Technical Service Bulletins; H4Xxx Cooling Fan Behavior; 4080 Bm Control Panel Fogging - Miele H 408 BM Series Technical Information

Technical Information
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Technical Service Bulletins

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H4XXX Cooling Fan Behavior

All Miele ovens are equipped with cooling fans. Their purpose and behavior
are not always completely understood. To avoid confusion and unnecessary
service visits, the following explanation should be used whenever dealing
with a customer or dealer inquiry.
The cooling fans in Miele ovens are primarily designed to remove heat from
the oven cabinet and keep the electronic components from overheating. A
secondary purpose is to prevent the buildup of moisture and condensation on
these electronic parts. This contributes to the reliability and longevity of the
oven. The cooling fan will always continue to run after the oven is switched
off. The amount of time that the fan runs is determined by sensors in the oven
and computer logic built into the oven's software. There is no formula or fixed
amount of time for this fan to operate. It's possible that the fan could run for
several hours. This is by design; there is nothing wrong with the oven.
Service note:
All oven cooling fans (including speed ovens) are equipped with a speed
sensor. This sensor is a Hall-effect semiconductor device and its proper
operation cannot always be determined using a multimeter. If an oven
refuses to heat, always remember to check the operation of the cooling fan at
all available speeds. If the electronic does not detect a signal from the fan,
the main heater relay (1K1, 2K1) will not energize. A good example of this
behavior can be illustrated with a speed oven. Microwave and Convection
modes use speeds 1 and 2 on the fan. Combi-Mode uses speed setting 3. If
for some reason the fan will not run when speed 3 is selected, only that mode
will not heat. Other modes will continue to function.
2 H 4080 BM Control Panel Fogging
In some instances, the control panel of a speed oven may begin to fog up on
the inside. This is usually the result of a heavy cooking cycle with high
moisture content in the food. If the customer finds this to be a recurring
problem, there is a fix for this:
1. Order part number 07093411 (seal).
2. Install the seal as illustrated below.
Note: The seal is longer than the cover plate and will need to be trimmed.
Be sure to install the seal with the 'bulge' facing down.
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H 408x BM