My local HVAC guy is recommending we install a Daikin mini-split 1-ton system FTK12AXVJU for a new cellar. Would anyone recommend going this route, or instead playing it safe with a unit made specifically for wine?
A few options we are considering:
Daikin mini-split @ $3800 (installed)… I like the price of Daikin, and that my HVAC guy will be responsible for servicing it… but I am worried about temp control/fluctuations, humidity control and in general using a unit that may not be “fit for purpose.”
Wine Guardian DS050 split @ $8500 (installed) …have heard great things about WG!
Wine Guardian DS050 self-contained / ducted @ $5500 (installed) …have heard great things about WG, but maybe we do not need a split system?
Cellar is 4x10 ft + 7.5ft ceilings with insulated glass display, spray foam on remaining 3 walls and ceiling. Installed in a basement in Georgia
Would love this community’s input, there’s a lot of conflicting info out there…
+1 for CoolBot. I built a room in my garage insulated with foam board and fiberglass insulation and a window LG unit above the door. Works great. Can’t really comment on humidity but steady temperature I think is far more important to long-term ageing than humidity, especially consieration the damage you can do if humidity is too high. If your temps are higher with high humidity, an AC unit will dehumidify naturally.
One word of caution, newer window units are designed to self cool the unit itself by splashing the condensation from the cooling fins back onto the fins (the fan blade acts as “paddle” dipping into the condensation tray at the bottom). On the outside of a house this would be fine but if you have it anywhere inside, it can splash the water on your interior walls. I have only experienced this when the door has been left open for too long and the unit needs to run for a while (more than 20 minutes at a time). Normally it runs for about a minute or two before shutting down. If you are going with mini-split then no worries, just make sure your mini-split is compatible with CoolBot.
I’m in the middle of a cellar build right now too, and also looking at Wine Guardian. For those options, have you carefully calculated how big of a unit you need? My cellar is about 8x10x7 (so bigger than yours) and that’s a significantly larger unit than I’m looking at (though, I don’t have any glass, which definitely makes a difference). I can’t speak to the Daikin route, but definitely make sure you’re comparing against the right specs for each option.
Someone back in time told me that the more conventional household HVAC systems are designed for keeping temps between 65 and 75 roughly in terms of engineering. So how much the blower runs, coolant, etc… Obviously the R factor of the surrounding structure plays heavily in to that. I’m sure that there could be conflicting accounts but it holds water to me. Daiken seems to cater to cooling single residential rooms based on their brochure, not wine cellars for 55 - 58 degrees depending on your tastes. That could have runs on power and overuse of the mechanical parts meaning it could die prematurely.
That said, if you can, I like split ducted systems personally. I don’t have practical experience with Wine Guardian however I’ll assume it sits in the same ballpark, specialized and optimized to purpose. I have a WhisperCool platinum split ducted that just chugs along with light maintenance. You hear nothing mechanical ever. I structured the supply and returns for the room to not hinder aesthetics, and it was a worthwhile investment.
I wish you luck and just make sure you are happy with the investment and weigh the risks. Upfront costs can be scary. Scarier is when something goes down because it was not designed for purpose and your wine is at risk mid-summer waiting for someone to show up and maybe fix it for a cost that negates upfront savings. I’ve heard horror stories.
The main problem with residential units is their humidity management. They want to keep humidity between 40 and 50% which is too low for a cellar.
The dedicated wine units keep more humidity in the cellar through a variety of methods.
The wine units are usually sized for smaller spaces as well. Residential units might not get enough heat across the coils to prevent freeze up because they are cooling too well.
4x10 is a very small space, so you do need to be sure that the unit isn’t too big. If it is too big, as others have said, you may have problems getting enough air pushed through to dehumidify.
The prices seem high for 40 sq. ft. I installed Mitsubishi split units in bedrooms that are about 400 sq. ft each, and each unit ran about $3,250 installed after rebates.
I would wonder, too, about a unit meant for habitation temps and humidity – and about and HVAC guy’s knowledge of systems to maintain temp control below 60.
My split units keep the temp in a very narrow range. I love them – quiet, super efficient, and no noticeable temp fluctuation. In terms of fluctuation, they would be fine for wine.
Moreover, while it’s “common wisdom” the fluctuations matter, there is zero research on that, as has been discussed in other threads. Same thing with the sacred temp of 55F. I’d worry far less about temp variations and the actual temp, if under the low 60s, than I would about high humidity and mold.
