Pressure Tanks - Grundfos BMQE 15 Product Manual

Handbook
Fault
5. The pump is running but
there is no pressure.
6. The pump does not deliver
enough water.
7. The pump has run for a
long time, but delivers no
water when restarted after a
standstill.
8. Pump switches on and off
frequently.

Pressure Tanks:

Keep the following tips in mind, when dealing with installations using pressure tanks:
• Stop the pump and open a valve to relieve the water pressure before checking the pre-charge pressure of
the tank.
• For traditional on/off controlled pumps, the pre-charge pressure should equal the cut-in pressure multiplied by 0.9.
Installation note:
You should always consult the Instruction and Operation manual for each specific pump during installation and start.
WebCAPS:
Find detailed information via the Grundfos website. WebCAPS is an easy to use on-line tool that enables users
to size systems and access general information about our products, where you can easily download the most
up-todate pump information.
Cause
a) The pump and/or suction pipe
is incorrectly primed.
b) The non-return valve or suction
pipe is leaky.
a) The suction lift is too high.
b) Pressure switch settings are incor-
rect
a) The pump and/or suction pipe is
emptied of water.
a) Pre pressure in pressure tank is
too low or too high.
b) Faulty foot valve.
c) The pressure switch differential
between the start and stop pressures
is too small.
Accessories
Remedy
Prime the pump and/or suction
pipe with water.
Replace the non-return valve
and/or seal the suction pipe.
Check the distance from the
pump to the water level in the
well. If possible, mount the
pump nearer the water level.
Adjust settings accordingly
Prime the pump and/or suction
pipe with water.
Adjust pre-pressure in pressure
tank. (0,9 x cut-in pressure)
Check footvalve, replace if nec-
essary.
Increase the differential.
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