CALEFFI 5231 Series Guide

Low lead high-flow thermostatic mixing valves
NA10341.03
© Copyright 2018 Caleffi
ASSE 1017
Function
The thermostatic mixing valve is used in systems producing domestic
hot water or in radiant heating systems. Its function is to maintain the
temperature of the mixed water supplied to the user at a constant set
value when there are variations in the supply pressure and temperature
of the incoming hot and cold water or in the flow rate.
The 5231 series thermostatic mixing valves are ASSE 1017 approved for
point of distribution and are designed specifically for systems requiring
high flow rates and precise, stable temperature control. Optional
stainless steel inlet port check valves are available separately, for field
installation only.
Product range
5231 series thermostatic mixing valve. NPT male and sweat union
connections, sizes 1", 1-1/4", 1-1/2", 2". Inlet port check valve s and
outlet temperature gauge optional.
Technical characteristics
Materials: - body: DZR low-lead brass (<0.25% lead content)
- shutter: PPSG40
- springs: stainless steel
- seals: peroxide-cured EPDM
- check valve extension (field installed): stainless steel
www.caleffi.com
5231 Series
INSTALLATION AND COMMISSIONING MANUAL
Suitable fluids: water, glycol solutions
Max. percentage of glycol: 30% glycol solution
Mixed temperature adjustment range: 95 – 150°F (32 – 66°C)
Temperature stability: ± 3°F (± 2°C)
Max. operating differential pressure (static): 200 psi (14 bar)
Max. operating differential pressure (dynamic): 75 psi (5 bar)
Hot water inlet temperature range: 120 – 195°F (49 – 91°C)
Cold water inlet temperature range: 39 – 80°F (3.9 – 26.6°C)
Max. inlet pressure ratio (H/C or C/H) for optimum performance: 2:1
Min. temp. difference between hot inlet and mixed outlet for optimum perf: 20°F (11°C)
Max. water hardness: 10 grains
Certified to:
1. ASSE 1017/CSA B125.3, certified by ICC-ES, file PMG-1357.
2. NSF/ANSI 372-2011, Drinking Water System Components-Lead Content Reduction of
Lead in Drinking Water Act, California Health and Safety Code 116875 S.3874, Reduction
of Lead in Drinking Water Act, certifed by ICC-ES, file PMG-1360.
1

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.
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: If the thermostatic mixing 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 thermostatic mixing valve 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 can be dangerous. During
the installation, commissioning and maintenance of the thermostatic mixing
valve, take the necessary precautions to ensure that such temperatures do
not endanger people.
Leave this manual for the user.
CAUTION: To prevent any damage which will cause the electronic mixing
valve to not operate correctly, treat highly aggressive water before entering the
thermostatic mixing valve.
2

ATTENTION: Lorsque vous effectuez les raccordements d'eau, assurez-vous
que la tuyauterie reliant le termostatico regolabile n'est pas mécaniquement
des overstressed. Au fil du temps, ceci pourrait causer des ruptures, avec
pour consequence des pertes en eau qui, à leur tour, peuvent causer des
dommages à la propriété et/ou les gens.
Ce symbole d'avertissement servira dans ce manuel à attirer l'attention sur la sécurité concernant
instructions. Lorsqu'il est utilisé, ce symbole signifie.
ATTENTION! DEVENEZ ALERTE ! VOTRE SÉCURITÉ EST EN JEU ! NE PAS SUIVRE CES
INSTRUCTIONS PEUT PROVOQUER UN RISQUE DE SECURITE.
ATTENTION: Tous les travaux doivent être effectués par du personnel
qualifié formé à la bonne application, installation et maintenance des systèmes
conformément aux codes et règlements locaux.
ATTENTION:Si le réducteur de pression, termostatico regolabile, n'est pas installé,
mis en service et entretenu correctement, selon les instructions contenues dans ce
manuel, il peut ne pas fonctionner correctement et peut mettre en danger l'utilisateur.
ATTENTION: S'assurer que tous les raccordements sont étanches.
ATTENTION: Les températures de l'eau supérieure à 100°F (38°C) peut
être dangereux. Au cours de l'installation, mise en service et l'entretien de
le réducteur de pression, le termostatico regolabile, prendre les precautions
nécessaires afin de s'assurer que de tells températures ne compromettent
pas les gens.
ATTENTION: Pour prévenir tout dommage qui provoque le mitigeur
électronique à ne pas fonctionner correctement, le traitement de l’eau très
agressive avant d’entrer dans la vanne de le termostatico regolabile.
CONSIGNE DE SÉCURITÉ
LAISSEZ CE MANUEL AVEC L’UTILISATEUR
3

