CALEFFI DISCAL NA551 Series User guide

Function
The DISCAL
®
air separator is used to continuously remove the air
contained in the hydronic circuits of heating and cooling systems.
The air discharge capacity of these devices is very high. They are
capable of removing automatically all the air present in the system
down to micro-bubble level.
The circulation of fully de-aerated water enables the equipment to
operate under optimum conditions, free from any noise, corrosion,
localized overheating or mechanical damage. Micro-bubbles, fusing
with each other, increase in volume (get larger) until they become
large enough to rise to the top where they are automatically
released.
This item is designed for use in closed hydronic systems. Do not use this item in plumbing applications. It does
not meet the low-lead plumbing standards of U.S. and Canada.
Product range
551 series DISCAL air separator for horizontal pipes, in brass compact with drain
Sizes ¾” integral sweat; ¾” NPT female (A without service check valve, AC with
service check)
551 series DISCAL air separator for horizontal pipes, in brass with drain
Sizes ¾” - 1” - 1 ¼” - 1 ½” - 2” NPT female; 1” - 1 ¼” - 1 ½” - 2” integral sweat
(A without service check valve, AC with service check)
551 series DISCAL air separator for horizontal pipes, in brass with drain
Sizes 1” - 1 ¼” - 1 ½” - 2” press (A without service check valve, AC with service check)
5517 series DISCAL air separator for horizontal or vertical pipes with rotating collar, in brass with
drain. Sizes ¾” and 1” sweat union, press union and NPT male union
551 series DISCAL air separator for horizontal pipes, in steel with flanged connections with drain
Sizes 2” – 6” ANSI
NA551 series DISCAL air separator for horizontal pipes, in steel with flanged
connections with drain designed and built in accordance with Section
VIII, Division 1 of the ASME Boiler and Pressure Vessel Code and
tagged and registered with the National Board of Boiler and Pressure
Vessel Inspector, with ASME U-stamp. Sizes 2” – 12” ANSI.
Installation, commissioning and servicing instructions
38456.11
www.caleffi.com
1
551- 5517 - NA551 Series
© Copyright 2018 Caleffi
DISCAL®air separator
·
Installation Tip
Scan to view
NA551 & 551 DISCAL®

2
Technical specications
Brass air separator
Materials - body: brass
- internal element
(compact and rotating collar versions): 304 stainless steel
- internal element: glass reinforced nylon PA66GF30
- seal: peroxide-cured EPDM
- air vent float: PP
- air vent float linkages: stainless steel
- air vent float guide pin: stainless steel
Performance
Suitable fluids: water, glycol solution
Max. percentage of glycol: 50%
Max. working pressure: 150 psi (10 bar)
Temperature range: 32–250°F (0–120°C)
Air separation efficiency: 100% to micro-bubble level
Connections - main:
compact series: 3/4" sweat; 3/4" NPT female
horizontal: 3/4", 1", 1-1/4", 1-1/2" and 2" NPT female
1", 1-1/4", 1-1/2 " and 2"integral sweat
1” , 1-1/4”,1-1/2” and 2” integral press
rotating collar version, 5517 series: ¾” and 1” sweat, press and NPT male union
- lay length (press connection): see page 4 and 5
- drain: 1/2" NPT female
5517 series: 1/2” straight female
Steel air separator
Materials - body: epoxy resin painted steel
- internal element: 304 stainless steel
- seal: peroxide-cured EPDM
- air vent float: PP
- air vent float linkages: stainless steel
- air vent float guide pin: stainless steel
Performance
Suitable fluids: water, glycol solution
Max. percentage of glycol: 50%
Max. working pressure: sizes 2-6”: 150 psi (10 bar); sizes 8-12”: 200 psi (14 bar)
Temperature range: 32–270°F (0–132°C)
Air separation efficiency: 100% to micro-bubble level
Connections - flanged: 2"– 12" ANSI B16.5 150 CLASS RF
- drain pipe: sizes 2 - 6 inch: 1" NPT male
sizes 8 - 12 inch: 2” NPT male
Agency Approval
NA551 series is designed and built in accordance with Section VIII, Division 1 of the ASME Boiler
and Pressure Vessel Code and tagged and registered with the National Board of Boiler and
Pressure Vessel Inspector, and CRN registered (12” pending, contact Caleffi).

