R-Pro › Field cases › Components
Indoor Unit Blower Bearing Wear → Characteristic Frequency Peak in Spectrum Analysis
Likely causes
Bearing lubrication shortage (grease depleted) → BPFO/BPFI frequency peaks
Check: Press stethoscope rod (screwdriver handle) against bearing area and listen — 'grinding' sensation indicates replacement; check for abnormal peaks in 1 kHz, 3 kHz, 5 kHz bands with smartphone noise app
What to do: Check for grease nipple — replenish with NLGI Grade 2 grease if accessible; if noise persists or recurs within 3 days, replace bearing with equivalent (manufacturer number); use dedicated tool during replacement (no hammering) — verify shaft squareness and interference fit
Indoor condensate water ingress — accelerated bearing corrosion
Check: Check for condensate traces around bearing (rust, white residue); inspect drain pan (blockage, cracks); identify poor insulation areas
What to do: Block condensate water ingress path (clean and repair drain pan, reinforce insulation); use waterproof grease when replacing bearing; apply anti-corrosion treatment to bearing cover
Bearing noise can be judged in 10 seconds with a stethoscope rod — if it recurs within 3 days after grease replenishment, replace immediately.
All 565 cases work offline in R-Pro, with error codes for 62 brands and P-T data for 108 refrigerants.
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