ENGLISH
7 Maintenance
Before starting service or repair work switch off the plant and secure against
unauthorized switching.
Beware of sclading!
In the event of high temperatures and high system pressure, the pumps should
be allowed to cool down.
7.1 Mechanical seal
Slight may occur during the running-in period. Visual leakage checks are however re-
quired weekly. Distinctly visible leakage will require an exchange of the seal. WILO offers
a repair set containing all parts required for an exchange.
Exchange of the mechanical seal
(Fig. 4, 5,):
- Switch off power supply and secure against unauthorized switching.
-
Close isolating valves at both pump ports.
-
Lower the pressure of the pump by opening the air vent plugs (pos. 2.1).
Beware of sclading!
In the event of hot liquids,
-
Disconnect wires from motor terminals if cable length is too short for dismantling the
motor.
-
Unscrew the motor fixing-screws (pos. 4) at motorflange and lift the motor with impeller
and shaft seal off pumphousing by means of suitable lifting gear.
-
Unscrew the impeller fixing-nut (pos. 1.11) together with the plain washer (pos. 1.12)
and pull off the impeller (pos. 1.13) from the pumpshaft.
-
Remove mechanical seal (pos. 1.21) from shaft.
-
Carefully clean fitting/seat area of shaft.
-
Remove the stationary ring of the mechanical seal with seal collar from its seat in the
lantern flange, remove the o-ring (pos. 1.14) and clean the seat areas.
-
Press the new stationary ring of the mechanical seal with seal collar on its seat in the
lantern flange. Use ordinary liquid soap for lubrication.
-
Insert new o-ring into the groove on its seat of the lantern.
-
Push new mechanical seal up to the end of the conical seat right onto shaft. Use ordi-
nary liquid soap for lubrication.
-
Refit impeller with plain washer and nut, fix by the outer impellerdiameter. Handle care-
fully to save the mechanical seal.
ATTENTION!
Observe screw tightening torque regulations (see 7.3).
-
Remount the motor with impeller and shaft seal by means of suitable lifting gear and
secure the motorflange connection with bolts.
ATTENTION!
Observe screw tightening torque regulations (see 7.3).
-
Rewire power leads to motor terminals.
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