Please follow these instructions. Failure to follow
instructions may result in:
B Damage or injury.
B Improper operation.
B Loss of warranty.
If you are unable to perform the tasks required to install
this heater properly, please contact a locally licensed
plumber or gas technician.
Please contact Bosch Water Heating with any
Proper location for installing your
Carefully select the location of the water heater. For
your safety and for proper heater operation, you must
provide combustion air to the heater and a proper
exhaust vent system.
Follow the guidelines below:
B 1. Locate the heater where venting, gas and
plumbing connections are feasible and convenient.
B 2. The hot water lines should be kept short to save
energy. Centrally locating the water heater is best. It
is always best to have hot water lines insulated.
Warning: The water in this water
heater is cold and always remains cold
except for the times that hot water is
being used. DO NOT INSTALL IN AN
AREA WHERE IT COULD FREEZE.
Drain the heater entirely if freezing
temperatures are anticipated in area
where heater is installed. See chapter
4.5 for draining instructions.
To prevent freeze damage from residual
water in the heater, introduce short
bursts of compressed air (20-40psi)
through these connections to remove
the residual water in the horizontal
pipes and water valve.
gasoline, pressurized containers, or any
other items or articles that are potential
fire hazards must NOT be placed on or
adjacent to the heater. The appliance
combustible materials, gasoline and
other flammable vapors and liquids.
Warning: The heater must be isolated
from the gas supply piping system
during any pressure testing of that
system at test pressures equal to or
more than 0.5 psig.
Warning: Place the heater in a location
where water leaks will do NO DAMAGE
to adjacent areas.
Heater placement and clearances
The GWH 425 PN is design certified for installation on
a combustible wall (see 3.4 Mounting installation)
provided the wall is not covered with carpet or other
fabric material. For installations in an alcove or closet,
maintain the minimum clearances to combustible and
non-combustible materials listed below. See also Fig. 4.
A. Top 12 inches (306 mm)
B. Front 4 inches (100 mm)
C. Back 0 inches
D. Sides 4 inches (100 mm)
E. Bottom 12 inches (306 mm)
6 720 608 034