Drawing Number:
Drawing Date:
H-3-TC
September 07, 2008
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. The Contractor or
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.
35
On-Demand
Equipment List QTY
On-Demand 3
Water Heaters
Domestic Hot Water - Backup Storage / Circulation
3 On-Demand Water Heaters
Preferred Piping Installation
On-Demand
Water Heater
On-Demand
Water Heater
On-Demand
Water Heater
Set water heaters @20°F
above storage tank Aquastat
Storage Tank
(No Burner or
Heating Element)
Submersible
Aquastat
(set @ 20°F below On -
Demand Temperature
Setting)
Reference the section on
Pump Sizing for Storage Tank
Application.
Building
Circulation
Pump
Pump / Aquastat Control Wire
Cold Water
Supply Line
Building Hot Water
Supply Line
Gas Supply
Expansion Tank
Building Hot Water
Return Line
Key
Pressure Relief Valve
Check Valve
3/4" Union
3/4" Ball Valve
Boiler Drain Valve
Solenoid Valve
S
Pressure Regulator
Circulating Pump
Mixing Valve