If you don’t plan on building a traditional wine cellar you have two choices for long-term wine storage: Wine Storage Cabinets and Credenzas also known as Forced-Air systems and Electric Wine Cellars or Cold-Wall systems.
You can separate a wine storage cabinet into two parts, the wooden wine cabinet and the cooling system. A forced-air cooling unit is self-contained and fits into a hole in the wine cabinet like an air-conditioner. An electric wine cellar (cold-wall system) is fully integrated and functions like a refrigerator (but should not be confused with a wine refrigerator which is a short-term wine storage device).
Examples of wine storage cabinets and credenzas are Vintage Keeper (now WineKoolr), Vinotemp, Vinotheque and Le Cache. Electric wine cellars are Eurocave, Sub-Zero and Transtherm (a cheaper version made by Eurocave).
Note: The forced-air cooling system for Vintage Keeper is Koolspace, Vinotemp has the Winemate, Vinotheque has Whisperkool and Le Cache has Breezaire.
Performance Inside vs. Outside
People rarely think beyond aesthetics or available storage space when they put their wine storage cabinet in a garage or other non-temperature-controlled area. For example, Koolspace (aka Vintage Keeper, aka WineKoolR), which is probably the cheapest wine cabinet available, is widely believed to be the perfect garage wine storage system because it’s not particularly attractive and loud. However, the Koolspace owner’s manual states:
Never locate your wine cellar outdoors or in an area with extremes of temperature and humidity. (Not in) Garages, attics, unfinished basements, laundry rooms, breezeways, closets or any unventilated room. In other words these units must be installed in air-conditioned environments which do not “trap” the warm air being exhausted. Temperatures in the surrounding area must not exceed 80°F (25°C) with humidity levels not to exceed 70% R.H. (Relative Humidity).
Wine storage cabinets in warm environments need heavy-duty cooling and additional insulation, aesthetics are the least of your worries. Thermal-paned, insulated glass doors are fine for an air-conditioned living room. They are not sufficient for uncontrolled environments.
Wine storage cabinets made by Vinotemp, Vinotheque and Le Cache have optional heavy-duty cooling systems and can be customized with additional insulation and solid doors. However, their forced-air cooling systems (just like Koolspace) are limited to cooling 25 – 30°F below ambient temperature. So, in order to maintain the ideal wine storage temperature of 55°F, the wine cabinet cannot vent into a room that exceeds 80 – 85°F.
Warm temperatures aren’t your only problem, if you live in an area that experiences temperatures below freezing, you risk damaging your wine (e.g. broken bottles or dislodged corks) because forced-air systems don’t provide heat.
The cold-wall systems of Eurocave and Transtherm on the other hand have an ambient temperature range of 32 – 95°F, as well as optional solid doors. Not only are they capable of cooling 40°F below ambient, unlike forced-air systems they heat as well. So, if you’re looking to locate your wine collection in an area that is less than ideal, cold-wall systems are your best bet.
Minimizing Temperature Fluctuations
Maintaining a constant wine temperature is the main concern of wine storage. The rule of thumb is no more than a 1 – 3°F variation in AIR temperature. Using this measure, all of the above systems are acceptable because they all maintain AIR temperatures within +/- 3°F. While this may seem excessive, a +/- 2°F variation in AIR temperature is equivalent to a 0.5°F change in WINE temperature (because the wine bottle provides insulation and air temperature changes much faster than liquid temperature).
Electric Wine Cellars
Most of the Eurocaves maintain air temperature within +/- 1°F of set temperature as does Sub-Zero. Transtherm maintains air temperatures within +/- 3°F. However, the Eurocave Performance series corrects air temperature fluctuations of as little as 0.1°F, as close to constant as you can get.
Wine Storage Cabinets
Koolspace maintains air temperatures within +/- 3°F, and Le Cache +/- 2°F. But Vinotheque uses a system whose numbers can be misleading. Both Vinotheque’s Vintronic I (analog) and III (digital) bottle-probe thermostats maintain WINE temperature within +/- 0.5°F of set temperature. This number seems comparable to Eurocave’s Performance Series, but as explained above a +/- 0.5°F variation in WINE temperature is equivalent to a +/- 2°F variation in AIR temperature, so it is in fact the same as Le Cache and not even close to the Eurocave Performance Series.
