Putting router, switch, etc in attic. Hear me out

[Jmonnty]

Sorry for having to ask, but what is "PWM". Otherwise an interesting thread.



.

Pulse width modulated, how the fan speed can be variable speed.

 

[niget2002]

I won't debate the merits of the task... your mind seems made up.

I will just say that most fans do better at blowing air than sucking. No need to do a push/pull. Just put all fans on the blowing side with adequate exhaust holes for the air to go out of.

I have two large AC fans on my fish tank. The bigger fans turning at slower RPMs are much quieter than smaller fans at high RPM. Even with two of them on the tank, you can barely hear them running.

 

[TT_Vert]

Yeah that's why I went with 200mm fans. I considered AC fans but felt DC was a safer option.

I won't debate the merits of the task... your mind seems made up.

I will just say that most fans do better at blowing air than sucking. No need to do a push/pull. Just put all fans on the blowing side with adequate exhaust holes for the air to go out of.

I have two large AC fans on my fish tank. The bigger fans turning at slower RPMs are much quieter than smaller fans at high RPM. Even with two of them on the tank, you can barely hear them running.

 

[lml999]

I should have my digital thermostat here in the next few days and I can test out MKI.

You can get an indoor/outdoor wireless thermometer on amazon for about $15. I have the older Radio Shack/Oregon Scientific model which provides 3 outdoor channels. I keep a sensor on the back porch for outside temps, and a sensor in each part of my attic.

 

[scraejtp]

Yes and no. Those controllers you show are off or on. If you can control rpm based on temp you don't need the fan at full jet engine all the time. With that said, what you linked is what I'm starting out with.

Dave

You are not installing in a location where noise is an issue. Fans are typically designed to be most efficient (CFM/watt) at or near full speed. Running lower speeds is not worth it, and instead just let the controller turn them on/off as needed.

 

[Mecha]

Considered a Mesh network? They work pretty awesome.

 

[TT_Vert]

Considered a Mesh network? They work pretty awesome.

I use unifi APs which can be set up that way. Got the sides all squared away and after powering on one of those brushless 200mm fans I decided MKI is going to be a single 200MM fan. Started to mock up electronics just to ensure it all worked as designed which it does. I decided to use a pc power supply I had laying around to feed 12Vdc to the thermostatic fan controller, the fan and some switched LEDs I'm going to put inside of the cabinet if they are ever needed. I may also put a few 120mm fans up front to help exhaust hot air if need be. Or use that second 200mm fan I purchased to to the same thing.

i plan to use a ceiling duct box attached to the back of my rack where the fan is and probably something similar on the ceiling of the garage or wherever I source my intake from. But since no HD has these in stock I am temp going to try this and if the diameter is close to the fan diameter (It seems to be .2" different) I could use this more effectively. Either way I can easily seal this to ensure all air goes into the rack.

Few pics, will get pics of rack and more when I have it assembled.

Few pics

 

[Outlander]

Maybe this would dissuade the OP to put network equipment in the attic

https://www.garagejournal.com/forum/showthread.php?t=390808

 

[penright]

Seems like something I read, this was over the garage?
As you build the box and plum it for air, really think about the CO (carbon monoxide). Make sure that no air from the garage can get to attic. You did mention that front of the box would be open, that would be an issue. Can you add a door?

If you ever try and sell the house, inspectors are picky about air between garages and attics. Again, it's more of a CO issue, at least that what they told me. I had a couple of holes in my old house that they wanted fixed before I could sell it. I just bought some remodeler boxes, installed them empty and put on a cover that had no holes.

I was thinking about putting a UPS in the attic at the new house. The power to my network closet originates there in a junction box. My plan was to split off the junction box. Add a duplex outlet next to the junction. Then bring the old leg into a junction box, with a SO cord with a plug. Then I could plug the UPS into the outlet and the SO into the UPS. If the UPS goes down, bypass the UPS by plugging the SO into the outlet. The point... At work we have a lot of electronic equipment in closets in kitchens. We have heat issues there and they are somewhat climate controlled. I have the luck of my heater closet is off the two car garage. So my plan B is to mount a shelf for the UPS. Then instead of mounting the outlet next to the junction and the SO junction box, move it to the ceiling of the water closet. The outlets and face covers would isolate the air between the spaces.
Also, the new location gives me a chance to move the outlet for the garage door opener to the UPS. It would be nice to have a battery backup for the garage door, just not sure how much electrical noise it's motor would put out. Need more thought on that one.

 

[LifeLongWNYer]

Thanks, JWMonnty. I should have known that. I remember that term from my days in the Army, when it was used to describe a parameter of radar signal, but had no idea it now applies to controlling motors. Interesting.


.

 

[TT_Vert]

Seems like something I read, this was over the garage?
As you build the box and plum it for air, really think about the CO (carbon monoxide). Make sure that no air from the garage can get to attic. You did mention that front of the box would be open, that would be an issue. Can you add a door?