Operating principle
A thermostatic mixing valve mixes hot and cold water in such a way as to maintain a constant set
temperature of the mixed water at the outlet.
A thermostatic element is fully immersed into the mixed water. It then contracts or expands causing
movement of the piston, closing either the hot or cold inlets, regulating the flow rates entering the
valve. If there are variations of temperature or pressure at the inlets, the internal element automatically
reacts attempting to restore the original temperature setting.
The Caleffi 5231 series mixing valves require a minimum temperature differential from hot inlet
to mixed water outlet of 20°F (11°C) to ensure the correct operation, and maximum pressure
difference between the hot and cold inlet parts no greater than 2:1 ratio. Softened water use is highly
recommended as the warranty is voided if used on water with hardness greater than 10 grains.
Control
The Caleffi 5231 series
mixing valves require a
minimum temperature
differential from hot inlet to
mixed water outlet of 20°F
(11°C) to ensure the correct
operation, and maximum
pressure difference
between the hot and cold
inlet parts no greater than
2:1 ratio. Softened water
use is highly recommended
as the warranty is voided
if used on water with
hardness greater than 10
grains.
Check valves field installed only: code NA10366 for 1” & 1¼”
sizes; code NA10367 for 1½” & 2” sizes.
4
HOT
MIXED
COLD
HOT
MIXED
COLD
without inlet check valves
with inlet check valves (field installed)

Flow curves
.1
0.23
2.3
0.46
0.69
1.15
.3
1
∆p (ft of head)
G
(l/s)(gpm)
23
4.6
6.9
11.5
46
0.1
1
0.2
0.3
0.5
(psi) (bar)
10
2
3
5
20
10
2 5
20
0.01
0.1
0.02
0.03
0.05
1.0
0.2
0.3
0.5
9.2
0.92 0.4
4
0.04
0.4
50
100
1.5
3.25
1” 1 1/2” 2”
1 1/4”
∆p

50
160
6
10
2.0
5.0
115
172
75
Flow should never exceed standards for pipe size and material.
Size Connection Model
Min.
Flow*
(GPM)
Max.
Flow*
(GPM) CV
1" NPT 523160A 4.4 40 7
1" Sweat 523168A 4.4 40 7
1 ¼" NPT 523170A 4.4 40 7.6
1 ¼" Sweat w/
temp gauge
523177A 4.4 40 7.6
1¼" Sweat 523178A 4.4 40 7.6
1 ½" NPT 523180A 8.8 70 13
1 ½" Sweat 523188A 8.8 70 13
2" NPT 523190A 8.8 70 14.2
2" Sweat 523198A 8.8 70 14.2
*Recommended flow rates for temperature stabilty: ± 3°F (± 2°C).
5

