Grundfos Medium UPM Series Data Booklet page 4

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Medium UPM
Heat producers Heat consumers
Solar charging kit
Freshwater
Heating kit
station
Geothermal Solid fuel Gas fuel
heat pump boiler boiler
Underfloor
heating kit
Fig. 1 Complete domestic heating system combined with renewable energy sources
On the generation side, most pumps are externally
controlled via control signal ( PWM, LIN bus) by the
appliance control. The pumps on the distribution side
are often stand-alone pumps and mainly internally
controlled (AUTO version). The pumps in circuits with
variable flow are differential-pressure controlled either
as constant pressure (CP) or proportional pressure
(PP) control. In addition to 3 different control curves
each, there is the option to select the AUTOADAPT CP
or PP mode. With AUTOADAPT, the control curve is
automatically adapted to the actual requirements of the
respective application.
For domestic hot water systems, we must offer pumps
with stainless-steel housings that have the necessary
drinking water approvals like UBA, KTW, DVGW, ACS,
KIWA or WRAS.
For solar thermal systems, SOLAR PML pumps are
available, which are suitable for solar media containing
glycol up to 110 °C (peak). They use the PWM-C signal
profile, which is inverse of the PWM-A signal profile.
The PWM-C signal profile stops the pump and avoids
that the pump runs and overheats or unloads the
storage tank, if the signal is missing.
All medium UPM pumps are equipped with spacers to
decouple the terminal box from the motor. The motor is
protected against condensate in the stator with drain
holes. Therefore, all pumps can run down to minus
10 °C with antifreeze media mixtures.
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