissions rating, making them environmentally friendly choices that help homeowners reduce their carbon footprint.

Maintenance is minimal, thanks to the corrosion-resistant heat exchanger which ensures durability and long service life under normal operating conditions. This factor, combined with Bosch’s renowned commitment to quality, makes these models a reliable investment for any household.

Whether you opt for the GWH 2400 ES LP or the GWH 2400 ES NG, you will experience the benefits of a powerful, efficient, and safe water heating solution tailored to your specific household needs. Bosch has truly combined technology, sustainability, and user comfort in these innovative models, solidifying their place as leaders in the home appliance market.