American Water Heater Tankless Water Heater System - Manual (Page 22)

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-R
Domestic Hot W
ater - Circulation Systems
2 Tankless W
ater Heaters
Optional 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.
Ga
s
S
u
p
p
ly
L
in
e
Tankless
Wa
te
rH
ea
te
r
Pr
im
ar
y
Tankless
Wat
er
H
ea
te
r
Su
b
1
(Op
ti
o
n
a
l)
2-
10
G
a
ll
on
S
tor
age
T
ank
(T
o
e
li
m
inat
e
co
ld
w
a
te
r
s
a nd
w
ic
h
e
ec
t
caus
e
d
b
y
fr
e
q
u
e
n
t
O
n
/O
operat
ion)
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 Outlets
22
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. A
minimum of 3 GPM flow is recommended
for the circulation system. The pump should be sized to overcome the pressure loss through the Tankless water heater
, optional storage tank, 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 2 W
a
ter Heaters
Electronic Connection * * Refer to Tankless Accessories and Model
Applicability for
electronic connection details.