Shop heater vibration absorption?

[GASCo]

Hi guys,

Installed a bigmaxx shop heater last year. It worked amazing during the winter, but there is one downside.

It is attached to the rafter on the garage roof, and the roof is connected to the house. It ends up vibrating the structure and an annoying low pitch hum is generated in my bedroom.

I was thinking if somebody has any suggestion on how to decouple the heater from the structure. I thought about some kind of rubber or spring mounted connection to the structure. However, I couldn't find anything online. I'm sure I'll need to re-purpose something else to this function, but can't think of anything applicable.

Being that the heater is 60lbs and has 4 hanging rods, I found a catalogue of what would work: SNRC1-C22 spring hanger 0-30lbs, link below. This is perfect because, according to the spec sheet it would be a 50% spring compression at 50% load. Exactly what I have. However, I can't find it for sale anywhere. http://literature.puertoricosupplier.com/018/DS18024.pdf.

Found this one on Grainger, but a spring seems to be a much better solution.
https://www.grainger.com/product/MASON-Hanger-Mount-Vibration-Isolator-2LVR8

 

[rlitman]

Well, first off, if it's hanging, hang it from a chain. That eliminates the horizontal component of the vibration completely.

What we do here is put two pieces of Kindorf/Unistrut under the unit, with bolts on each end attached to chains that hang it. And then put rubber vibration isolaters between the unit and the Kindorf to reduce the vertical component of the vibration.

 

[GASCo]

Thanks rlitman. That makes sense. Right now it is bolted to the joist. I'll do chains as you suggested. It makes sense!

 

[nadogail]

Thanks for sharing.

 

[pbon]

Check the fan balance. A few have had vibration because the fan was not securely attached.

My Big Maxx 50 is bolted directly to my ceiling. No vibration. It’s a 130 year old 2 story carriage house so maybe the construction is less prone to vibration.

 

[TuxThePenguin]

Another thing you can do is use these sorts of brackets https://kineticsnoise.com/home/stud-wall-isolation.html

I have used them but I made my own. I got a roll of rubber from McMaster and I just sliced it. If you get soft rubber you can slice it with a ratcheting PEX pipe cutter. I used some relatively large angle brackets. In my case I was isolating a non-load-bearing wall and I screwed the angle brackets to the joist, then at the top board of the wall such that it went, in order from top to bottom:

screw head
washer
rubber bushing
bracket
rubber bushing
wall

perhaps you can even use some kind of rubber isolation in combination with a chain. Could probably install a hook like this for the chain or something, but the key is you want the rubber on both sides of your mount.

 

[GASCo]

Thanks for all the help guys. I got all the parts and will update when I install.

The noise in the bedroom is really low, but it is there. Not something that would bother me, but wife wasn't happy. For me to hear I'd need to really look for it, even being in the bathroom that is literally next to the heater on the other side of the wall.

 

[ripperd]

I hung mine on short springs as it is right below my sons bedroom. I also added short sections of safety chain about an inch longer than the spring to catch it if a spring breaks.

 

[frankd]

Check the fan balance. A few have had vibration because the fan was not securely attached.

My Big Maxx 50 is bolted directly to my ceiling. No vibration. It’s a 130 year old 2 story carriage house so maybe the construction is less prone to vibration.

+1 on checking the fan balance. I have a ceiling mounted heater in the garage as well and had vibration. I removed the fan and balanced it, problem solved.

 

[JamesDickie]

Well, first off, if it's hanging, hang it from a chain. That eliminates the horizontal component of the vibration completely.

What we do here is put two pieces of Kindorf/Unistrut under the unit, with bolts on each end attached to chains that hang it. And then put rubber vibration isolaters between the unit and the Kindorf to reduce the vertical component of the vibration.

Hi guys, I know this is an old thread. @rlitmanI I was wondering if there is any specific style of chain you used? I ordered these mounts https://www.amazon.ca/dp/B095VVYCF7?ref=ppx_yo2ov_dt_b_fed_asin_title . The heater is about 3 feet from the room so I was going to use eye bolts and chain between the mounts and heater.

Thank you,

James

 

[rlitman]

The twisted wire type used on inexpensive home swingsets would work. Steel double loop chain. #2 is probably overkill for anything but really large equipment (255lb WLL). #3 should suit you (90lb WLL).

#35 sash chain woulds also be an acceptable option, but it might be difficult to get a bigger hook into it's smaller holes. A welded lighting fixture chain that has a real Working Load Limit could work, but most chandelier chains aren't welded, so they're limited to VERY light hanging loads.

Those mounts look REALLY nice. The only thing I would say is you want as low weight rated an isolation mount as possible for what you're hanging. Heavier mounts use heavier springs that won't end up compressed as much, so as the weight rating goes up way higher than your equipment, the isolation efficiency drops off.

 

[ipgenie]

If you have a drywall jack, it makes the perfect platform to lift and support the heater while you work on changing the mounts or when installing a heater.

Not really any help for the OP since it was 4 years ago but good to bring up for those mounting or working on heaters this winter.

 

[JamesDickie]

Thanks folks. I appreciate all the help and advice.

 

[JamesDickie]

Got it all completed. Thanks for the help guys. It now is quieter than the furnace. The only thing I may still do is put some Loctite on the bolts going into the strut nuts in the unistrut. Want to make sure there is no chance of vibration loosening them.