If your vacuum cleaner is making a high-pitched sound, yet there are no obvious clogs and the brushes are spinning at full speed, while also experiencing no suction, there could be several potential issues:
Internal clog or blockage: Even if you don't see any visible clogs from the outside, there could be a blockage somewhere inside the vacuum cleaner's hoses, filters, or tubing. Try to dismantle the vacuum cleaner according to the manufacturer's instructions and carefully inspect all components for any hidden blockages.
Hose or tubing damage: Check the hoses and tubing for any signs of damage or kinks. If they are bent or torn, it could disrupt the airflow and cause the vacuum to lose suction.
Filter issues: Dirty or clogged filters can greatly reduce a vacuum cleaner's suction power. Make sure to clean or replace the filters, as instructed in the user manual.
Motor issues: If the vacuum cleaner's motor is malfunctioning or damaged, it may not be able to generate enough suction, and the high-pitched sound could be an indication of strain on the motor.
Belt problems: Some vacuum cleaners use belts to drive the brush roll. If the belt is broken, loose, or misaligned, it could cause the brush roll to spin but not engage properly with the carpet, leading to reduced suction.
Bag or dustbin full: If your vacuum cleaner uses a bag or dustbin to collect debris, it may be full or close to full. Empty it and try again.
Air leaks: Check for any air leaks in the vacuum cleaner's body or hoses, as air leaks can disrupt the airflow and cause a loss of suction.
If you've gone through these troubleshooting steps and still cannot identify or resolve the issue, it might be best to contact the manufacturer's customer support or take the vacuum cleaner to a professional repair service for further examination and repairs. Remember always to follow the manufacturer's instructions and safety guidelines when troubleshooting or repairing any electrical appliance.