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 model 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 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.
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 fitted 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 pipework from/to the valve must not be used to support
the weight of the valve itself.
