2-way pump unit with electronic control for the constant temperature

2-way pump unit with electronic control for the constant temperature


The unit for 1 1/4” (180 mm) circulating pumps consists of:



  • Connection.
  • 3-way mixing valve with electronic servomotor.
  • Circulating pump with press-cable (for the models with it).
  • Flanged ball valve supplied with in-handle thermometer (coded red, range 0°C-120°C).
  • Temperature sensor



  • Flanged ball valve with non return valve 20 mbar (which can be excluded by rotating the handle by 45°) supplied with in-handle thermometer (coded blue; 0°C-120°C).
  • “T” Connection for mixing valve.
  • Connection.


Centre distance 125 mm. EPP insulation box (Measurements: 250x400x170 mm).

PN 10. Max Temperature 110°C.

External connections:  1”1/4 Female.




For power up to 52 kW (with Δt 20 K) and maximum flow 3000 l/h.

Kvs Value: 13,0.

Approximate data calculated with a 6 m nominal lifting power circulating pump.

For an accurate measuring or for higher flows, please refer to the curves shown in the technical section.


                 Available circulating pumps:

                   Wilo Stratos PARA 30/1-7 (P7)

                   Wilo Star RSG 30/8 (G8)*


The electronic servomotor includes a software that keeps constant the selected temperature of the supply way. The temperature is monitored by a PVC contact sensor (included) mounted on the supply way.
Adjustable temperature setting from 20°C up to 80°C. 
Minimum and maximum temperature limit are adjustable.
90° operating range. 
Power supply 230V, 135 s, torque 10 Nm. IP 40.


Typical curves of pump unit and circulating pumps



Balancing of overpressure (by-pass function)

In case the overpressure balancing function is required, it is necessary to use the model with the self-regulating circulating pump Wilo Stratos PARA 1-7, which, thanks to the integrated control of the differential pressure at constant ∆p or variable ∆p, allows to make equal the preformances and the efficiency of the M3 units in the DN25 series.
Code 1”1/4: 20555(R/L)-M3F-CT - with circ. pump: 20555(R/L)-M3F-(P7/G8)-CT
“R” Codes: pump units with right supply. f.i. 20355R-M3F-CT;
"L”Codes: pump units with left supply. f.i. 20355L-M3F-CT.
(*) The pump units with circulating pump Wilo RSG 30/8 (G8) are not reversible. They are available only with right supply way.




  • Model: M2 MIX3 FIX DN32