Use
Caleffi 5231 series thermostatic mixing valves are designed to be installed at the hot water
heater and cannot be used for tempering water temperature at fixtures as a point-of-use
valve. They are not designed to provide scald protection or chill protection service and
should not be used where ASSE 1070 devices are required. Wherever a scald protection
feature is required, ASSE 1070 certified mixing valves need to be installed. For safety
reasons, it is advisable to limit the maximum mixed water temperature to 120°F.
Instantaneous production of hot water
Caleffi 5231 series thermostatic mixing valves are designed for use on domestic water heaters that
have storage. The valve may deliver fluctuating mixed temperatures when used on instantaneous
domestic water heaters.
Installation
Before installing a Caleffi 5231 series thermostatic mixing valve, the system must be inspected to
ensure that its operating conditions are within the range of the mixing valve, checking, for example,
the supply temperature, supply pressure, etc.
Systems where the Caleffi 5231 series thermostatic mixing valve is to be installed must
be drained and cleaned out to remove any dirt or debris which may have accumulated
during installation.
Failure to remove dirt or debris may affect performance and the manufacturer’s product
guarantee. Softened water use is highly recommended as the warranty is voided if used
on water with hardness greater than 10 grains.
The installation of filters of appropriate capacity at the inlet of the water from the mains
supply is always advisable.
In areas which are subject to highly aggressive water, arrangements must be made to
treat the water before it enters the valve.
Caleffi 5231 series thermostatic mixing valves must be installed in accordance with the diagrams
in this manual, taking into account all current applicable standards.
Caleffi 5231 series thermostatic mixing valves can be installed in any position, either vertical or
horizontal.
The following are shown on the mixing valve body:
- Hot water inlet, “H”.
- Cold water inlet, “C”.
- Mixed water outlet, unmarked.
In systems with thermostatic mixing valves, check valves must be installed to prevent undesirable
fluid backflow. The 5231 series valves, codes listed in this instruction sheet, do not contain integral
check valves, so those must be sourced separately. Caleffi offers inlet port check valve assemblies
separately, for field installation only to 5231 series valve.
It is essential that access to the valve is totally unobstructed for any maintenance which may be
required to the valve or connections. The piping from/to the valve must not be used to support the
weight of the valve itself.
6
·
Installation Tip
Scan to view
5231 MixCal
TM

7
Locking the setting
Position the knob at the required value,
unscrew the top screw, slide off the knob and
put it back in such a way that the handle fits
into the internal slot of the knob. Tighten the
head screw .
M
I
N
M
A
X
7
1
2
3
Index
Point
Dimensions
A
Sweat version
E
D
A
30
50
70
90
110 130
150
170
190
210
F
A
F
E
D
B B
C
A
A
HC
Code A B C D E F Wt (lb)
523160A 1" NPT 4" 8" 7 5/8" 4 3/16" 3 3/8" 7.0
523168A 1" SWT 3 5/16" 6 5/8" 7" 3 1/2" 3 3/8" 7.0
523170A 1 1/4" NPT 4 1/8" 8 1/4" 7 3/4" 4 5/16" 3 3/8" 7.0
523177A 1 1/4" SWT 3 3/8" 6 3/4" 7 5/8" 4 1/8" 3 3/8" 9.0
523178A 1 1/4" SWT 3 3/8" 6 3/4" 7" 3 1/2" 3 3/8" 7.0
523180A 1 1/2" NPT 5 1/8" 10 1/4" 9 3/16" 5 7/16" 3 3/4" 17
523188A 1 1/2" SWT 4 1/16" 8 1/8" 8 1/8" 4 3/8" 3 3/4" 17
523190A 2" NPT 5 1/8" 10 1/4" 9 1/2" 5 3/4" 3 3/4" 18
523198A 2" SWT 4 5/16" 8 5/8" 8 5/8" 4 7/8" 3 3/4" 18
Setting the temperature
The temperature is set to the required value
by means of the adjusting knob with the
graduated scale on the top of the valve.
Pos. Min 1234567Max
T (°F) 95 104 109 117 122 129 136 142 150
T (°C) 35 40 43 47 50 54 58 61 66
with: THOT = 155°F (68°C) · TCOLD = 55°F (13°C) · PINLETS = 43 psi (3 bar)

