RVK Fan making a noise

[Guest]

Hi all.

 

Just need a big of advice about an 8 inch RVK fan i have.

 

So its in the loft in a large padded MDF box, but recently when the fan is put on a lower setting (2 or 3 on my fan controller)  it seems like there is more vibration in the room below, and i can hear it more than i used to. On setting 4 or 5 its fine.

 

I am using an SMS hybrid, so its not Fan hum, its something else.

 

Is it possible the bearings need changing after 2 - 3 years use?

 

What do you think? 

Edited March 31, 2019 by Alan Johnson
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[Herbsman]

Be surprised if it is the bearings.  I have RVK's that are nearly 15 years old that are fine.

 

Have u checked the ducting for leaks or movement?

[Green fingered]

If it hard fixed to something it could be working lose. I doubt its the bearings also but theres not not alot that will course this, i used to work on 6ft extractors and they work differently but it sounds like; 

 

- its coming lose form its mounting point.

- fan belt slipping

- the bearing.

- the balancing of the fan blades are off. 

 

But given the type of fan i cant see it being the last three things

Edited March 31, 2019 by Green fingered

[Green fingered]

32 minutes ago, Herbsman said:

Be surprised if it is the bearings.  I have RVK's that are nearly 15 years old that are fine.

Bloody hell, so i guess you rate them then. All i have is a cheap thing i got of amazon when i started up 5 months ago, kind of waiting for it to die so i can get a sweet new one

[badbillybob]

I changed the bearings out of a big rvk fan, as it was kinda thrumming, if that's a word, it was kinda vibrating. 

 

it made no difference, it turned out the centre part of the fan was slightly off centre and was rubbing on the outer part of the housing (the centre housing, not the fan outer housing)

hope this makes sense. bottom line was the fan was fuct

[Guest]

So do you guys think i should potentially just replace it? 

 

its encased in MDF, with those sound proof tiles inside the box, and then the box is sitting on insulation, so i am struggling with why i am still getting vibrations.

 

Might just get a new fan? 

[nah]

Hi mate. What is the sound level when turned up on full? Mine makes more noise on halfway. Something to do with the power supply I reckon, you can research "noisey lighting dimmer pack" to understand the science (you'll get results from lighting guys in the events industry, but the electronics are the same). I haven't found a solution to my noise problem,  but maybe just even more sound proofing and acoustic decoupling even from your controller/power supply might help. Could look into anti vibration mounts.

[Joint hogger]

@nah  get a better fan controller which has a power transformer or a variac in it, the one your using atm which has an electronic version of a transformer in it & is called a triac, this is whats causing the hum (motor harmonics).

 

the cheapest is about £60--70 & is called a STR voltage stepping controller, its also only got 5 settings, if you want something with full control, build your own with a variac transformer in it, theres loads of info in the diy section, search for Variac.

[cannathc]

On 01/04/2019 at 9:49 PM, Alan Johnson said:

So do you guys think i should potentially just replace it? 

 

its encased in MDF, with those sound proof tiles inside the box, and then the box is sitting on insulation, so i am struggling with why i am still getting vibrations.

 

Might just get a new fan? 

 

It sounds like acoustic resonance to me.

Isolating the fan from the rest of the building is the key, so either hang the fan itself inside the box with elasticated rope, or hang the whole box from rubber "O-rings"

[Guest]

Upgraded to a vector EC fan. Noise stopped instantly. Great bit of kit