CAUTION: If the DISCAL valve is not installed, commissioned and
maintained properly, according to the instructions contained in this
manual, it may not operate correctly and may endanger the user.
CAUTION: Make sure that all the connecting pipework is water tight.
CAUTION: When making the water connections, make sure that the
pipework connecting the DISCAL is not mechanically over-stressed. Over
time this could cause breakages, with consequent water losses which, in turn,
could cause harm to property and/or people.
CAUTION: Water temperatures higher than 100°F (38°C) can be dangerous.
During the installation, commissioning and maintenance of the DISCAL valve,
take the necessary precautions to ensure that such temperatures do not
endanger people.
Leave this manual for the user
SAFETY INSTRUCTION
This safety alert symbol will be used in this manual to draw attention to safety related
instructions. When used, the safety alert symbol means.
ATTENTION! BECOME ALERT! YOUR SAFETY IS INVOLVED! FAILURE TO
FOLLOW THESE INSTRUCTIONS MAY RESULT IN A SAFETY HAZARD.
CAUTION: All work must be performed by qualified personnel trained in the
proper application, installation, and maintenance of systems in accordance
with all applicable codes and ordinances.
FLOW-CONTROL
STYLE
TYPE OF
SOLDER
MAXIMUM LIMITATIONS
PRESSURE PSI TEMPERATURE °F
SWEAT
95-5
Tin-Antimony 150 250
50-50 tin-Lead 125 150
60-40 tin-Lead 75 250
Working Pressure & Temperature Limits
(Solder Type Limits Per ASTM Std. B16.18-1979)
3
WARNING: This product can expose you to chemicals including lead, which is known
to the State of California to cause cancer and birth defects or other reproductive harm.
For more information go to www.P65Warnings.ca.gov.

D
B
E
A A
A
D
B
E
A
A
D
B
E
A
F
G
F
B
AD
E
F F
A
D
B
E
F
A
G
F
B
AD
E
Tmax250F
Pmax150 psi
Tmax220F
Pmax150 psi
BI-DIRECTIONAL
38466.01
Tmax250F
Pmax150 psi
Tmax220F
Pmax150 psi
BI-DIRECTIONAL
38466.01
A
A
D
E
C
C
C
C C
C C
B
G
A
D
B
E
A
F
C
*Add suffix C to sweat and NPT code number when ordering the brass
DISCALto ship with expansion tank service check valve, code561402A.
1/2 ”
E
C
B
F
D
Code A B C D E F Wt (lb)
551705A 3⁄4" NPT 51⁄8" 23⁄16" 53⁄8" 91⁄4" 31⁄2" 4.9
551765A 3⁄4" press 63⁄8" 23⁄16" 53⁄8" 93⁄4” 31⁄2" 4.9
551795A 3⁄4" SWT 6" 23⁄16" 53⁄8" 93⁄16” 31⁄2" 4.9
551706A 1" NPT 63⁄4" 23⁄16" 53⁄8" 93⁄4” 31⁄2" 4.9
551766A 1" press 63⁄4" 23⁄16" 53⁄8" 93⁄4” 31⁄2" 4.9
551796A 1" SWT 7" 23⁄16" 53⁄8" 93⁄4” 31⁄2" 4.9
551716* -- 33⁄4” 23⁄16" 53⁄8" 91⁄4" 31⁄2" 4.4
*Body only, no end connection fittings. Source separately, see Caleffi
catalog for end connection code numbers.
Code A Lay length
551765A 3⁄4" press 4 5⁄8"
551766A 1" press 4 3⁄4"
Dimensions
Code A B C D E F Wt (lb)
551003A* 3⁄4" NPT 31⁄16" 23⁄16" 53⁄8" 67⁄8"1⁄2" 2.0
551022A* 3⁄4" SWT 31⁄16" 23⁄16" 53⁄8" 67⁄8"1⁄2" 2.0
4

