American Water Heater Tankless Water Heater System - Manual (Page 21)

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-2-RGE
Domestic Hot W
ater - C
ir
cu
la
ti
o
n
S
ys
te
m
s
2 Tankless W
ater Heaters with Gas or Electric Tank
Preferred Piping Inst
allation
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.
Expansion T
ank
M
inimum 3/4
“ C
old
W
a
ter Supply Line
M
inimum 3/4
“ Hot
W
a
ter Supply Line
Building Supply
Ga
s
S
u
p
p
ly
L
in
e
Tankless
Wa
te
rH
ea
te
r
Pr
im
ar
y
Tankless
W
ate
rH
ea
te
r
Su
b
1
G
as or Elec
tric
Tank W
a
ter
Heater
21
Impor
tant:
Install r
eturn line to the hot
supply line as close as possible to the R
innai water heater
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.
Tankless Equipment List
QTY
Tankless 2 W
a
ter Heaters
Electronic Connection *
* Refer to Tankless Accessories and Model
Applicability for
electronic connection details.