A.O. Smith On Demand 305 Series 100 Design Manual page 32

Building Hot Water
Supply Line
Storage Tank
(No Burner or
Heating Element)
Submersible
Aquastat
(set @ 20°F below
On-Demand Temperature
Setting)
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.
On-Demand On-Demand
Water Heater Water Heater
Domestic Hot Water - Backup Storage
2 On-Demand Water Heater
Preferred Piping Installation
Check Valve
Pressure Relief Valve
Set water heaters @ 20°F
above storage tank Aquastat
Pump / Aquastat Control Wire
Pressure Regulator
S
Circulating Pump
.
The Contractor or
32
On-Demand
Equipment List
On-Demand Commercial
Water Heaters
Gas Supply
Reference the section
on Pump Sizing for
Storage Tank Application.
Cold Water Supply Line
Expansion Tank
Boiler Drain Valve
Solenoid Valve Mixing Valve
Drawing Date:
September 07, 2008
Drawing Number:
H-2-T
QTY
2