Brochure

Flow curve
Index Point
0.1
10
0 . 01
0
. 1
0
. 02
0
. 03
0.02
0
.05
0
.2
0
.5
0 .0 5
1
0.2
0
. 3
0. 5
20 50
∆p (psi)
G (l/min) (
gpm
)
10
2
3
5
2 0
0
. 01
0
. 1
0
. 02
0
. 03
0 .0 5
1
0
. 2
0
. 3
0. 5
(psi) (bar)
10
2
3
5
2 0
1 0.1
0
.2
0.5 0.05 10 2 5 2
0
0 . 001
0
. 01
0
. 002
0
. 003
0 . 0 0 5
0 . 1
0
. 02
0
. 03
0
. 05
1
. 0
0
.2
0 . 3
0
. 5
4
0 .04
0.4
0 .04
0.4
4
0 . 0 04
0 . 0 4
0 .4
Cv = 3.0
Kv = 2.6
Use
Caleffi MIXCAL series 521 thermostatic mixing valves are designed to be
installed at the hot water heater. The Caleffi series 521 valve 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. They should not be used where ASSE 1070 devices are required.
Wherever a scald protection feature is required, Caleffi series 5213 high
performance 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 MIXCAL Series 521 thermostatic mixing valves should not be used
in conjunction with boilers giving instantaneous production of domestic hot
water. Their addition would compromise the correct operation of the boiler
itself.
Radiant panel heating systems
Caleffi MIXCAL Series 521 thermostatic mixing valves can also be used for
regulating the flow temperature in hydronic and radiant heating systems, to
which it assures a constant and accurate control with ease of installation.
Temperature
stability
The diagram shows
the stability of the
temperature of the
mixed water on
variation of the
temperature of the
stored water.
Installation
Before installing a Caleffi MIXCAL Series 521 three-way
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 Series 521 thermostatic mixing
valve is to be fitted must be drained and cleaned out to
remove any dirt or debris which may have accumulated
during installation.
The installation of filters of appropriate capacity at the inlet
of the water from the mains supply is always advisable.
Caleffi Series 521 thermostatic mixing valves must be
installed by qualified personnel in accordance with the
diagrams in this brochure, taking into account all current
applicable standards.
Caleffi Series 521 thermostatic mixing valves can be installed
in any position, either vertical or horizontal, or upside down.
The following are shown on the thermostatic mixing valve
body:
- Hot water inlet, color red and marked “HOT”.
- Cold water inlet, color blue and marked “COLD”.
- Mixed water outlet, marked “MIX”.
Check valves
In order to prevent undesirable backsiphonage, check
valves should be installed in systems with thermostatic
mixing valves. As a convenience for easier installations, the
Caleffi 521 "AC" series thermostatic mixing valves include
integral check valves in the hot and cold inlet ports.
Commissioning
In view of the special purpose of the thermostatic mixing valve,
it must be commissioned in accordance with current standards
by qualified personnel using temperature measuring
equipment. Caleffi 521519A and 521619A with integral outlet
port temperature gages provide a time-saving temperature
setting process to get close to the desired temperature. Use of
a digital thermometer is recommended for determing the final
setting of the mixed water temperature.
Temperature adjustment
The temperature is set to the required value by means of
the knob with the graduated scale, on the top of the valve.
M
I
N
M
A
X
7
1
2
3
Locking the setting
Position the handle to the
number required with
respect to the index point.
Unscrew the head screw,
pull off the handle and
reposition it so that the
handle fits into the internal
slot of the knob. Tighten
the head screw.
41
9 8 7 6 5 4 3 2 1 9 8 7 6 5 4 3 2 1
41 31 21 11 01 9 8 7 6 5 4 3 2 1
51 31 21 11 01
0
10
20
30
40
50
60
70
80
90
100
0
10
20
30
40
50
60
70
80
90
100
0
10
20
30
40
50
60
70
80
90
100
10
∞
C
2 min.
hot water
mixed water
cold water