Daikin ATXS35EV1B7, Service Manual

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Others SiBE04-824
220 Others
1.3 Application of Silicon Grease to a Power Transistor and
a Diode Bridge
Applicable
Models All outdoor units using inverter type compressor for room air conditioner.
When the printed circuit board of an outdoor unit is replaced, it is required that silicon grease
(*1) is certainly applied to the heat radiation part (the contact point to the heat radiation fin) of
the power transistor and diode bridge.
*1: Parts number of the silicon grease – 1172698 (Drawing number 3FB03758-1)
Details The silicon grease is an essential article for encouraging the heat radiation of the power
transistor and the diode bridge. Applying the paste should be implemented in accordance with
the following instruction.
Remark: There is the possibility of failure with smoke in case of bad heat radiation.
„
To completely wipe off the old silicon grease on a heat radiation fin.
„
To evenly apply the silicon grease to the whole.
„
Do not have any foreign object such as solder or paper waste between the power transistor,
the diode bridge and the heat radiation fin.
„
To firmly tighten the screws of the power transistor and the diode bridge, and to surely
contact to the heat radiation fin without any gap.
<Example>
Take out a PCB
Diode bridge
(Diode bridge, Rectifier stack, etc.)
Power transistor
(TRM, TPM, IGBT, IPM, SPM, etc.)
Not applied. Paper wastage
OK : Evenly applied
silicon grease. NG : Not evenly
applied NG : Foreign object.
(R7100)