Bosch W 325 K**T1 Installation, Operation And Maintanance page 11

BOSCH INSTANTANEOUS WATER HEATERS APPROVED
When using the Bosch Models W 400-K for water heating and space heating the following requirements
shall apply :
All space heating equipment, piping and components connected to the heater shall be suitable for use
with potable water.
Toxic chemicals such as boiler treatment compounds, antifreeze etc, shall not be introduced into potable
water used for space heating.
When used for potable water this unit may not be connected to any heating system or components
previously used solely for space heating.
A temperature mixing valve must be installed where space heating temperature requirements are higher
than normal domestic supply temperatures to reduce scald hazard potential. Particular care must be
taken to select the correct type of thermal mixing valve to satisfy the installed application requirements,
i.e. If full anti-scald protection is specified then only that type of valve must be selected that is supported
by the manufacturer's claim. Below is a typical schematic which should be used as a guide only.
Always obey the installation instructions supplied by the mixing valve supplier.
Temperature Mixing
Valve Regulator
Feed to Space
Heating Equipment
Supply to
Bosch Heaters
Return from Bosch
Heaters and
Space Heating
FOR SPACE HEATING UNDER CLASS IV
130°F Hot
Water Service
check
valve
Cold Water Supply to
tempering regulator
HOT WATER
STORAGE
TANK
Note: These schematics and explanatory text should not be
used for design purposes, but only as a general guide. Actual
system design and installation must be by qualified people.
SEPARATE PUMPS REQUIRED
FOR HEATER AND CIRCULATION SYSTEM
Installations must conform to CSA B214 hydronic standard
and local code requirements.
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