Maintenance and repair
en
Installation and operating instructions Wilo-Padus UNI
39
ƒ
Decommission the pump immediately!
ƒ
Have the connection cable replaced by the customer service!
CAUTION! Material damage! Damaged connection cables cause
water to enter the motor. Water in the motor leads to total
damage of the pump.
9.5.2
Visual inspection of accessories
Accessories must be checked for:
ƒ
Correct fixation
ƒ
Smooth function
ƒ
Signs of wear, e.g. cracks caused by frequencies
Any defects detected must be repaired immediately or the ac-
cessories must be replaced.
9.5.3
Visual inspection of the coatings and housings
Coatings and housings must not show any damage. If there are
defects, observe the following:
ƒ
Repair damaged coating. Order repair kits from the customer
service.
ƒ
If housings are worn out, consult the customer service!
9.5.4
Function test of the monitoring device
To test resistances, the pump must be cooled down to the ambi-
ent temperature!
9.5.4.1 Test the resistor of the temperature sensor
‡
Ohmmeter available.
1. Measure the resistance.
⇒ Measured value
Bimetallic strip
: 0 ohms (passage).
▶ Resistance checked. If the measured value deviates from
the specification, consult the customer service.
9.5.5
Oil change in sealing chamber
WARNING
Operating fluid under pressure!
High pressure can build up in the motor! This pres-
sure is released when the screw plugs are
opened
.
• If screw plugs are opened without due caution,
they can be ejected at high speed!
• Hot operating fluid may spray out!
⇒ Wear protective equipment!
⇒ Allow the motor to cool down to ambient
temperature before carrying out any work!
⇒ Adhere to the prescribed sequence of work
steps!
⇒ Unscrew the screw plugs slowly.
⇒ As soon as the pressure escapes (audible
whistling or hissing of air), stop turning the
screw plug any further!
⇒ Only when the pressure has been completely
released, fully unscrew the screw plug.
1
Fig. 7:
Sealing chamber: Oil change
1
Sealing chamber screw plug
‡
Protective equipment used!
‡
Pump has been removed, cleaned and disinfected.
1. Place the pump on a firm work surface in a horizontal po-
sition. The screw plug should face upwards.
2. Secure the pump against falling over and slipping!
3. Unscrew the screw plug slowly.
4. When the pressure has been released, completely un-
screw the screw plug.
5. Position a suitable tank to collect the operating fluid.
6. Drain the operating fluid: Rotate the pump until the
opening points downwards.
7. Check the operating fluid:
⇒ Operating fluid clear: Operating fluid can be reused.
⇒ Operating fluid contaminated (black): fill with new
operating fluid.
⇒ Operating fluid milky/cloudy: Water in oil. Minor
leakage through the mechanical seal is normal. If the
ratio of oil to water is less than 2:1, the mechanical
seal may be damaged. Change the oil and check
again four weeks later. If water is again present in
the oil during the second check, contact customer
service!
⇒ Metal chips in the operating fluid: Contact the cus-
tomer service!
8. Pour in operating fluid: Rotate the pump until the open-
ing points upwards. Pour the operating fluid into the
opening.
⇒ Comply with the specifications for the operating
fluid type and quantity!
9. Clean the screw plug, replace the seal ring and screw it
back in.
Max. tightening torque: 8 Nm (5.9 ft·lb)!
9.5.6
Adjusting the impeller clearance
When pumping wastewater and sewage, wear can occur at the
impeller. This lowers the pump’s output. The clearance between
