Grundfos ALPHA+ Series - Head Setting Adjustment

9
6.2 Change of head setting
Change the pump head by turning the selector
switch on the terminal box as indicated in the
table below:
Setting Result System
Factory
setting
Pump perform-
ance according
to the heating
demand
(in 80-90% of all
single-family
houses).
Variable-load heating
system with normal
resistance, with or
without thermostatic
valves.
Pump head is
reduced.
Variable-load heating
system with low
resistance, with or
without thermostatic
valves.
Pump head is
increased.
Variable-load heating
system with high re-
sistance, with or with-
out thermostatic
valves, or underfloor
heating system.
Also systems fitted
with a bypass valve.
Pump running
at minimum per-
formance.
Small constant-load
heating system.
Setting when adjust-
ing a bypass valve.
Pump running
at medium per-
formance.
Medium-sized
constant-load heating
system.
Pump running
at maximum per-
formance.
Large constant-load
heating system.
Setting when venting
the system.