4-7 Others
If the air handling unit is installed or placed outdoor, you should take necessary measures to prevent the unit from being
affected with damp, rusted and dusted. Drain out all collected water in coil in order to prevent coil from being frozen and
damaged when unit stops running in winter.
V. Troubleshooting
1. Lower Air flow
When the actual external air pressure drop is bigger than the design pressure, the air flow will come down. Belt is loosened
so rotating speed of fan reduces, which makes air flow become lower.
2. Higher Air Flow
When the actual external pressure is lower than the design pressure, which makes air flow become higher. The higher air
flow is, the faster air speed is, and then the noisier the unit is.
3. Noise
Check return air and supply air duct to find whether they are connected with unit by flexible connection or not; Whether
anti-vibration is installed ; Whether air speed in blowing air opening is too big or not; Whether the parts and components are
loosened or not.
4. Broken Belt
Check belt tension to find whether it is too tight or not; Whether pulleys are not aligned; Whether the belt is worn out.
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Troubleshooting