D
B
E
A A
A
D
B
E
A
A
D
B
E
A
F
G
F
B
AD
E
F F
A
D
B
E
F
A
G
F
B
AD
E
Tmax250F
Pmax150 psi
Tmax220F
Pmax150psi
BI-DIRECTIONAL
38466.01
Tmax250F
Pmax150 psi
Tmax220F
Pmax150 psi
BI-DIRECTIONAL
38466.01
A
A
D
E
C
C
C
C C
C C
B
G
A
D
B
E
A
F
C
*Add suffix C to sweat, NPT and press (below) code numbers when
ordering the brass DISCAL to ship with expansion tank service check
valve, code561402A.
D
B
E
A A
A
D
B
E
A
A
D
B
E
A
F
G
F
B
AD
E
F F
A
D
B
E
F
A
G
F
B
AD
E
Tmax250F
Pmax150 psi
Tmax220F
Pmax150psi
BI-DIRECTIONAL
38466.01
Tmax250F
Pmax150 psi
Tmax220F
Pmax150 psi
BI-DIRECTIONAL
38466.01
A
A
D
E
C
C
C
C C
C C
B
G
A
D
B
E
A
F
C
Code A B C D E F Wt (lb)
551005A* 3⁄4" NPT 45⁄16" 23⁄16" 53⁄4" 71⁄2"1⁄2" 3.7
551006A* 1" NPT 45⁄16" 23⁄16" 53⁄4" 71⁄2"1⁄2" 3.7
551007A* 11⁄4" NPT 47⁄8" 23⁄16" 69⁄16" 81⁄4"1⁄2" 4.9
551008A* 11⁄2" NPT 47⁄8" 23⁄16" 69⁄16" 81⁄4"1⁄2" 4.9
551009A* 2" NPT 51⁄8" 23⁄16" 69⁄16" 81⁄4"1⁄2" 5.5
551028A* 1" SWT 51⁄16" 23⁄16" 53⁄4" 71⁄2"1⁄2" 3.7
551035A* 11⁄4" SWT 53⁄16" 23⁄16" 65⁄16" 81⁄4"1⁄2" 3.7
551041A* 11⁄2" SWT 53⁄4" 23⁄16" 69⁄16" 81⁄4"1⁄2" 4.9
551054A* 2" SWT 61⁄8" 23⁄16" 69⁄16" 81⁄4"1⁄2" 5.5
Code A B C D E F Wt (lb)
551066A* 1" press 6 3⁄16"23⁄16" 53⁄4" 71⁄2"1⁄2" 3.8
551067A* 1¼" press 7 7⁄16" 23⁄16" 53⁄4" 71⁄2"1⁄2" 5.0
551068A* 11⁄2" press 8"23⁄16" 69⁄16" 81⁄4"1⁄2" 5.1
551069A* 2" press 81⁄2" 23⁄16" 69⁄16" 81⁄4"1⁄2" 5.5
Code A Lay length
551066A* 1" press 4 1⁄2"
551067A* 1¼" press 5 1⁄8"
551068A* 11⁄2" press 5 1⁄4"
551069A* 2" press 5 1⁄2"
5

D
B
E
A A
A
D
B
E
A
A
D
B
E
A
F
F J
C
B
A
H
D
E
F F
A
D
B
E
F
A
F
Tmax250ϒF
Pmax150 psi
Tmax220ϒF
Pmax150 psi
BI-DIRECTIONAL
38466.01
A
A
D
E
C C C
C C
G
B
G
WALL
**Add prefix NA to flanged code number when ordering ASME tagged and registered with the
National Board of boiler and Pressure Vessel Inspector and CRN registered.
†This dimension allows for a minimum of 3" wall clearance to accommodate insulation if used.
Code A B C D E F G H J†Wt (lb)
**551050A 2" 133⁄4" 1" 143⁄4" 1915⁄16" 65⁄8" 213⁄16" 6" 65⁄16" 34
**551060A 21⁄2" 133⁄4" 1" 143⁄4" 1915⁄16" 65⁄8" 213⁄16" 7" 65⁄16" 35
**551080A 3" 183⁄8" 1" 171⁄8" 237⁄16" 85⁄8" 213⁄16" 71⁄2" 75⁄16" 62
**551100A 4" 181⁄2" 1" 171⁄8" 237⁄16" 85⁄8" 213⁄16" 9" 75⁄16" 67
NA551120A 5" 25" 1" 217⁄16" 301⁄2" 123⁄4" 213⁄16"10" 93⁄8" 106
NA551150A 6" 25" 1" 217⁄16" 301⁄2" 123⁄4" 213⁄16"10" 93⁄8" 117
Size 2" 2 1⁄2" 3" 4" 5" 6"
Cap. (gal) 1.8 1.8 4.8 4.8 13.7 13.7
Dimensions
6

