Miele G 7881 Service Manual

							2.6 Level Switches
2.6.1 Float Switch B8/3
If a water intake hose should leak, the leaking water flows along the outer hose
sleeve to the drip pan in the bottom of the machine. When a certain quantity of
water has collected in the drip pan, float switch B8/3 (050 Fig. 1, Pos. 8) acts to
stop the water flow by closing the WPS solenoid valves Y1, Y12 and/or Y20,
resulting in fault codeF 26(070 Table 51). At the same time, the drain pump is
activated to remove the wash water from the cabinet.The drain pump demand
is greater than the incoming water flow rate.This also applies when one of the
solenoid valves does not close correctly and supply water flows constantly into
the cabinet. When water flows out of the cabinet overflow into the drip pan, float
switch B8/3 will act to switch the water supply off and the drain pump on.
Because the leaked water in the drip pan cannot be removed automatically, the
machine will remain blocked until the water has been cleared.
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Warning!
The WaterProof System only operates with the door closed and the machine
turned on.
2.6.2 Heater Level Switch B1/10
The heater level switch (050 Fig. 1, Pos. 3) is connected directly to the circulation
pump (050 Fig. 1, Pos. 3), and registers the water pressure when the pump is
operating. When the pump is running and sufficient water is present, level switch
(changeover contact) B1/10 closes and the electronic then activates the heater
relay during the appropriate program segments.
2.6.3 Overflow Level Switch B1/1
As a safety measure to prevent overflows, overflow level switch B1/1 (050 Fig. 1,
Pos. 6) is linked to the Live 1 connection to the WaterProof system valves Y1, Y12
and Y20. If the cabinet is full, the overflow level switch acts to open the valve
circuit.
Descriptive Technical Documentation
DTD no. 62-7881 050-5
18.09.2013, US_am This information should not be duplicated or passed on without Miele approval. All rights reserved. 
						

							2.7 NTC Temperature Sensors
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NTC Sensor Resistance Values
Temperature (°F) Temperature (°C) Resistance (kΩ)
32 0 Approx. 35.9
41 5 Approx. 28.5
50 10 Approx. 22.7
59 15 Approx. 18.2
68 20 Approx. 14.7
77 25 Approx. 11.9
86 30 Approx. 9.7
95 35 Approx. 8.0
104 40 Approx. 6.6
113 45 Approx. 5.5
122 50 Approx. 4.6
131 55 Approx. 3.8
140 60 Approx. 3.2
149 65 Approx. 2.7
158 70 Approx. 2.3
167 75 Approx. 1.9
176 80 Approx. 1.7
185 85 Approx. 1.4
194 90 Approx. 1.2
199 93 Approx. 1.1
203 95 Approx. 1.0
Table 2:NTC Sensor Resistance Values
Descriptive Technical Documentation
050-6 DTD no. 62-7881
This information should not be duplicated or passed on without Miele approval. All rights reserved. 18.09.2013, US_am 
						

