Arlec Energy Efficient 20cm Exhaust Fan Questions & Answers

These fans are terrible. They have no (ramping) in the fan as the $5 more HPM ones do. This causes the motor to start at full speed which nearly tears the housing apart. That is what the horrible noise is. I thought I had a bad one. I replaced it at Bunnings and the next one was the same. I took the second one back as well and bought a HPM which starts up slowly and smoothly until it is at top speed. We can turn the switch off and on repetitively and there is not a noise at all. For a toilet or bathroom the ARLEC fans won't last long. Worst ceiling extraction fans on the market.

Many thanks, will need to investigate further.

To put it simply, it uses an AC synchronous motor that, in this case, synchronises with line frequency by oscillating the hub against a one way spring to kick it into rhythm.