Seeking wisdom - Garage server rack cooling

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eptesicus

Active Member
Jun 25, 2017
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I'm putting a server rack in my garage that'll have about 2000W, with a potential max of 3000W load depending on how little sleep I get and more insane I become. I'm in Middle Tennessee and I also use my garage for garage-things, so having an AC in the garage to flood the entire garage with cooled air is not ideal, because I open the garage door often. I also have to be mindful of dust. I once had a rack in the garage, but I didn't seal it well and heat and dust were my enemy, so I downsized to a smaller rack indoors, but where the rack is there, I can't keep temps where they need to be, so back to the garage it goes, but I'm going to be actively cooling it.

I'm planning on getting a 12k+ BTU evaporative dual-vent portable AC unit (window unit or a minisplit are not an option), putting 1" insulating foam in the rack and completely sealing it, or building some sort of movable barrier to isolate the equipment in the corner. I'm really not sure how to go about this. With the dual-vent AC unit, I'll need 2 ducts to run outside the house, one for intake, and one for exhaust. My thought was that I could pipe the cooled air from the AC unit into the rack, then have an exhaust fan at the back of the rack, joining that exhaust with the AC unit's exhaust to vent out of the garage... or the AC's exhaust goes outside, but the back of the rack exhausts into the garage.

This is not our forever home, and I don't want to properly build a closet in the garage. Space is also a premium, so I was thinking that completely sealing the rack cabinet, having the portable AC unit next to the rack, and ducting it into the front door, would be the most space-saving option. Having a movable barrier could also be good as I'd be able to insulate it and help kill noise.

What are the appropriate routes to take here? I have to move my equipement from inside the house to the rack in the garage in a couple weeks, as we had water damage and the contractors will be starting demo of all the first floor flooring soon. I need to move the equipment to the garage before then.

Also, aside from the Tripp Lite SRCOOL unit, is there a portable AC unit you'd recommend? Especially if it's 'smart' in some way that I may be able to control and monitor it through Home Assistant?

Below is a crude drawing I thought up too with a hinged movable 2-panel wall that I could maybe latch to both of the walls in that corner of the garage. There's also a work bench and cabinets to the left of where that wall would be, and a big safe against the right wall. I built a storage soffit on that right wall that's just low enough where the rack can't go under it, but it fits in that corner. I'll need a way to access the front and back of the rack... The electrical panel is also right where the AC is, so I need to be able to get to that as well.
signal-2023-04-19-203600_002.jpeg
 

eptesicus

Active Member
Jun 25, 2017
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If you have some space in your rack you can think about something like that: Horizontal Air-Cooled Rack-Mounted Air Conditioners
We do use roof mounted coolers from Rital, available with IOT interface
Not as cheap as a monoblock standing aside, but much more efficient and no hassle.
Thanks, the expense is what's killing something like that for me. I've checked ebay, and don't see anything used at a price-point that would allow for some room to have an HVAC out to ensure it's 100% where it needs to be. I need to stay under $700 for the AC unit. I definitely can't exceed $1000 for it right now unfortunately. Tripp Lite has a rackmount 7k BTU unit, but I was worried about it having enough capability. I'm not gonna run it at 72F, but figured maybe 78 or 80F, depending on how thermals look on the systems on a hot day. They also have a standing 12k unit, but I've read mixed reviews on reliability.

So, I started looking at the more consumer units, especially the dual-vent ones, as I know they're far more efficient than regular ones.
 

T_Minus

Build. Break. Fix. Repeat
Feb 15, 2015
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You should get an Inverter based AC unit. I would go with a mini-split, around $1200 for the MrCOOL DIY 12k BTU.
If that's too much $ then you could go with one of these: https://www.amazon.com/Midea-Inverter-Conditioner-Flexibility-Installation/dp/B08677DCKN/ They're rated really good, and not 12K (but they do make large ones than this), and you could install it on your wall so the heat goes into the garage and up and out vents, and cool air into the mini-server room.

I have used the old style floor standing units and window units and they do not cool nearly as well as inverter mini-split, second best would be window inverter unit.
 
