Bosch Appliances GWH 2400 ES NG Water Heater User Manual

6 720 608 782
Installation instructions
3.12 Measuring gas pressure
Confirm gas pressure upon installation.
Connecting manometer
B Shut off gas supply at installer supplied shutoff valve
for this water heater.
B Remove front cover and locate inlet gas pressure
measuring point (see Fig. 32).
B Loosen screw inside left test point fitting (do not
remove) and connect manometer tube to test point.
Remove screw completely if correct size tapping is
Static Pressure Test
B Turn gas supply back on.
B Record static gas pressure reading in table 11.
Operating Pressure Test
B Press ON/OFF button to turn off the appliance.
B Press and hold "Program" (P) button and press ON/
OFF button to turn appliance ON.
Fig. 31
B As soon as '188' is displayed, release "Program"
, button and the display should read P2.
B Press or until P1 appears.
Note: While in this mode the appliance will run
constantly at maximum power and allow
maximum water flow.
For inlet gas pressure adjustment consider the
following table:
B Turn on high volume of hot water flow (at least 6
gpm) and heater will ignite. If heater display reverts to
P2, open more hot water fixtures to allow sufficient
flow. Press until P1 reappears on display.
B Operate all other gas appliances on the same gas
piping system at maximum output.
B Record lowest operating gas pressure reading in
table 11.
Gas pressures lower than 3.5" W.C. for Natural Gas or
8" W.C. for LPG will result in insufficient degree rise to
the hot water being used, reduced hot water volume,
possible error code faults and must be corrected. See
Gas Connections, chapter 3.8, page 17.
Fig. 32 Gas pressure test port (left tapping)
page 28, for details)
Gas type NG LPG
3.5” WC 8” WC
Table 10 Minimum inlet gas pressure under full operation
Static Gas Pressure Reading (see Chapter 3.12)
enter here: ___________________ Date: ___________
Operating Gas Pressure Reading (see Chapter 3.12)
enter here: ___________________ Date: ___________
Table 11
Altitude above
sea level
0 - 2,000 ft
(0 - 610 m)
For operation at
above 2,000 ft
(610 m) the
ratings shall be
reduced at the
rate of 4% for
each 1,000 ft
(305 m) above
sea level
2,000 ft - 4,500 ft
(610 m - 1,372 m)
adjustment with flue
gas analyzer required See
6.4 for instructions.
Above 4,500 ft
(above 1,372 m)
Not approved
Table 12