2-Way unmixed pump unit M2 DN32

2-Way unmixed pump unit


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


  • Connection.
  • Flanged ball valve with T-handle.
  • Circulating pump (for the models with it).
  • Flanged ball valve supplied with in-handle thermometer (coded red, range 0°C-120°C).


  • Flanged ball valve  supplied with in-handle thermometer (coded blue; 0°C-120°C).
  • Connection with 20 mbar non return valve (ball valve side).
  • 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 81 kW (with Δt 20 K) and maximum flow 3500 l/h.
Kvs Value: 21,0.
Approximate data calculated with a 8 m nominal lifting power circulating pump.
For an accurate measuring or for higher flows, please refer to the diagram.

Available circulating pumps:


Wilo Stratos PARA 30/1-7 (PA1-7)
Wilo Star RSG 30/8 (RSG8)*

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 o 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) - with circ. pump: 20555(R/L)-(PA1-7/RSG8)


“R” Codes: pump units with right supply. f.i. 20555R; “L”Codes: pump units with left supply. f.i. 20555L.
(*) The pump units with circulating pump Wilo RSG 30/8 (RSG8) are not reversible. They are available only with right supply 

  • Model: M2 DN32