American Water Heater 318281-000 ユーザーズマニュアル

7

1

Solar collector 

Absorbs the sun’s heat energy and transfers this to the heat transfer 
fl uid circulating through the collector

2

Solar storage tank

Stores potable water heated by solar generated heat or installed 
back-up electric resistance element

3

Heat exchanger (Not Shown)

Transfers the heat from the collector loop to the potable water in the 
solar storage tank

4

Expansion tank

Allows for the expansion and contraction of the heat transfer fl uid as 
it heat and cools.

5

Temperature and Pressure relief 
valve

Required by plumbing code to automatically open and dump water if 
the storage tank exceeds 150 PSI of pressure or 210° F in tempera-
ture

6

Air vent

Purges air from the collector loop fl uid during the installation and is 
shut off later on to prevent glycol losses in steam phase.

7

Drain valve

Used to drain the heat transfer fl uid from the collector loop

8

Mixing valve

Used to temper hot water from the solar storage tank with cold inlet 
water to maintain appropriate temperature hot water delivered from 
the system

9

Solar pump station

Controls the fl ow of heat transfer fl uid from the collectors to the tank/
heat exchanger. For a detailed description of the solar pump station 
see page 20.

10

Temperature sensor

Tank and collector sensor work together to turn the circulating 
pump(s) on and off at preset temperature differentials

Never operate the electrical heating element without being 

certain the solar water heater is completely filled with water.  

If any air is left in the top of the tank, the heating element 
will burn out.
LOCAL CODES 

The installation of this  solar water heater must be in 

accordance with these instructions and all applicable local 

codes and electric utility requirements. In the absence of 

local codes, install in accordance with the latest edition of the 
National Electrical Code (NFPA-70).
TEMPERATURE-PRESSURE RELIEF VALVE 

For protection against excessive pressures and temperatures 

in this water heater, install temperature-pressure protective 

equipment required by local codes, but not less than a 

combination temperature-pressure relief valve certified by 

a nationally recognized testing laboratory that maintains 

periodic inspection of production of listed equipment or 

materials, as meeting the requirements for Relief Valves for 

Hot Water Supply Systems, the latest edition of ANSI Z21.22. 

This valve must be marked with a maximum set pressure not 

to exceed the marked hydrostatic working pressure of the 

water heater (150 lbs./sq. in.).
Install the temperature-pressure relief valve directly into the 

fitting of the water heater.  Position the valve downward and 

provide a discharge pipe that must terminate a maximum 

of six inches above a fl oor drain or external to the building. 

In cold climates, it is recommended that the discharge pipe 

be terminated at an adequate drain inside the building.  Be 

certain that no contact is made with any live electrical part. 

The discharge opening must not be blocked or reduced in size 
under any circumstances.  Excessive length, over 15 feet, or 
use of more than two elbows can cause restriction and reduce 
the discharge capacity of the valve.
No valve or other obstruction is to be placed between the 
temperature-pressure relief valve and the tank. Do not 
connect tubing directly to discharge drain unless a 6” air 
gap is provided. To prevent bodily injury, hazard to life 
or damage to property, the temperature-pressure relief 
valve must be allowed to discharge water in quantities 
should circumstances demand. If the discharge pipe is not 
connected to a drain or other suitable means, the water flow 
may cause property damage.
The Discharge Pipe:
•   Shall not be smaller in size than the outlet pipe size of the 

temperature-pressure relief valve, or have any reducing 
couplings or other restrictions.

•   Shall not be plugged or blocked.
•   Shall be of material listed for hot water distribution.
•   Shall be installed so as to allow complete drainage of both the 

temperature-pressure relief valve, and the discharge pipe.

•   Must terminate a maximum of six inches above a floor drain