G
A
F
E
2”
2-13/16”
D
38783
Tmax 110C
Pmax 10 bar
BI-DIRECTIONAL
B
Code A B D E F G
Cap.
(gal)
Wt
(lb)
NA551200A 8" 35 7/16" 20" 8 1/2" 20" 32 1/2" 56 335
NA551250A 10" 41 3/4" 26" 8 1/2" 22 5/8" 38 1/4" 110 617
NA551300A 12" 46 1/2" 30" 8 1/2" 25 3/8" 43 3/8" 169 871
These models are ASME tagged and registered with the National
Board of Boiler and Pressure Vessel Inspector and CRN registered (12"
pending, consult Caleffi).
NOTE: Drawings may not reflect the actual size of the separators.
7

Hydraulic characteristics
8
0.56
G
(l/s) (gpm
)
(kPa)
2.8
1.4
0.33 0.39 0.44 0.50
0.69
0.83 0.97
1.1
1.25
1.7 1.9 2.2 2.5 3.3 3.9 4.4 5.0 6.9
11 12
5.6
8.3 9.7
14
2”
2 1/2”
28
17 19 22 25
3” 4”
33 39 44 50
56
5” 6”
0. 1
0. 05
0.09
0.08
0.07
0.06
0.035
0.04
0.045
0.12
0.14
0.16
0.18
0.25
0.3
0.35
0. 2
1
0
. 1
0
. 2
0
. 5
0.9
0.8
0.7
0.6
0.12
0.14
0.16
0.18
0.25
0.3
0.35
0.4
0.45
1.2
1.4
1.6
1.8
2.5
3
2
1
0. 5
0.9
0.8
0.7
0.6
0.45
0.4
0.09
0.08
0.07
0.06
0.025
0.03
0. 0 2
( ft of water ) Δ P ( ft of water )
100
10
5
20 50
1000
200
500
0. 1
0. 05
0.09
0.08
0.07
0.06
0.035
0.04
0.045
0.12
0.14
0.16
0.18
0.25
0.3
0.35
0. 2
1
0. 5
0.9
0.8
0.7
0.6
0.45
0.4
0.025
0.03
0. 0 2
6 7 8 9
12 14 16 18
25 30 35
40 45 60 70 80 90
120 140 160 180 250 400 450
300
350 600 700 800 900
1.2
1.4
1.6
1.8
2
6
4.5
1.2
1.4
1.6
1.8
2
69 83 97
111 125
2000
1200 1400
1600 1800
4
3.5
5
12” 10”
8”
4.3 4.0
3.5 3.0 2.7
2.2
0.27
0.25 0.22 0.19 0.17
0.14
1” 3/4” C
1 1/4”
3/4”
3/4" - 1" Rotatting Collar
2” Steel
ft of water x .433 = psi
R: 5517 series rotating collar version.
C: Compact version.
Flow capacity — brass
Size ¾"
C/R ¾" 1" R 1" 1¼" 1½" 2"
4.0 f/s GPM 6 6 10 10 15 22 39
l/s 0.4 0.4 0.6 0.6 1.0 1.4 2.5
Cv 12/14 19 14 32 56 73 81
Flow capacity — steel
Size 2" 2 ½" 3" 4" 5" 6" 8" 10" 12"
4.0 f/s GPM 39 60 90 160 245 355 625 980 1,410
l/s 2.5 3.8 5.7 10 15.5 22.4 40.0 62.0 89.0
10.0 f/s GPM 100 155 220 400 615 880 1,570 2,450 3,530
l/s 6.3 9.8 14 25.2 38.8 55.5 99.0 154.5 222.7
Cv 87 174 208 324 520 832 1,109 1,387 1,664

