AQUAPUMP VARIABLE SPEED CIRCULATING PUMPS
33-00543EF—03
6
Auto (underfloor heating and two-pipe (parallel systems)
Auto function observes and adjusts the pump performance
to satisfy the system requirement. The pump adapts to the
system over time, it is recommended to leave the pump in the
auto position at least one week before selecting other pump
settings.
Changing from recommended (auto) to alternative pump set-
ting:
Heating systems are 'slow' systems that cannot be set to the
optimum operation within minutes or hours.
If the recommended pump setting does not give the desired
comfort in some areas of the building, change the pump
setting to the shown alternative.
See pump settings and pump performance (section 9) for
more details.
Fig. 10. Recommended pump setting for different system type
7. SYSTEMS WITH BYPASS VALVE
BETWEEN FLOW AND RETURN
PIPES
7.1 PURPOSE OF BYPASS VALVE
The purpose of a differential pressure bypass valve is to
ensure that the heat from the boiler can be distributed when
all valves in the underfloor-heating circuits and/or
thermostatic radiator valves are closed. These valves were
commonly applied in multi zone systems with traditional
fixed speed pumps.
An AquaPUMP variable speed circulator eliminates the need
for a differential bypass valve when used in Auto or
proportional pressure modes, because the circulator will
reduce speed when the valves in the system close and the
heat demand is reduced.
If you are servicing an existing system with a bypass valve
and you are replacing a fixed speed circulator with an
AquaPUMP variable speed circulator, there is no need to
remove or open/ close the bypass valve, if you intend to set
to a constant pressure mode (PC3 / PC4).
It is recommend to remove the bypass valve if you intend to
use Auto or proportional pressure modes, because the
circulator will reduce speed when the valves in the system
close and increase the efficiency of the system operation.
8. START-UP
8.1 BEFORE START-UP
Fill the system with liquid and properly vent the system
before starting the pump. The required minimum inlet
pressure in relation to liquid temperature must be available at
the pump inlet (see section 11).
speed
pressure curve
ok
a
b
c
ok
ok
ok
ok
ok
radiant heat
system
gas or oil
boiler
auto
speed
pressure curve
auto
speed
pressure curve
auto
speed
pressure curve
auto
speed
pressure curve
auto
speed
pressure curve
auto
single zone - constant resistance
recommended
alternative
alternative
recommended
alternative
multiple zone - variable loads parallel
multiple zone - variable loads in series
recommended
