5. Fault finding chart
Fault
1. Motor does not start.
2. Thermal relay trips
out after short time
of operation.
3. Pump runs but gives
insufficient water.
4. Pump runs but gives no
water.
6. Disposal
Disposal of this product or parts of it must be carried
out according to the following guidelines:
1. Use the local public or private waste collection
service.
2. In case such waste collection service does not
exist or cannot handle the materials used in the
product, please deliver the product or any haz-
ardous materials from it to your nearest Grundfos
company or service workshop.
Cause
a) Supply failure.
b) Pump switched off by float switch/vertical level switch.
c) Fuses are blown.
d) Thermal relay has cut out the electricity supply to the motor
(see section 2. Electrical connection).
a) Temperature of pumped liquid higher than that stated in section
1.2 Operating conditions.
b) Pump partly blocked by impurities (see section 4. Operation and mainte-
nance).
c) Pump mechanically blocked (see section 4. Operation and maintenance).
a) Pump partly blocked by impurities (see section 4. Operation and mainte-
nance).
b) Discharge pipe/hose partly blocked. Check the non-return valve, if fitted.
c) Check the impeller, the pump housing and the sealing part (see section
4. Operation and maintenance).
d) Three-phase pumps only: Incorrect direction of rotation
(see section 2.1 Checking of direction of rotation).
a) Pump blocked by impurities (see section 4. Operation and maintenance).
b) Non-return valve, if fitted, in discharge pipe/hose blocked in closed position.
c) Liquid level is too low. During normal operation, the liquid level must be
above the strainer.
d) Pumps with float switch: The free cable of the float switch is too long
(see section 3.3 Adjustment of float switch).
Subject to alterations.
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