9
Installation
DISCAL units may be used in heating or cooling systems to ensure the progressive removal of
air which is continuously formed. The units should preferably be installed after the boiler and on
the pump suction side, as these are the points where the formation of micro-bubbles is greatest.
DISCAL air separators for horizontal pipes must be installed vertically. Flow direction of the DISCAL
air separator is bidirectional (flow in either direction is permitted), except for the 5517 series rotating
collar version. For the 5517 series, the correct flow direction is shown by an arrow on the T-fitting.
Turn the T-fitting by hand to correctly orient it to install in either horizontal or vertical piping. In
installation conditions where inspection is not possible, it is recommended that the venting valve
cap is replaced by a Caleffi Code R59681 hygroscopic safety vent. The standard replacement cap
code is 59119.
Tmax250F
Pmax150psi
Tmax220F
Pmax150psi
BI-DIRECTIONAL
38466.01
Tmax250F
Pmax150psi
Tmax220F
Pmax150psi
BI-DIRECTIONAL
38466.01
Tmax250F
Pmax150psi
Tmax220F
Pmax150psi
BI-DIRECTIONAL
38466.01
Tmax250F
Pmax150psi
Tmax220F
Pmax150psi
BI-DIRECTIONAL
38466.01
Tmax250F
Pmax150psi
Tmax220F
Pmax150psi
BI-DIRECTIONAL
38466.01
Tmax250F
Pmax150psi
Tmax220F
Pmax150psi
BI-DIRECTIONAL
38466.01
Tmax250F
Pmax150psi
Tmax220F
Pmax150psi
BI-DIRECTIONAL
38466.01
Tmax250F
Pmax150psi
Tmax220F
Pmax150psi
BI-DIRECTIONAL
38466.01
Tmax250F
Pmax150psi
Tmax220F
Pmax150psi
BI-DIRECTIONAL
38466.01
Tmax250F
Pmax150psi
Tmax220F
Pmax150psi
BI-DIRECTIONAL
38466.01
Tmax250F
Pmax150psi
Tmax220F
Pmax150psi
BI-DIRECTIONAL
38466.01
Tmax250F
Pmax150psi
Tmax220F
Pmax150psi
BI-DIRECTIONAL
38466.01
Tmax250F
Pmax150psi
Tmax220F
Pmax150psi
BI-DIRECTIONAL
38466.01
Tmax250F
Pmax150psi
Tmax220F
Pmax150psi
BI-DIRECTIONAL
38466.01
Tmax250F
Pmax150psi
Tmax220F
Pmax150psi
BI-DIRECTIONAL
38466.01
Tmax250F
Pmax150psi
Tmax220F
Pmax150psi
BI-DIRECTIONAL
38466.01
CHILLER

Construction details
DISCAL air separators are designed to allow
maintenance and cleaning without having to
remove the valve body from the piping. All
DISCAL air separators come standard with a
bottom connection for installing a drain valve.
All internal air release control components are
fully accessible in all the models.
The automatic air vent, located at the top
of the units, has a long chamber for the
movement of the
float. This feature
prevents any
debris present in
the water from
reaching the
sealing seat. A
stainless steel
float guide pin (3)
prevents the float
from sticking due
to accumulating
residue in the
flowing fluids,
4
3
6
5
5
3
4
4
4
3
6
5
5
3
4
4
59829
even when the DISCAL air separator is not
installed perfectly vertical.
A replacement air vent assembly for the
DISCAL brass 551 series (except rotating
collar and compact versions) is code 59829;
for the DISCAL steel 551 and NA551 series is
code 59756.The moving parts that control air
venting are accessed simply by removing the
upper cover (4). Replacement cap and float
assembly for all versions of the brass DISCAL
551 and 5517series is code F39807.
When cleaning, simply unscrew the portion
of the body containing the
automatic air vent (5). For the
rotating collar and compact
models, the element can be
removed by removing the
upper cover(4). There is no
need to remove the air vent
body for these models.
4
3
6
5
5
3
4
4
F39807
59756
10

4
3
6
5
5
3
4
4
4
3
6
5
5
3
4
4
4
11

Caleffi North America, Inc.
3883 West Milwaukee Road
Milwaukee, WI 53208
T: 414.238.2360 F: 414.238.2366
Accessories
Item Code Description
561402A Check valve for expansion tanks.
1/2" NPT connections.
R59681 Hydroscopic safety vent cap.
562100 Small anti-vacuum vent cap.
5 9119 Replacement DISCAL air ventcap.
10-12-18
12
Insulation shells for brass DISCAL series for
horizontal pipes. These are not designed for the
compact or 517 series rotating collar DISCAL.
Code Size
CBN551005 For ¾" and 1"
CBN551007 For 1¼" and 1½"
CBN551009 For 2"
Optional drain valves, separator sizes 2" - 6", code NA39753 (1" NPT female with T handle);
separator sizes 8" -12", code NA59600 (2" NPT female with lever).