Maybe split the difference and buy a cool room drop in refrigeration unit? My cellar is a walk in cool room and that’s what I use for cooling. They’re designed to run at much lower temps than what is required for wine cooling so using them for cellaring doesn’t cause any issues from a long term reliability perspective. My humidity is good (~70-80%) and I’ve got the thing hooked up to a temperature controller so it only runs when required. Also they’re much less expensive when compared to wine specific units. Finally, given they’re ubiquitous in restaurants and other businesses that require cold storage you can find spare parts and people to work on them very easily when compared to wine specific units.
I have done exactly this and works great in NC for over 6 years. You just need a Coolbot to get the temps down. I am not a HVAC pro but not sure what wine unit does humidity wise any differently unless it is plumbed. I’ve had cellars in CO where I added humidity and in NC where I remove it mainly in the summer. I try to keep it 60/70% which is higher than most. I’ve been super happy with the setup as quiet, reliable, and most anyone can service it.
I use a mini-split system in combination with the CoolBot here in Atlanta. The system works great for my cellar. Humidity in this region is not an issue in a cellar that is below grade. My cellar actually needs more dehumidification vs adding humidity. The cautions noted previously on not “over-sizing” the unit are solid, especially in such a small space as a 4x10. Beyond that, I’d have no concerns about using this combo technology in the application in Atlanta. My system has been running now for 3+ years with minimal maintenance (cleaning, refrigerant).
Did the AC ppl install the coolbot for those of you using them? Also what would people advise adding to a large passive cellar for additional cooling? I have a passive cellar in a basement in wi where the temps are usually low 60s but thought if I could add a small mini split with coolbot it would work but the room is pretty large.
For me yes, the HVAC crew did the coolbot install. It did take a second try to get it dialed in. And yes adding active cooling to a passive cellar is the same as any cellar. Just less load and you have the same design issues. Insulation, vapor barrier, and how best to run the cooling infrastructure.
Right, except this “cellar” has none of those things. It’s just a room in a basement that I store some a couple hundred cases of wine that I don’t really feel like moving to my main cellar which is hundreds of miles away. It’s probably fine at the temperature it’s at, but given that it’s relatively long term storage, I figured adding an inexpensive mini-split or wall unit with coolbot would be a good option that could cool the room from its current temperature range of 58-62 to 55.
The extra thermal load can be compensated for with unit sizing. But depending on humidity where you live I’d worry about condensation and then possibly mold once you made that room actively cold. I’ve seen active cellars in humid climes without the proper insulation/vapor barrier and it ended up rotting wood in the floor. If I was in CO (super dry) I would not really worry but in NC I would not actively cool w.o. those measures in place. A commercial refrigeration person can advise. I would not trust a regular HVAC dud who rarely does walk in fridges which is basically what a wine cellar is.
You don’t even need a CoolBot. I’ve been running for 11 months with a $550 9000 BTU mini split that an A/C guy installed on the side for $400 in my 5’ by 9’ cellar with 10’ high ceiling. I changed the thermistor and now I just set the temp to 71 degrees but the room is cooled to about 55 degrees. I have the fan run continuously and the unit cycles anywhere from once an hour to once every two hours – this was for a new house build.
I’m in San Diego area and I let the contractor and insulation contractor talk me out of a vapor barrier (they put one up initially, but put it on cellar side which I told them was all wrong, and in the discussion I got talked out of it, partially because trying to do vapor barrier on the attic side was an issue in terms of exactly how do you do that), so I did find that I had to add a small dehumidifier but that has worked out ok too – I’m able to keep humidity between 52% to 60% which is where I want it to be.
Bottom line, it works great, and a temp sensor taped to the outside of a bottle shows the temp on the outside stays in a 0.8 degree range for AC on to AC off cycles while a temp sensor of air at the ceiling of the cellar ranges about 1.8 degrees between AC on/off.
I’ve got a bag of 6.8K thermistors (most mini splits use a 10K thermistor, you snip two wires, change the thermistor and the temps are now remapped so the AC will cool lower, and the little bit lower, coils freezing is not an issue, for sure not once room is at cellar temp – if it’s an issue for you, bring the temp down over a day or two by lowing the set temp a degree at a time) bought for $12 on eBay – happy to send more details if anyone wishes. At some point, I’ll do a whole writeup with pictures – but I’ve been saying that since I put the cellar in too, lol Mini Split Thermister Mapping - 10K to 6.8K.pdf (509 KB)
I use a wine guardian with matching humidifier. It works great. I have it circulate air constantly. The cooler comes on occasionally. It’s pretty quiet. Quality seems pretty good. Mine both heats and cools.