Introduction - American Water Heater 520 Installation Manual And Owner's Manual

INTRODUCTION

This manual provides information necessary for the installation, operation, and
maintenance of the 520 Indoor and Outdoor.
The model description is listed on the rating plate which is attached to the side panel of
the water heater.
Please read all installation instructions completely before installing this product.
If you have any problems or questions regarding this equipment, consult with the
manufacturer or its local representative.
The 520 Indoor and Outdoor are on-demand, tankless water heaters designed to
efficiently supply endless hot water for your needs.
The 520 Indoor and Outdoor are high efficiency models with an in-build secondary
heat exchanger that absorbs latent heat from the exhaust gas.
The principle behind the 520 Indoor and Outdoor Water Heater is simple:
Intake port
Primary heat
exchanger
Fan motor
Thermistor
PCB
1. A hot water tap is turned on.
2. Water enters the heater.
3. The water flow sensor detects the water flow.
4. The computer automatically ignites the burner.
5. Water circulates through the heat exchanger and then gets hot.
6. The computer will modulate the gas supply valve and water flow to produce the right
amount of hot water at the correct temperature.
7. When the tap is turned off, the unit shuts down.
Burner
Hot Water Outlet
3
Exhaust
Thermistor
Gas Valve
Condensate
Gas
drain port
Cold Water Outlet
│
Page
Introduction
Secondary heat exchanger
Bypass valve
Water control valve
Flow sensor
Thermistor
*This diagram
illustrates tankless
water heater design
concepts only and
does not accurately
represent to the 520
Indoor and Outdoor
physical description.