Danfoss PAH 2, Installation, Operation And Maintenance Manual

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Data sheet PAH 2/4/6.3, PAH 10/12.5, PAH 20/25/32 and PAH 50/63/70/80/100 pumps
180R9379 | AQ188686503004en-000801 | PAH 2-12 .5 |
27 © Danfoss | DCS (im) | 2022.07 © Danfoss | DCS (im) | 2022.07
7.3 Open-system design
A Inlet line:
Dimension the inlet line to obtain mini-
mum pressure loss (large flow, minimum
pipe length, minimum number of bends/
connections, fittings with small pressure
losses and restrictions) .
B Inlet filter:
Install the inlet filter (1) in front of the PAH
pump (2) . Please consult the Danfoss filter
data sheet for guidance on how to select
the right filter .
C Monitoring pressure switch:
Install the monitoring pressure switch (3)
between the filter and the pump inlet . Set
the minimum inlet pressure according to
specifications described in item 4, technical
data . The monitoring pressure switch stops
the pump if inlet pressure is lower than the
set minimum pressure .
D Monitoring temperature switch:
Install the monitoring temperature switch
(4) between the filter and the pump, on
either side of the monitoring pressure
switch . Set the temperature value accord-
ing to technical data, item 4 . The monitor-
ing temperature switch stops the pump if
inlet temperature is higher than the set
value .
E Hoses:
Always use flexible hoses (5) to minimize
vibrations and noise .
F Inlet pressure:
In order to eliminate the risk of cavitation
and other pump damage, pump inlet
pressure must be maintained according to
specifications described in item 4, technical
data .
G Non-return valve (6):
Should be installed after the outlet to
prevent pump backspin, which may ruin
the pump .
H Pressure relief valve:
As the Danfoss PAH pump begins to create
pressure and flow immediately after
start-up regardless of any counter pressure,
a pressure relief valve (7) should be
installed to prevent system damage .
Note: If a non-return valve is mounted in the
inlet line, a low-pressure relief valve is also
recommended between the non-return valve
(8) and the pump to protect against high-pres-
sure peaks .
M
2
SYSTEM
1 4 5 5 6
7 3
PI PI
8