Grundfos CR 1s Instrucciones De Instalación Y Operación página 31

Problem Possible cause
2. The pump runs but at a) Wrong direction of rotation.
reduced performance or
does not deliver water.
b) Pump is not primed or is air-bound.
c) Strainers, check or foot valves are clogged.
d) Suction lift too large.
e) Inlet and/or outlet pipes leaking. (Pump spins
f)
g) Pump impeller or guide vane is clogged.
h) Incorrect drain plug installed.
i)
3. Pump cycles too much a) Pressure switch is not properly adjusted or is
b) Level control is not properly adjusted or is
c) Insufficient air charging or leaking tank or piping.
d) Tank is too small.
e) Pump is oversized.
backwards when turned off)
Pump worn.
Improper coupling setting.
defective.
defective.
Remedy
Check wiring for proper connections. Correct
wiring.
Turn pump off, close isolation valve(s) and
remove priming plug. Check liquid level. Refill
the pump, replace plug and start the pump. Long
inlet lines must be filled before starting the
pump.
Remove strainer, screen or check valve and
inspect. Clean and replace. Reprime pump.
Install compound pressure gauge at the inlet
side of the pump. Start pump and compare
reading to performance data. Reduce suction lift
by lowering pump, increase inlet line size or
removing high friction loss devices.
Air in inlet pipe. Inlet pipe, valves and fittings
must be airtight. Repair any leaks and retighten
all loose fittings.
Install pressure gauge, start pump, gradually
close the outlet valve and read pressure at
shutoff. Convert measured pressure (in psi) to
head (in feet): (Measured psi x 2.31 ft/psi = ___
ft). Refer to the specific pump curve for shutoff
head for that pump model. If head is close to
curve, pump is probably OK. If not, remove
pump and inspect.
Disassemble and inspect pump passageways.
Remove any foreign materials found.
If the proper drain plug is replaced with a
standard plug, water will recirculate internally.
Replace with proper plug.
Check/reset the coupling. See page 18.
Check that pressure switch is set and functions
correctly. Check voltage across closed contacts.
Readjust switch or replace if defective.
Check that level control is set and functions
correctly. Readjust setting (refer to level control
manufacturer's data). Replace if defective.
Pump air into tank or diaphragm chamber.
Check diaphragm for leaks. Check tank and
piping for leaks with soap and water solution.
Check air-to-water volume. Repair as
necessary.
Check tank size and air volume in tank. Tank
volume should be approximately 10 gallons for
each gpm of pump performance. The normal air
volume is 2/3 of the total tank volume at the
pump cut-in pressure. Replace tank with one of
correct size.
Install pressure gauges on or near pump inlet
and outlet ports. Start and run pump under
normal conditions, record gauge readings.
Convert psi to feet (Measured psi x 2.31 ft/psi =
____ ft) Refer to the specific pump curve for that
model, ensure that total head is sufficient to limit
pump delivery within its design flow range.
Throttle pump outlet flow if necessary.
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