CALEFFI Uni-Switch 626 Series User manual

Function
The Caleffi Series 626 water flow switch detects the presence
or absence of flow in piping of heating, air conditioning, cooling
and water treatment systems as well as in pumping and process
systems. In heating systems, the flow switch is normally used to
shut off the burner of the boiler whenever there is no circulation
of the carrier fluid in the boiler circuit. A lack of circulation
can damage critical components and impair the operation of
temperature sensitive safety and protection devices.
This item is designed for use in closed hydronic systems. Do not
use in plumbing applications. This item does not meet the low-lead
plumbing standards of U.S. and Canada.
General Characteristics
A stainless steel bellows separates the electrical and hydronic sections, preventing the possibility
of contact of the fluid with the electrical components. Stainless steel is used in the construction
of many key parts, including the bellows, which protects the switch from corrosion. With a protection
classification of NEMA type 3 (IP54), the switch can be used in particularly humid and dusty
environments. The cover is made of a special non-combustible plastic material. The normally open
and normally closed contacts on the switch enable any electrical device to be switched on or off
as required at the operating flow rate. The operating point can be easily adjusted with the calibration screw.
Technical Characteristics
Connection size:
Maximum operating pressure:
Maximum temperature of the fluid:
Minimum temperature of the fluid:
Maximum ambient temperature:
Suitable for pipes:
Electrical Data
Max. Voltage:
Max. Current:
Electrical connection:
Protection class:
Certification Mark:
1” NPT male
150 psig (10 bar)
250° F (120° C)
-20° F (-30° C)
130° F (55° C)
1” to 8” (25 to 200mm)
250 VAC
15A
½” NPT threaded with strain relief
NEMA type 3 (IP54)
Uni-Switch™ Universal Flow Switch
© Copyright 2022 Caleffi
68235.07
www.caleffi.com
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626 Series

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.
CAUTION: Over-tightening and breakage can occur with the use of Teflon®
pipe joint compounds. Teflon®provides lubricity so that care must be
exercised not to over-tighten joints. Failure to follow these instructions
could result in property damage and /or personal injury.
CAUTION: Electrical shock hazard. Disconnect ALL power sources when
installing or servicing this equipment to prevent eletrical shock or
equipment damage. Failure to follow these instructions could result in property
damage and/or personal injury.
Caleffi shall not be liable for damages resulting from stress corrosion, misapplication or misuse of it products.
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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.

CONSIGNE DE SÉCURITÉ
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: Un serrage excessif et la rupture peut se produire avec
l’utilisation de composés à joint de tuyau en Téflon®. Pouvoir lubrifiant Teflon®
permet de sorte qu’il faut prendre soin de ne pas trop serrer les articulations.
Le non-respect de ces instructions peut entraîner des dommages matériels
et/ou des blessures.
ATTENTION: Risque d’électrocution. Appareil sous tension. Coupez l
’alimentation électrique avante d’effectuer toute i ntervention. Le non
respect de ces indications peut provoquer des lésions corporelles ou des
dégâts matériels.
Caleffi ne pourra être tenue responsable des dommages résultant de la corrosion, d’une mauvaise
utilisation ou une mauvaise utilisation des produits.
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AVERTISSEMENT: Ce produit peut vous exposer à des produits chimiques comme
le plomb, qui est connu dans l’État de Californie pour causer le cancer, dommages à la
naissance ou autre. Pour plus d’informations rendez-vous www.P65Warnings.ca.gov.

Installation:
To install the flow switch correctly follow these instructions:
- When selecting the blade, identify the diameter of the
pipe to which the appliance will be fitted;
- The appliance comes pre-fitted with the 1” blade;
- For diameters of 1 1/4” (DN 32) and above, the pre-
fitted blade should be removed and the l ong blade
fitted, cutting it to the correct corresponding size for
the desired diameter;
- Fit the flow switch to the pipe, carefully observing
the direction of flow indicated by the arrows stamped
on the cover and on the switch mounting plate. When
fitted, the distance between the upper surface of the
pipe and upper surface of the switch mounting plate
should be 3 1/8” (80 mm);
- The tee connection in the pipe can be formed by
the direct welding of a threaded socket;
- This also applies to a 1” (DN 25) diameter pipe,
as the blades are designed to be contained in these
smaller dimensions.
- It is however advisable to check that the weld is
free from burrs on the inside so that the blade can
move freely in the the connection;
- Whenever possible the flow switch should be installed
with control stem in the vertical position to avoid deposits
of impurities which may cause it to function incorrectly.
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Electrical Connections:
Unscrew the four cover screws and lift off the outer cover .
Flow switch used to activate a device when
flow stops. When the decreasing operating
flow is reached or stops the common (black
wire) and the normally open (red wire) contacts
open, while the common (black wire) and the
normally closed (blue wire) contacts close.
Flow switch is used to activate a device when
flow starts. When flow starts and the increasing
operating flow is reached or exceeded, the
common (black wire) and normallyopen (red
wire) contacts are closed, while the common
(black wire) and the normally closed (blue wire)
are open.
Diagrams showing the internal connections of the micro-switch with:
CAUTION: Make sure the wires do not obstruct the
function of the switch mechanism.
AVERTISSEMENT: Assurez-vous que les fils ne
sont pas entraver le fonctionnement de la changer le
mécanisme.
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CAUTION: In order to maintain NEMA 3 (IP54) protection of internal switching components, included
strain relief must be used.
AVERTISSEMENT: Afin de maintenir la protection NEMA 3 (IP54) des composants de commutation
internes, le serre-câble inclus doit être utilisé.

Electrical Rating:
Calibration:
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The minimum and maximum operating flow rates are given in the table below. Adjustments should
be carried out as follows: turn the calibration screw (A) i n a clockwise direction f or the contacts
to close at higher flow rate values or in a counterclockwise direction for lower flow rate values.
When the adjustment has been made lock the screw (A) with the locking ring nut (B). Avoid
all contact with the presetting screw (C). An incorrect setting would seriously impair the
operation of the switch.

Operating flow rates: gpm (lpm)
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Caleffi North America, Inc.
3883 West Milwaukee Road
Milwaukee, WI 53208
T: 414.238.2360 F: 414.238.2366
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NOTES
12-2022