Ideally, electric wine cellars and wine storage cabinets should maintain a relative humidity of 70%. Relative humidity is a measure of the amount of water in the air compared to the amount of water the air can hold. Because warmer air can hold more water, relative humidity varies with temperature.
The forced-air cooling system in wine storage cabinets “control” relative humidity by using this natural law. For example, if the temperature in the ambient environment is 72°F and the relative humidity is 30%, then the relative humidity inside the wine cabinet will rise to 60% when the temperature cools down to 55°F. This works as long as the water in the air is within certain parameters.
Since the forced-air cooling system does not create humidity, dry climates can be a problem. If you live in a very dry climate, you can increase the humidity inside the cabinet by placing a wet sponge in a shallow container at the bottom of the cabinet.
Areas with high humidity can also be a problem. If the cooling unit is originally turned on when conditions are at 75°F and 50% relative humidity, the humidity will reach 100% at 55°F. The cooling unit will be overworked and the excess water could overflow from the unit, making a mess. This illustrates once again why forced-air cooling systems should be used in air-conditioned environments (which dehumidify the air).
Forced-air humidity systems can be considered passive compared to cold-wall humidity systems that actively recycle, distribute and monitor humidity. Sub-Zero uses dual evaporators, one for each storage zone, that maintain steady, moderate humidity. Transtherm heats the condensed water that drains into the drain pan at the bottom of the unit and distributes the humidity through natural convection (called a thermal pump process). It also monitors the relative humidity in the cabinet.
Eurocave has a sophisticated humidity system that ensures a constant humidity level. The natural humidity in the air condenses on the cabinet’s SRA (Stone Relief Aluminium) walls, where the texture captures the droplets and distributes them evenly. The humidity is then regulated by a cartridge of clay pellets.
Meanwhile, a sensor measures the humidity level with precision. Eurocave electric wine cellars are the only units to have an automatic display and humidity level warning system. They also have clay cassettes at the bottom of the cabinet where you can add water if you have a low humidity alert.
Noise and Vibration
Forced-air cooling systems by their nature create more noise and vibrations than an advanced cold wall system. A forced-air cooling unit is like an air-conditioner in function (it blows air into the cabinet), while a cold-wall cooling system is like a refrigerator. Realizing that most people don’t want a noisy forced-air cooling system in their living room, Vinotheque developed the QT cooling system that uses natural convection, significantly reducing noise.
A forced-air cooling unit is self-contained and fits into a hole in the wine cabinet. This direct contact with the cabinet causes vibration that’s absorbed by the cabinet and ultimately the wine. On the other-hand, cold-wall system Sub-Zero uses a quiet compressor that lets wine rest undisturbed. Transtherm uses slow and balanced compressors, and disassociates them from the cabinet’s body, eliminating all residual vibrations.
Eurocave’s compressor unit is detached from the cabinet, and rests on 4 high performance “Silent Blocks”, stopping any vibration from entering the cabinet. In addition, there are 4 rubber shock absorbers located on each bottle shelf, keeping any residual vibration to a minimum.
Wine breathes through the cork. Without aeration, a wine’s taste would be distorted and mold would eventually develop. All long-term wine storage systems provide fresh air for the wine cellar or cabinet. But, Eurocave takes it one step further. They provide a charcoal filter that’s used to purify incoming air and stop unpleasant smells from entering the wine cellar.
Ventilation is very important when considering a wine storage system’s location. The compressor emits heat, which must be removed from the unit. If the cabinet is located in a restricted area where ventilation is not available, the ambient temperature of the room will increase and prevent the unit from cooling adequately.
Be sure to find a location with good ventilation. In the case of Vinotheque, the rear of the unit should be placed approximately 2 inches away from the corresponding wall. In addition, there should be approximately 12 inches of clearance above the top of the unit and 6 inches on each side. Front venting that allows the unit to be built-in (surrounded on the back and sides) is available as an option.
