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Magic-pak noise level 2

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kraiva

Mechanical
Jul 22, 2004
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We are designing an apartment high-rise with magic-paks for HVAC. The architect would like to see the magic-pak in a closet in the bedroom but I am not sure of the noise levels. Does anybody have any experience with this?
 
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IRstuff has the right website. But as you can see there is nothing on that to indicate the noise level for that.

Kind regards.
 
Don't know about Magic-Pak, per se, but I've lived in a 2-bdrm apt with a combo A/C-heater for about 980 sqft. It was pretty noisy, so I wouldn't recommend putting it in the bedroom.

Usually, these things are near the kitchen for access to the utilities or outside on the patio or balcony.

TTFN
 
I have looked at the basic info on magik pacs. Basically a fan in a box with ac. Lennox who make them are a reputable company and should be able to provide you with suitable noise data.
What you need are the SWL sound power data. From this you can estimate the ductborne and breakout noise. For the duct borne you could always fit an inline silencer (IAC Ltd. are best) and for the break out, simply place the unit in a well sealed room with a heavy access door.
Lennox would be best to advise. If you have a lot, I'm sure they could mock a typical room for you and the Client to see/hear.

PS IAC also do freebie calcs so they can advise on silencers etc. (They do free consultancy in the UK so they should where you are)

good luck

Friar Tuck of Sherwood
 
Sound data for these types of packaged units is relative to how it was taken, in a closet, in small or big room, indoor/outdoor. I have seen data anywhere from 55-60 dB for SkyMark's SkyPak to 70dB for Lennox's MagicPak.
MagicPak, SkyPak and other brand names are usually enclosed in a closet to reduce sound. The other factor is the way the unit is ducted. If there is a direct straight through return/supply it will obviously be noisier, versus a unit that has an elbow or two before the duct enters the conditioned space. As well, some units are quieter than others depending on whether they use prop fans or blowers, quality of acoustic insulation, and how it is built and how the other components are insulated.
I know of two major players, hope this helps.

 
You really need an acoustic expert to decipher the noise levels.

There are several ways to indicate the noise level. Some manufacturers 'play' on this and give the most flattering figures.
In essence, the most reliable method of fan noise comparison is the SWL Sound Power Level (Sound Watt Level)

If you use this criteria, then all manufacturers are on a level playing field.

As soon as you introduce 'typical noise levels', or Sound Pressure Levels (SPL) then you can disguise or mould the noise levels into whatever you like.


You can for instance say that a SPL sound pressure level for a unit is only 40dBA but this might assume a room size of 'X' and a duct connection with a bend and a particular grille size....all of which are variable.

The room might also have carpets, curtains, furniture etc.

How do you do a comparison of one manufacturer with another when they might assume a diffetnt duct connection, grille size, or size of room etc.

An acoustics engineer will do the calculation to convert the AC unit SWL INTO SPL by doind a few simple calcs. (Its pretty easy when you know how)

Remember, a fan will have a constant sound power level , no matter where it is installed so comparisons between manufacturers are easy. The sound pressure level though will depend on individual circumstances as already mentioned.

Friar Tuck of Sherwood
 
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