Application Of Silicon Grease To Athe Power Transistor And A Diode Bridge - Daikin FTXS30HVJU Service Manual

SiUS04-924
1.3 Application of Silicon Grease to the Power Transistor and
Diode Bridge
Applicable
All outdoor units using inverter type compressor for room air conditioner.
Models
When the printed circuit board of an outdoor unit is replaced, it is required that silicon grease (*1) is
applied to the heat radiation part (the contact point to the heat radiation fin) of the power transistor
and diode bridge.
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.
 Completely wipe off the old silicon grease from the heat radiation fin.
 Evenly apply the silicon grease to the whole diode bridge and power transistor.
 Do not have any foreign object such as solder or paper waste between the power transistor, the
 Firmly tighten the screws of the power transistor and the diode bridge to ensure contact to the
<Example>
Others
*1: Parts number of the silicon grease – 1172698 (Drawing number 3FB03758-1)
Remark: There is the possibility of failure with smoke in case of bad heat radiation.
diode bridge, and the heat radiation fin.
heat radiation fin without any gap.
Take out a PCB
OK : Evenly applied
silicon grease.
Power transistor
(TRM, TPM, IGBT, IPM, SPM, etc.)
Diode bridge
(Diode bridge, Rectifier stack, etc.)
Not applied.
NG : Not evenly NG : Foreign object.
applied
Other Considerations
Paper waste
(R9056)
185