A
Sweat version
E
D
A
30
50
70
90
110 130
150
170
190
210
F
A
F
E
D
B B
C
A
A
HC
Code A B C D E F Wt (lb)
NA10366
1" NPT 5 1/2" 10 7/8" 7 5/8" 4 3/16" 3 3/8" 9.0
1" SWT 4 3/4" 9 1/2" 7" 3 1/2" 3 3/8" 9.0
1 1/4" NPT 5 5/8" 11 1/8" 7 3/4" 4 5/16" 3 3/8" 9.0
1 1/4" SWT 4 3/4" 9 5/8" 7 5/8" 4 1/8" 3 3/8" 11.0
1 1/4" SWT 4 3/4" 9 5/8" 7" 3 1/2" 3 3/8" 9.0
NA10367
1 1/2" NPT 7 3/8" 14 3/4" 9 3/16" 5 7/16" 3 3/4" 19
1 1/2" SWT 6 1/4" 12 5/8" 8 1/8" 4 3/8" 3 3/4" 19
2" NPT 7 3/8" 14 3/4" 9 1/2" 5 3/4" 3 3/4" 20
2" SWT 6 1/2" 13 1/8" 8 5/8" 4 7/8" 3 3/4" 20
Dimensions for 5231 models with field installed inlet check valve assembles, code
numbers listed in first column.
Dimensions with check valves
8

Replacement ttings
Code Description Tailpiece
all ports (3)
Inlet Check
Valve
Assembly (2)**
Outlet
adapter with
Temperature
Gauge**
Union
nuts (3)
Gaskets
(3)
523160A 1" MNPT union NA10009
NA10 366
NA10 476 R31589 R50057
523168A 1" Sweat union 31554 FD
523170A 1-1/4" MNPT union R416 60
523178A 1-1/4" Sweat union 41787 CST
523177A 1-1/4” Sweat union
with outlet temp. gauge*
41787 CST
(2 only)
R31589
(2 only
- 177A )
R50057
(2 only -
177A )
523180A 1-1/2” MNPT union 41371A
NA10 367 N A10461 R51838 R50060
523188A 1-1/2” Sweat union 41788 CST
523190A 2” MNPT union 41372A
523198A 2” Sweat union F0000496
*Replacement outlet mixed temperature gauge adapter complete with outlet tailpiece, union nut and gasket, and
temperature gauge (30-210°F), code NA10315.
**Field installed only
Replacement parts
Point of distribution mixed
temperature gauge adaptor fits
high flow 5231 series mixing
valves. Removable gauge fits into
temperature well.
Gauge dial is 2" diameter and
scale from 30—210º F.
Low-lead brass body.
Code Description Lbs
NA10315 1¼" sweat with gauge 0.5
NA10476 For 1” & 1 ¼” * 3.0
NA10476 For 1 ½” & 2” * 4.0
688003A Replacement gauge with pocket well 0.2
R39591 Replacement temperature gauge 0.2
Inlet check valve assembly for
mounting on inlet union tail pieces
of 5231 mixing valves. Stainless
steel body, acetal plastic check
valve insert with NBR o-ring.
Code Description Open Pressure Lbs
NA10366 Check valve assembly 1” & 1¼" 0.23 psi 1.0
NA10367 Check valve assembly 1½" & 2" 0.20 psi 1.5
Replacement body.
Meets requirements of
ANSI/NSF 372-2011.
Certified to: ICC-ES listed to
ASSE 1017/CSA B125.3,
Low lead.
ASSE 1017
5231
Code Description Min. Flow (gpm) Cv Lbs
523179A 1½" union thread 4.4 7.6 5.0
523199A 2½" union thread 8.8 14.2 15.0
Includes no fittings or union nuts.
* Requires separately ordered union nut, tailpiece and
union washer. See replacement fittings table above.
9

10
Commissioning
After installation, the valve must be tested and commissioned in accordance with the instructions
given below, taking into account current applicable standards.
1) Ensure that the system is clean and free from any dirt or debris before commissioning the
thermostatic mixing valve. Be sure water hardness is less than 10 grains.
2) It is recommended that the temperature is set using a suitable calibrated digital thermometer.
The valve must be commissioned by measuring the temperature of the mixed water at the outlet.
3) The maximum outlet temperature from the valve must be set taking account of the fluctuations
due to simultaneous use. It is essential for these conditions to be stabilized before commissioning.
4) Adjust the temperature using the adjusting knob on the valve. For safety reasons, it is advisable
to limit the maximum mixed water temperature to 120°F in domestic hot water systems.
Maintenance
Service tests should be carried out regularly to monitor the mixing valve performance, as deterioration
of performance could indicate that the valve and/or the system require maintenance. If, during
these tests, the temperature of the mixed water has changed significantly in comparison with the
previous test, the details given in the installation and commissioning sections should be checked
and maintenance carried out.
The following aspects should be checked regularly to ensure that the optimum performance levels
of the valve are maintained. Every 12 months at least, or more often if necessary.
1) Check and clean the system filters.
2) Check that any non-return valves positioned upstream of the Caleffi valve are operating correctly,
without problems caused by impurities.
3) Limescale can be removed from internal components by immersion in a suitable de-scaling
fluid.
4) When the components which can be maintained have been checked, commissioning should
be carried out again.

