How to make a fan silent in a bathroom. Budget solution
Forced ventilation is by definition a hell of a noisy thing. If we talk about the mass market, the fans generate a noise of about 30-35 dB (comparable to a quiet conversation). Yes, there are "silent" models. But, in my opinion, they are worth incommensurate to the effect they have. I even managed to make the budget model quieter "silent". At the end, I will demonstrate the result (sound) on video. I am sure this experience will be useful to someone.
Several important points
It is better to solve the problem of noisy ventilation in a complex manner. After all, the sound comes not only from the fan. There are several factors, for example:
- Installation of air ducts. Each break in the ventilation box adds noise to the system. If possible, avoid corners or make them smooth. Before installation, we remove the beads of plastic that may remain after casting. Each unevenness is a drop in the piggy bank of noise. A self-tapping screw screwed through into the vent box is a guaranteed whistle.
- Fan type. Among all the features, I pay attention to the engine. If assembled on bushings, wear, imbalance and noise will occur over time. Therefore, I take those that are on bearings.
- Air speed. The air itself, moving along the ventilation duct, creates a lot of noise. Therefore, a free-standing fan and a built-in fan make different noise. The higher the air speed, the more noise.
Taming the fan
I decided to get rid of the noise by reducing the speed of air movement. At first I wanted to put a dimmer instead of a switch. Yes, it is not very convenient to turn on the ventilation, but the buzzing above the ear was more annoying. Before that I decided to discuss such a move with an electrician.
The electrician told me for a long time that installing a dimmer is not the best solution. I do not presume to retell it in detail. He advised a different connection scheme.
I added a resistor and a capacitor to the fan power circuit. 1 MΩ resistor. The smallest is enough. The capacitor is non-polar, the voltage is from 400 V and above, the capacity is 0.3-0.8 μF. It is better to take several capacitors and select the required capacity experimentally. The fan speed will depend on it.
Performance drops after this improvement. If you are only going to buy a fan, it makes sense to take it with larger parameters. For example, we know that we need to provide 60 cubic meters of air exchange in the toilet, which means we take the fan for 120 cubic meters.
We connect the capacitor and resistor in parallel.
We install this assembly in a chain in series with the fan. I will show you how it looks in practice (scroll through the photo).
Perhaps in such a performance for some it will seem like a complicated installation. I have installed these items in a box. They do not take up much space and everything looks much simpler (scroll through the photo).
And the most important question - what is the effect of this modernization? I shot a video, I hope the Zen media player will correctly transmit the sound.
The fan is turned off first. Then I supply power through the capacitor (the indicator lights up). What do you hear? At the fifteenth second, I close the circuit directly. I think the difference is obvious.
Link to video: https://zen.yandex.ru/media/fishki_remonta/kak-sdelat-besshumnuiu-ventiliaciiu-zvuk-do-i-posle-sm-kommentarii-5e3c0b955a768b6aaa86979b
That's all for me. Thanks for reading. If the article was helpful, subscribe to the channel and of course put your thumbs up 👍.