General rules to follow for safe
B 1. You should follow these instructions when you
install your water heater. In the United States: The
installation must conform with local codes or, in the
absence of local codes, the National Fuel Gas Code
ANSI Z223.1/NFPA 54.
In Canada: The Installation should conform with
CGA B149.(1,2) INSTALLATION CODES and /or
local installation codes.
B 2. Carefully plan where you install the water heater.
Correct combustion air supply and vent pipe
installation are very important. If not installed
correctly, fatal accidents can be caused by lack of air,
carbon monoxide poisoning or fire.
B 3. The National Fire Codes do not allow
UNSEALED gas fired water heater installations
in bathrooms, bedrooms or any occupied
rooms normally kept closed. See chapter 3.2
B 4. You must vent your water heater. See section on
B 5. The appliance and its gas connection must be leak
tested before placing the appliance in operation.
The appliance must be isolated from the gas supply
piping system by closing its individual manual gas
shutoff valve (not supplied with water heater) during
any pressure testing at pressures in excess of ½ Psig
B 6. Keep water heater area clear and free from
combustibles and flammable liquids. Do not locate
the heater over any material which might burn.
B 7. Correct gas pressure is critical for the optimum
operation of this water heater. Gas piping must be
sized to provide the required pressure at the
maximum output of the water heater, while all the
other gas appliances are in operation. Check with
your local gas supplier, and see the section on
connecting the gas supply.
B 8. Should overheating occur or the gas supply fail to
shut off, turn off the gas supply at the manual gas
shut off valve, on the gas line. Note: manual gas
shutoff valve is not supplied with the water heater.
B 9. Do not use this appliance if any part has been
underwater. 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 underwater.
GWH-450-ES always work as master.
Cascading enables the appliance to be connected in
parallel with up to 4 World 1 appliances. World 1 will
only start, if it gets a signal from the GWH-450-ES and
will (at a defined power output level) give this signal to
the next appliance. That means, the appliance works
always as a Master to the next appliance and always as
a Slave to the one before.
For more detailed information about this feature, consult
the instructions supplied with the accessorie:
• 7 709 003 617.
6 720 607 915