Application diagrams
T
Key to symbols
Safetyrelief valve
Check valve
Isolation valve
Expansion vessel
Filter
Pump
Domestic water system with recirculation connected to tank
MIN
M
A
X
7
1
2
Globe Valve
STORAGE
HOT WATER
HEATER
T
Key to symbols
Safetyrelief valve
Check valve
Isolation valve
Expansion vessel
Filter
Pump
Radiant panels heating system application
HOTCOLD
MIX
Radiant panel loop
MIN
M
A
X
7
1
2
Domestic water system with recirculation
ASSE 1017 model application
MIN
M
A
X
7
1
2
STORAGE
HOT WATER
HEATER
COLD
BLUE
HOT
RED
MIX
MIN M
A X
7
1
2
RETURN
SUPPLY
CALEFFI
CALEFFI
CALEFFI
CALEFFI
10
0
8
6
4
2
10
0
8
6
4
2
CALEFFI
CALEFFI
10
0
8
6
4
2
10
0
8
6
4
2
10
0
8
6
4
2
10
0
8
6
4
2
T
Key to symbols
Safetyrelief valve
Check valve
Isolation valve
Expansion vessel
Filter
Pump
Radiant panels heating system application
HOTCOLD
MIX
Radiant panel loop
MIN
M
A
X
7
1
2
Domestic water system with recirculation
ASSE 1017 model application
MIN
M
A
X
7
1
2
STORAGE
HOT WATER
HEATER
COLD
BLUE
HOT
RED
MIX
MIN M
A X
7
1
2
RETURN
SUPPLY
CALEFFI
CALEFFI
CALEFFI
CALEFFI
10
0
8
6
4
2
10
0
8
6
4
2
CALEFFI
CALEFFI
10
0
8
6
4
2
10
0
8
6
4
2
10
0
8
6
4
2
10
0
8
6
4
2
11
T
Key to symbols
Safetyrelief valve
Check valve
Isolation valve
Expansion vessel
Filter
Pump
Domestic water system without recirculation connected to tank
MIN
M
A
X
7
1
2
Globe Valve
STORAGE
HOT WATER
HEATER

Caleffi North America, Inc.
3883 West Milwaukee Road
Milwaukee, WI 53208
T: 414.238.2360 F: 414.238.2366
Troubleshooting
Under normal operating conditions the Caleffi 5231 series thermostatic mixing valve will provide a
very high level of performance. However, in some circumstances, where our maintenance plan is not
followed, the following problems may arise.
Symptom Cause Corrective action
Hot water at the cold taps a) Operation of check valve
is hindered; check valve is
not sealing correctly
b) Check valves not fitted
• Replace faulty check valves
Fluctuating mixer water
temperature
a) Erratic supply
temperatures at the inlets
of the valve
b) Starvation of the water
supplies at the inlets of
thevalve
c) Incorrect commissioning
ofthe valve
• Restore inlet conditions
within the limits of the valve
Erratic flow of water from
thevalve
a) Insufficient water supplies
b) Fluctuations in supply
pressures/temperatures
c) Adverse effect created by
other draw off points on
the system
• Stabilize inlet supply
conditions
No flow of water from
thevalve
a) In-line filters blocked
b) Insufficient supply
pressures
c) Debris obstructing
valveoperation
• Clean filters
• Restore inlet supplies
• Clean debris or scale
fromvalve
01-19-18
12