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eptesicus

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Mini-split is definitely what way to go, I just didn't want something so permanent that I likely can't remove and put in the new place when we sell the house, not to mention the cost.

However, I may just have to bite the bullet on that, or get this Vertiv VRC200KIT 12k BTU rackmount split system. - Vertiv | VRC200KIT | 6U Indoor Unit Single Phase 120V 60Hz Split Cooling System | eBay - It's just the indoor unit and doesn't include the outdoor condensor... Bummer.

The Tripp Lite SRCOOL7KRM can be had new for about $1k, but I worry about sizing. Let's say I have 2500W of continuous power running in this rack, I just need cool enough air in the intake to ensure the cool air is at a cool enough temperature. I'm not trying to bring the exhausted air down to a comfortable temperature, I just need to quickly draw that out. So, do I really need a 12k BTU AC to pipe into the rack? I may need to reach out to r/HVACadvice.
 
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eptesicus

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Jun 25, 2017
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Here's another crude drawing of my garage and plan...

The problem with a mini-split, is that I'd need to install the interior unit on the exterior wall on the left, when would need to have some sort of insulated ducting run over to the far right wall to route the cooled air to the rack. I had considered just moving the rack to the left side, but am concerned, as it'd need to be pretty much right in front of the water heater and main shut-off valve.

There's ways of mounting the indoor unit of the mini-split on an interior wall, but it further complicates the install, and I'm not sure what will be impacted from this.

signal-2023-04-20-141302.jpeg
 

CyklonDX

Well-Known Member
Nov 8, 2022
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I would ask following:
have any ventilation vents in your garage?
are you hoping for high utilization (a lot of heat being produced?)


/ for high utilization

If you do not have a vent, make one... and use vent hose
Use it for AC exhaust, and exhaust from servers, potentially add a fan to that vent hose (or aquire one of those https://www.amazon.com/AC-Infinity-CLOUDLINE-S6-Controller/dp/B07FPFVZTZ)

Next step you should isolate intake, and out of your servers... ensure no air is going sideways - and can only pass through your servers.
(use those or similar to block any air going throw your rack.)


This is ideal small "room" isolated, AC server rack room.
1682050784573.png
This way your AC won't have to work extra to cool down the heat generated by the servers; and you will be able to slow down the fans - and have smaller bill on power.

You should leave enough space for yourself to get into back, and front. (but if you use those insulation roll or something you should be able to open whole wall or something.
(just like those growth systems)
1682050999277.png
but you will be aiming to create something bigger.
 
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eptesicus

Active Member
Jun 25, 2017
151
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28
35
I would ask following:
have any ventilation vents in your garage?
are you hoping for high utilization (a lot of heat being produced?)


/ for high utilization

If you do not have a vent, make one... and use vent hose
Use it for AC exhaust, and exhaust from servers, potentially add a fan to that vent hose (or aquire one of those https://www.amazon.com/AC-Infinity-CLOUDLINE-S6-Controller/dp/B07FPFVZTZ)

Next step you should isolate intake, and out of your servers... ensure no air is going sideways - and can only pass through your servers.
(use those or similar to block any air going throw your rack.)


This is ideal small "room" isolated, AC server rack room.
View attachment 28514
This way your AC won't have to work extra to cool down the heat generated by the servers; and you will be able to slow down the fans - and have smaller bill on power.

You should leave enough space for yourself to get into back, and front. (but if you use those insulation roll or something you should be able to open whole wall or something.
(just like those growth systems)
View attachment 28515
but you will be aiming to create something bigger.
Thanks! I actually have plenty of flexible ducting and 2x AC Infinity T6 inline fans for my current setup. I plan to use at least one of them for exhausting the rack into the garage space or ducting it outside.

I actually pulled the trigger on a mini-split after discussing it all with the wife and getting some other input on it. The efficiency of it will likely mean that, with 2x home AC units I have currently not having to fight anymore to cool and replace the heat from the old rack inside the house, it may not cost me much at all to run this dedicated unit for the rack in the garage.