There is a constant 'mains buzz' coming from my unit especially when in night mode or turned off on the app. It is coming from the main fan.

When in night mode it sometimes seems to run for 10 seconds, then stops for a few minutes and then 10 seconds again....all night!

I read somewhere on Mr Google that the fan needs a shot of WD40, and cleaning, as does the small fan in the side sensor. Done that bit still there.

Anyone had this problem and possible solution please.

Had same problem with 3H. It was from small fan at the back for air quality sensor.

 

Didn't fix it, just bought a new one.

20 minutes ago, tomazbodner said:

Had same problem with 3H. It was from small fan at the back for air quality sensor.

 

Didn't fix it, just bought a new one.

Thanks, but no, I can hear it is coming from the main fan, as if it hasn't enough power to get going, even though it is. I can still hear it when the main fan is going fullspeed.

 

You could try contacting Mac Modern (the official LINE) for Xiaomi. They answer questions relating to the product.

21 minutes ago, KannikaP said:

Thanks, but no, I can hear it is coming from the main fan, as if it hasn't enough power to get going, even though it is. I can still hear it when the main fan is going fullspeed.

 

Maybe different in your case. On mine, main fan was making mosquito like noise that you didn't really hear unless you turned off the aircons. But even when the main fan was turned off, I still heard the noise for about 10 seconds every few minutes. Waiting for it, I found out that the intermittent noise was not coming from main fan but from the small fan at the back. The constant sound when the air cleaner was on was coming from the main fan.

 

There is a Xiaomi service center in Fortune Town, Mercure hotel side on 2nd floor, but on talking to them, and realising it would be service charge plus charge for parts, the repair would have come to about same price as buying a new one.

 

Apologies for not being more precise. I was responding to this part: "When in night mode it sometimes seems to run for 10 seconds, then stops for a few minutes and then 10 seconds again....all night! " That's the behaviour of the small fan which is testing air quality.

1 minute ago, tomazbodner said:

Maybe different in your case. On mine, main fan was making mosquito like noise that you didn't really hear unless you turned off the aircons. But even when the main fan was turned off, I still heard the noise for about 10 seconds every few minutes. Waiting for it, I found out that the intermittent noise was not coming from main fan but from the small fan at the back. The constant sound when the air cleaner was on was coming from the main fan.

 

There is a Xiaomi service center in Fortune Town, Mercure hotel side on 2nd floor, but on talking to them, and realising it would be service charge plus charge for parts, the repair would have come to about same price as buying a new one.

 

Apologies for not being more precise. I was responding to this part: "When in night mode it sometimes seems to run for 10 seconds, then stops for a few minutes and then 10 seconds again....all night! " That's the behaviour of the small fan which is testing air quality.

Thanks, exactly the same EXCEPT mine is in Phitsanulok.