American Water Heater Tankless Water Heater System - Manual (Page 23)

23
Domestic Hot Water - Circulation Systems
3 Tankless Water Heaters with Gas or Electric Tank
Preferred Piping Installation
Tankless
Water Heater
Tankless
Water Heater
Drawing Number: Drawing Date:
Pres
s
ure R
e
lief
Valv
e
3/
4"
Ball
Valv
e
3/
4"
U
n
ion
C
h
ec
k Valv
e
Ke
y
S
Pres
s
ure R
egulat
or
C
irc
ulat
ing Pum
p
Solenoid Valv
e
Boiler D
rain Valv
e
WH-3-RGE February 27, 2008
This is not an engineering drawing; it is intended only as a guide and not as a replacement for professional engineering project drawings.
This
drawing is not intended to describe a complete system. It is up to the contractor or engineer to determine the necessary components and configuration of the particular system to be installed.
The drawing does
not imply compliance with local building code requirements. It is the responsibility of the engineer or contractor to ensure that the installation is in accordance with all local building codes. Confer with local building of
ficials before installation.
Gas Supply
Tankless
Water Heater
Primary
Su
b 1
C
o
ld
W
a
te
r
S
u
p
p
ly
L
in
e
Hot
Water Supply Line
Smaller Return Line Can Be Used After The Last Fixture
Expansion Tank
Su
b 2
(Optional) Header Sized One Pipe
Size Larger Than Hot
Water Supply Line - (
To e
liminate c
old
water
sa
ndwic
h effec
t
cau
s
ed b
y
frequ
ent
On/Off op
eration)
Gas or Electric
Tank Water
Heater
Tank Water Heater sized to maintain circulation loop temperature
Building Outlets
For this application: Pump should be controlled by an
Aquastat,
T
imer or Combination
Aquastat and
T
imer
.
Pump to be sized to maintain circulation loop temperature. The pump should be sized to overcome the pressure loss through the tank water heater
,
and supply and return plumbing in the circulation loop. Reference the section Pump Sizing for Circulation
.
Pump to be of bronze or stainless construc- tion.
A
quastat C
onnec
tion
Tankless Equipment List
QTY
Tankless 3 W
a
ter Heaters
Electronic Connection * * Refer to Tankless Accessories and Model
Applicability for
electronic connection details.