							3 Fault Repair
3.1 Heating Level Switch Does Not Switch On
Cause
Heating level switch does not react to water pressure.
Remedy
ACheck the switching point and continuity of the heating level switch.
AReplace the heating level switch, if necessary.
Cause
Excessively foaming detergent or rinse aid in the wash water. This reduces the
wash water pressure developed by the circulation pump and applied to the
heating level switch.
Remedy
AUse a different detergent or rinse aid.
3.2 Premature Failure of Circulation, Dispenser or Drain Pump
Symptom
After a short period of operation the pumps listed leak and seals swell up.
Cause
Possible dispensing of rinsing agent in the final rinse in order to lubricate metal
joints in the items being processed. If the rinsing agent contains paraffin oils, the
lifetime of components with a sealing function is reduced.
Remedy
AAvoid using rinsing agents that contain paraffin oils.
AUse a Miele-approved rinsing agent.
AAvoid automatic lubrication, i.e. do not dispense such agents in the machine.
AAs an alternative, lubrication of processed items should be carried out
manually with an aerosol after the load has been removed from the machine.
Descriptive Technical Documentation
DTD no. 62-7881 050-7
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Note
To protect seals, do not use disinfecting, alkaline detergents with a high
proportion of active chlorine at temperatures above 176°F (80°C).
3.3 Circulation Pump Does Not Start
Cause
Circulation pump motor winding too hot and the winding protection device 1F3
has tripped (it resets automatically after about 10 minutes). Foreign objects may
be blocking the pump.
Remedy
ACheck the circulation pump for correct operation; see 070 2.9.3S 23,
Checking Outputs 1 to 11.
ACheck the circulation pump connection plug at the electronic (070 Fig. 5, Pos.
17).
ACheck the circulation pump housing for foreign objects, jammed motor, etc.
Remove the pump housing, if necessary.
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Danger!
Be careful. Broken glass or similar could be in the pump impeller chamber and
could cause injury.
Cause
Operating capacitor C6 defective.
Remedy
ACheck the plugs on the operating capacitor and the motor block for correct
installation.
AReplace operating capacitor C6, if necessary.
Descriptive Technical Documentation
050-8 DTD no. 62-7881
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							4 Service
4.1 Speed Sensor B3/9 Check
AActivate the circulation pump in service mode 2 (070 2.9.3S 23, Checking
Outputs 1 to 11).
AIf the circulation pump starts briefly (3 start attempts) and then stops, then the
speed sensor is not providing any pulses (display flashes).
4.2 NTC Temperature Sensor Replacement
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Fig. 2:Temperature Sensor with Housing
AService Panel Removal, 022 4.2.
AToekick Removal, 010 4.6.
ARemove the holding bracket (080 Fig. 4, Pos. 2) by removing the retaining
screws (080 Fig. 4, Pos. 1).
ADisconnect the temperature sensor electrical connection.
AUse a suitable open-ended wrench to grasp the holder, and remove it from the
bayonet fitting. See050 Fig. 2, Pos. 2.
APull the temperature sensor out of its seal. See 050 Fig. 2, Pos. 3.
AReassemble by following these instructions in reverse order.
Descriptive Technical Documentation
DTD no. 62-7881 050-9
18.09.2013, US_am This information should not be duplicated or passed on without Miele approval. All rights reserved. 
						

							4.3 Drain Pump Removal
AService Panel Removal, 022 4.2.
ARemove the left side panel (Side Panel Removal, 010 4.1), if possible.
ARemove the terminal block mounting bracket.
ATwist the pump clockwise to unlock; remove the red clip, if applicable (usually
found on older models).
ADisconnect the electrical connection.
APull the pump out of the machine.
4.4 Sump Removal
ATilt the machine onto its right side.
ARemove the bottom pan.
ARemove the heater relay mounting bracket.
ADisconnect the drain pump hose and circulation pump hoses from the sump.
Move both pumps out of the way.
ATake off the float switch assembly.
ADisconnect the temperature sensors from the sump.
ARemove the sump from the machine.
4.5 Float/Float Switch Removal
ATilt the machine onto its right side.
ARemove the bottom pan.
ADisconnect the electrical connection from the float switch.
ARelease the float housing; open the housing and take out the float.
Descriptive Technical Documentation
050-10 DTD no. 62-7881
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							4.6 Circulation Pump/Speed Sensor Removal
ATilt the machine onto its right side.
ARemove the bottom pan.
ADisconnect the sump hose in front of the circulation pump.
ADisconnect all visible hoses from the pump (one is connected to the heater
pressure switch).
ADisconnect the speed sensor wiring harness (red/yellow).
ADisconnect the electrical connection from the circulation pump.
ARemove the 8mm bolt securing the circulation pump to the machine rear
panel.
ATake the pump out and unclamp a third hose.
ATake off the plastic bracket and take out the rubber gasket.
ARemove the speed sensor (magnet slides out of pump housing; board is
secured with a bolt to the pump housing).
4.7 Heater Pressure Switch Removal
ATilt the machine onto its right side.
ARemove the bottom pan.
ADisconnect the sump hose in front of the circulation pump.
ADisconnect all visible hoses from the pump (one is connected to the heater
pressure switch).
AUnclamp the hose connecting the heater pressure switch to the circulation
pump.
ATake out the heater pressure switch.
Descriptive Technical Documentation
DTD no. 62-7881 050-11
18.09.2013, US_am This information should not be duplicated or passed on without Miele approval. All rights reserved. 
						

							061 Air Vent, Cabinet Ventilation
G 7882 CD, G 7883 CD
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Descriptive Technical Documentation
DTD no. 62-7881 061-1
18.09.2013, US_am This information should not be duplicated or passed on without Miele approval. All rights reserved. 
						

							1 Technical Data
Technical data currently not available.
Descriptive Technical Documentation
061-2 DTD no. 62-7881
This information should not be duplicated or passed on without Miele approval. All rights reserved. 18.09.2013, US_am 
						

							062 Steam Condenser
G 7881, G 7882, G 7883
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Descriptive Technical Documentation
DTD no. 62-7881 062-1
18.09.2013, US_am This information should not be duplicated or passed on without Miele approval. All rights reserved.