North America • Latin America • India • Europe / Middle East / Africa • China • Pacific Rim
armstrong
international.com
Designs, materials, weights and performance ratings are approximate and subject to change without notice. Visit
armstrong
international.com for up-to-date information.
28
R
Re
effe
er
re
en
nc
ce
e d
diim
me
en
ns
siio
on
ns
s a
ar
re
e ±
± 1
10
0%
%
A
Allll d
diim
me
en
ns
siio
on
ns
s a
ar
re
e ±
± 1
1"
"
MM/DD/YY
MM/DD/YY
1/2"=1'
Custom
Dwg No.
Customer / Job name:
Scale:
Description:
Date:
Drawn/
Revised by:
Checked/
Apv. by:
Revision:
Description:
Date:
Drawn/
Revised by:
Checked/
Apv. by:
Revision:
(1)HWH 399 to 6x36 HSS
AJT
10/11/10
XX
To System
From
System
NOTE: The ABH cannot be drained of water without purging
the unit with air pressure, 15 PSIG (1barg) minimum. The
system’s air vent must be closed during this process.
Figure 5.1 - Boiler Piping
Table 5.1 Boiler Piping
Model
Boiler Only
GPM
∆
P (LPM)
Design
∆
T
Minimum Manifold Pipe Size
Single
Double
Triple
Quad
HW 299
11 @ 9.3'
(41.5 - 2.8)
51.8º F
28.8º C
1.5"
1.5"
2"
2"
HW 399
17.6 @ 8.5'
(66.6 - 3.5)
43.2º F
24.0º C
1.5"
2"
2"
2.5"
HW 599
26.4 @ 9.4'
(100-2.8)
45.3º F
25.2º C
1.5"
2"
2.5"
3"
NOTE: Flow rates shown above are for clean, closed loop systems.
Piping
Hydronic Heating Boiler Piping
ABH is designed to function in a closed loop (minimum) 12 PSIG (.8barg) System. Never let the ABH operate without a
minimum of 10 PSI water pressure, this assures that the ABH heat exchanger can be completely purged of air, failure to do
so could cause damage. It is important to note that the ABH Boiler is flow dependent for proper efficiency and life expectancy;
therefore, primary-secondary piping or use of a low loss header design is always recommended, as shown in the Figure
5.1 below. Each ABH Heating Boiler System should have an Air Eliminator, in addition to the heat exchanger mounted air
vent, which will remove air from the Hydronic System. Always follow good piping practices. Observe minimum 1" (25.4mm)
clearance to combustibles around all uninsulated hot water pipes, or when openings around pipes are not protected by non-
combustible materials. On an ABH installed above the level of the highest heat transfer device, some state and local codes
require a low water cut off device at the time of installation by the installer. A water flow switch is provided as standard and will
take the place of a low water cut-off. If the ABH supplies hot water to heating coils in air handler units, flow control valves or
other devices must be installed to prevent gravity circulation of boiler water in the coils during the cooling cycle.
Basic piping connection steps are listed below. A drawing, specific to your application can be obtained from your distributor or
Armstrong Hot Water, Inc., which will guide you through proper installation of the ABH.
1. Pipe properly, in accordance with generally accepted piping principals or Armstrong Hot Water, Inc. specific
documents.
2. Connect system return to the pipe entering the ABH closest to the back.
3. Connect system supply to the pipe leaving the ABH containing the Relief Valve.
4. Install Drain Valve on system supply.
