A.O. Smith On Demand 305 Series 100 Design Manual page 31

Building Hot Water
(set @
Demand Temperature
Key
3/4" Ball Valve
3/4" Union
NOTE: This drawing is not intended to describe a complete system and is not a replacement for a pro-
fessional engineering drawing. It is intended only as a guide and does not imply compliance with local
building code requirements. Confer with local building officials before installation
engineer is to determine the necessary components and configuration of the particular system to be in-
stalled. It is the responsibility of the engineer or contractor to ensure that the installation is in accordance
with all local building codes.
Supply Line
Storage Tank
(No Burner or
Heating Element)
Submersible
Aquastat
20°F below On-
Setting)
Pump / Aquastat Control Wire
Building
Circulation
Building Hot Water
Pump
Return Line
Domestic Hot Water - Backup Storage / Circulation
1 On-Demand Water Heater
Preferred Piping Installation
Check Valve
Pressure Relief Valve
Set @ 20°F above
On-Demand
Water Heater
storage tank Aquastat
Reference the section on
Pump Sizing for Storage Tank
Application.
Expansion Tank
Pressure Regulator
S
Circulating Pump
. The Contractor or
31
On-Demand
Equipment List
On-Demand
Water Heater
Gas Supply
Cold Water Supply Line
Boiler Drain Valve
Solenoid Valve Mixing Valve
Drawing Date:
September 07, 2008
Drawing Number:
H-1-TC
QTY
1