How noisy are blower boxes for wet heating systems ?

[Bornslippy]

So after much deliberation we are installing a wet system (air heating ducts won't get past the water tank under the saloon on our '70's 45' ketch - please assume that the Webasto 90 will be a properly loaded pressurised system...and the fans will have ducted inputs from the space that they are heating. We'll eventually be sailing in colder climates all year around so a bit more power and hot water at anchor are requirements).

So...

How noisy are blower boxes for wet heating systems ? I'm looking at Sirocco Tenere and Kalori Evo1 ducted 3 speed blower boxes as there really isn't space for the grills on the much quieter silencio models, nor radiators, and a blower box will need to be installed under the sleeping area in the master cabin. Do I need to think about a noiseproofing solution? Is the noise acceptable on even the lowest fan setting? Are the Silencio's quiet enough (I know some have replaced the fans with the even quieter Noctua computer fan) ?

 

[snowbird30ds]

I don't know about any of the models mentioned but anything with a cage fan will be quieter than one with an axial fan, I have a blower in my cabin which runs off an engine that comprises a car matrix and inline bilge blower that is pretty noisy but still out done by the engine noise so not an issue, you wouldn't want it running at night though.

 

[Dockhead]

I have the Eberspacher ones. They are fairly noisy, but not noisier than an Eber air heater. No one can tell you what it will be like on your boat because it depends not only on the unit, but on the installation. Make sure and use rubber mounts to prevent sound transmission to the structure of the boat.

Make sure and get ones with variable speed fans and thermostatic control. Mine are just two-speed and no thermo control, so they run continuously.