Most of Vinotemp’s units are designed with back exhaust (top and side venting is an option), therefore you need a minimum of 4 to 6 inches on back, 12 inches on sides, and 6 to 12 inches above for proper ventilation. Koolspace needs 3 inches of clearance from a wall.
Le Cache is known for its “SB/0 Technology” that has zero set back. But, it does require adequate ventilation on the top of the unit (13 to 18 inches). Sub-Zero and Eurocave (Compact series) have models with front venting, specifically designed to be built-in.
Dual-Zone vs. Single-Zone
For the purposes of long-term wine storage, a dual-zone wine cabinet is not necessary. Both red and white wines can be stored at 55°F. However, dual-zone wine cabinets are convenient, you can store wine at 55°F on one side and chill wine for serving on the other. Of course, you can always chill your wine in a regular refrigerator, or with ice. You can even buy a wine refrigerator to chill your wine to optimal serving temperatures. But a dual-zone wine cabinet makes things easier and saves space.
All of Sub-Zero’s wine cabinets are dual-zone except its smallest unit. Vinotheque has a dual-zone option for its two largest models. Vinotemp has one 400-bottle dual-zone model. Le Cache doesn’t have a dual-zone option. Eurocave and Transtherm have dual-zone and triple-zone models of all sizes. A triple-zone model has a large long-term storage area, a smaller chilling zone and an area to warm red wines to room temperature.
Total vs. Racked Bottle Capacity
Total bottle capacity is very different from racked bottle capacity. Total bottle capacity takes into account both bulk storage capacity (bottles stacked on top of each other) and
individually racked bottles. You want as many individually racked bottles as possible because when bottles rest on bottles, they can break or get scratched, or the labels can smudge or tear. Bottles in bulk storage are also much harder to access than individually racked bottles.
Unfortunately, individual racking takes up more space, so if you’re trying to fit a large number of bottles into a small area, bulk storage is necessary. This is the case with Eurocave and Transtherm. One of their selling points is the ability to fit a comparable amount of bottles as their competitors into a smaller space, but of course this requires a lot of bulk storage. You can get all sliding racks with Eurocave (or a mix), but this significantly decreases total capacity.
Large Bottles & Racking Options
Sub-Zero, Eurocave and Transtherm base their bottle capacity on 750ml Bordeaux bottles. Although racking designed for wide Burgundy and Champagne bottles is available, storage capacity will be reduced. In comparison, Le Cache and Vinotemp use universal racking that’s designed to fit all bottles, so bottle type doesn’t affect stated bottle capacity.
Vinotheque gives you three racking choices: traditional, progressive or universal. Bottle capacity depends on racking choice. Koolspace has flat racking that can accomodate all bottle sizes. Large bottles will reduce storage capacity.
Wood vs. Metal Racking
Koolspace has metal racks, as does Sub-Zero (with wood facings). The less expensive Vinotheque models have metal racks, the high-end models are all wood. Except for the Sonoma series, all of Vinotemp’s cabinets are a combination of wood and metal. The Sonoma series has all redwood racking.
Le Cache has all-wood racking, so does Transtherm. Eurocave’s fixed racks are made of tropical hardwood, its sliding racks are wood and metal.
Note: Vinotheque, Le Cache and Koolspace have fixed racks. Most of Vinotemp’s models have fixed racks, one or two models have all sliding racks. Sub-Zero has all sliding racks. With Eurocave and Transtherm you have a combination of the two.
Metal racks inside wine cabinets can scratch bottles and tear labels, and sometimes they can bend out of shape under the weight of racked bottles. However, wood racking takes up more space, which reduces total bottle capacity.
The wood / metal combination seems like a perfect compromise but these racks often suffer from the same problems as metal racks (i.e. the tendency to bend under the weight of bottles). The Grape-Nutz website has an interesting anecdote on the subject. The wine cabinet in question is the Vinotemp 600E (Vinotemp’s Economy series).
Electric Wine Cellars like Eurocave and Sub-Zero are superior to Wine Storage Cabinets like Vinotheque and Le Cache in all areas except wine racks. Individual wood racking protects the wine bottle better although it requires more storage space. Nevertheless, if you’re in the market for a long-term wine storage system, electric wine cellars and Eurocave in particular are a no-brainer.