If you ever try and sell the house, inspectors are picky about air between garages and attics. Again, it's more of a CO issue, at least that what they told me. I had a couple of holes in my old house that they wanted fixed before I could sell it. I just bought some remodeler boxes, installed them empty and put on a cover that had no holes.

I was thinking about putting a UPS in the attic at the new house. The power to my network closet originates there in a junction box. My plan was to split off the junction box. Add a duplex outlet next to the junction. Then bring the old leg into a junction box, with a SO cord with a plug. Then I could plug the UPS into the outlet and the SO into the UPS. If the UPS goes down, bypass the UPS by plugging the SO into the outlet. The point... At work we have a lot of electronic equipment in closets in kitchens. We have heat issues there and they are somewhat climate controlled. I have the luck of my heater closet is off the two car garage. So my plan B is to mount a shelf for the UPS. Then instead of mounting the outlet next to the junction and the SO junction box, move it to the ceiling of the water closet. The outlets and face covers would isolate the air between the spaces.
Also, the new location gives me a chance to move the outlet for the garage door opener to the UPS. It would be nice to have a battery backup for the garage door, just not sure how much electrical noise it's motor would put out. Need more thought on that one.

NO doubt it would be sealed and removed before a home inspector was let into my house before a potential showing/sale. With that said, the air will be exhausted into the attic. The attic has a gable vent, an attic fan and probably 40 eave vents. I also have NEST protect carbon monoxide detectors which will notify me of any CO issues. I guess I'm confused where this CO would come from aside from a car backing into the garage for a short period of time. The garage entry door is about as sealed as my design is going to be (Probably less so as there is a slight gap (Covered by the door trim) between the rough opening of my door and the garage door (Have trim off all doors/windows currently). So any CO that would possibly exit my rack and find a crevice in the space between a header and conduit and creep down the wall and through some tiny opening would be minimal at best. Maybe I'm missing something here?

And there is about no animal that would dissuade me from this. In fact it may encourage it. I like animals 100x more than most people I meet.

Dave

 

[TT_Vert]

So the starting collar was the ticket! Had to reduce the diameter a hair but it fits like a glove. I later discovered that every device I am powering (Modem, switch, router, dvr and cameras all use 12V! The PC power supply can easily handle the current draw for all of them so I need no AC inverters! I'm using barrel jacks and again as luck would have it, each device uses the same barrel jacks I have on hand so into the PS they went. I'll just use a standard dongle to power each device right from the PC power supply. Bonus. Few more pics, pay no attention to the mocked up front cover, i'm still up in the air with how to handle it. And no comments on my free HF multi meter! It does the job great. I've gone through 3 of them on this new house lol. Good thing I stocked up. I should just bring my nice DVOM over but i'm too lazy.

 

[TT_Vert]

So after a month of some pretty hot temps (120+ in attic) my box has never gotten above 100 and has been working flawlessly. We'll see how it holds up but so far so good and well within temps for all devices up there.

Dave

 

[rharman]

< snip >
Years ago I was responsible for a large network. One branch location had their router (a Cisco 2502 router, which shows my age) in the uncooled attic, along with the Token Ring MAU and some other equipment.
< /snip >

Can't remember the last time I heard someone mention a MAU. That takes me back.

 

[Radix2]

The biggest problem for exhausting inside air into the attic is in the winter time. The warm moist air from the house condenses on the inside of the roof, making it wet, moldy and rots it. This is the reason that vapor barriers are used and ceilings need to be carefully sealed around penetrations.

Is your garage tied into the warm humid air of your house? Or is it just a unconditioned attached garage?

While you can push inside air in the house into the attic when it is hot, you need to make sure you do not do it (some kind of a cover?) when the temperature falls into the 50s and below and it becomes condensing for normal conditioned air.

 

[TT_Vert]

The biggest problem for exhausting inside air into the attic is in the winter time. The warm moist air from the house condenses on the inside of the roof, making it wet, moldy and rots it. This is the reason that vapor barriers are used and ceilings need to be carefully sealed around penetrations.

Is your garage tied into the warm humid air of your house? Or is it just a unconditioned attached garage?

While you can push inside air in the house into the attic when it is hot, you need to make sure you do not do it (some kind of a cover?) when the temperature falls into the 50s and below and it becomes condensing for normal conditioned air.

The garage is unconditioned. I do have a heater in this garage but I have no intention of using it. So the difference in temp between outside and garage isn't all that great. it is always going to be cooler than the attic air but not by a huge amount. I'll have to keep an eye on exhaust air temp vs. attic temp in winter but I'm not sure it will result in condensation. The other thing I could do is put another 8" duct at the bottom of the box to take all exhausted air back to garage.

Dave

 

[Radix2]

The garage is unconditioned. I do have a heater in this garage but I have no intention of using it. So the difference in temp between outside and garage isn't all that great. it is always going to be cooler than the attic air but not by a huge amount. I'll have to keep an eye on exhaust air temp vs. attic temp in winter but I'm not sure it will result in condensation. The other thing I could do is put another 8" duct at the bottom of the box to take all exhausted air back to garage.

Dave

The best thing would be to put in the return, then you have a solid plan for all seasons.