Circoflo PRO CFM-MXVP0111 User manual

Pump Mixing Unit
INSTALLATION GUIDE
CIG110

Pre-installation
The central mixing unit is a safety device to stop high temperature water from entering the underfloor heating
system. Water hotter than 60˚C must never be used in the underfloor heating system. If the heat source can
provide water at a temperature greater than 60˚C it is advised that a central mixing unit is used. The water must
be clean and treated before installation of the mixing unit.
The maximum underfloor heating area using a Circoflo system is 200m2. If larger areas need to be served, then
multiple units can be installed.
We advise that strainers are installed in the system to prevent debris from entering the mixing unit and
underfloor heating pipe. Also, if the water is very hard in the area, then installation of a scale reducer is
recommended.
Pack contents
Please check all components are present before assembly:
• Mixing valve with a temperature range from 30˚C to 60˚C (1). The mixing valve has 1 ½” connections (2) and (9)
for a circulator (not supplied) and three ¾” to 22mm compression adaptors (8) (supplied).
• Elbow with 1 ½” connection for circulator and a ¾” to 22mm compression adaptor. The elbow has a socket for
the temperature gauge (9).
• Temperature gauge to insert into the socket in the elbow for displaying the mixed water temperature (6).
• Four ¾” to 22mm compression adaptors (8).
• Circulator (10).
What is not supplied
• You will also need a standard domestic circulator, we recommend one with 6m head. If the system pressure
drop requires a higher performance circulator then this can be installed. The circulator (and boiler) will be
switched from the Circoflo controls.
• Connecting pipe work and fittings.
• Isolating valves.
• Four ¾” to 22mm compression adaptors (8).
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Pump Mixing Unit
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Pump Mixing Unit

Installation
• The central mixing unit can be sited anywhere on the primary before the underfloor heating manifolds.
• The mixing unit can be installed in either a horizontal or vertical position, however consideration must be given
to the circulator manufacturer’s instructions.
• The connections on the mixing unit are shown:
H = HOT (High temperature connection from the boiler) (4)
C = COLD (Return from the underfloor heating and to the boiler) (5) from UFH (3) to boiler
MIX = Mixed water outlet with water at the correct temperature for the underfloor heating (7)
• Adaptors are provided for 22mm compression connection Please ensure that the pipe work and mixing unit is
properly supported.
• Isolation valves and a bypass to be fitted as required depending on the boiler and system setup.
• Ensure that the system is free from debris. We recommend that strainers are installed to prevent debris from
entering the mixing unit.
• With the mixing unit installed and connected to the primary pipework and the circulator (10) fitted, the mixing
valve can be set to the required temperature. This is done by partially unscrewing the mixing valve knob screw (1)
and turning the knob clockwise to reduce the water temperature and anti-clockwise to increase the water
temperature. The settings and corresponding temperatures from the table below are approximate. The
temperature should be checked on the temperature gauge (6) (wait for the temperature to settle) and the setting
adjusted to achieve the desired flow water temperature. The temperature gauges at each manifold should also
be checked, if there a drop in water temperature then the setting at the mixing valve should be increased.
• The water temperature going into the underfloor heating pipe should never exceed 60˚C and should not be set
for continuous running higher than 55˚C.
• The valve is pre-set to 45˚C. This may be too low for some underfloor heating systems.
All temperatures approximate
• Once the temperature has been set, tighten the screw (1) to lock the setting.
• Check the mixed temperature from time-to-time to ensure that the system is operating as it should.
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Pump Mixing Unit

Pump Mixing Unit

Troubleshooting
The mixed water temperature is too low
• Check the that the temperature from the heat source is high enough
• This should be at least a few degrees higher than the required mixed water temperature.
• Check that the mixing unit is operating properly, debris in the unit will cause the mixing valve not to open and
close properly.
Underfloor is not working but mixed water temperature is correct
• Check the circulator at the mixing unit is operating.
• Check the thermostat and actuator valve at the manifold is working correctly, if not check the wiring and
thermostat program –see manifold and thermostat instructions
• Make sure the underfloor heating circuits are balanced.
• If the water temperature is too low at the manifold then increase the mixing valve setting. Flow and return pipe
to the manifold may have to be lagged if the temperature drop is too high.
• If the manifold is located far from the mixing unit the pressure drop may be too high, in this case a larger
capacity pump may be needed.
Circulator not working
• Check the switched power supply for the circulator from the Circoflo control system is correct. The circulator
(and boiler) should activate when there is a call for heat from a thermostat.
Technical information
• Temperature range 30˚C to 60˚C
• Maximum working temperature 90˚C
• Factory pre-set 45˚C
• Maximum static pressure 10 bar
• Suitable fluid: Max 50% glycol
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Pump Mixing Unit