The ideal temperature and humidity of any wine cellar would do well to mimic the natural conditions of France's legendary wine caves, which are acknowledged to be close to perfect.
Keeping the rest of the world's cellars at the same 55-57 degrees Fahrenheit (14 degrees C) and with an average of 60% relative humidity generally requires some form of dedicated wine cooling system. To properly control the cellar temperature and humidity, the system should take into account and manage not only the cellar's temperature but also the vagaries of the climate in which you live. It is hot/dry? Hot/humid? Cold/dry? Cold/humid? Will your system also be required to supply heating to maintain the correct winter temperature? These are all important considerations when building or retrofitting your wine cellar.
Wine
Understanding Temperature
55- 57 degrees F (14 degrees C) is considered to be the ideal temperature for storing and properly aging wine. If the temperature consistently fluctuates up or down several degrees, your wines will be compromised and may age prematurely.
- Some cooling units are controlled using an in-bottle liquid temperature device, which signals the unit to adjust when it senses a change of 2 to 4 degrees of temperature in the liquid. Unfortunately, by the time the wine inside the insulated bottle reacts to the fluctuation, the air in the cellar has already shifted many more critical degrees.
- A wall-mounted thermostat with a range of + or - 1 degree F is ideal.
- Cellars subject to ambient temperatures below 55 degrees F should be protected by a heating coil. Without the ability to heat, a cooling unit can do nothing if the temperature in the cellar falls below the control set-point. The best system is one where the heating is integrated into the cooling unit and works on the same thermostat.
How to Resolve the Temperature Problem
- In all cases, quality should be a primary consideration. A cheap initial price will soon be forgotten if the wine cellar cooling unit fails and stresses your wine.
- Wine cellar units should be rated close to the intended operating temperatures and humidity. This means around 55 degrees F and 60% relative humidity. Be sure the unit you are buying is rated for wine cellar use, not household use.
- Because there are many variables other than the number of bottles or the cubic footage of the cellar to consider before selecting the type and size of a cooler, it is best if the calculation is done by a professional using a load calculation program. These variables might include frequency of door openings, lighting intensity, room insulation, doors and windows, frequency of case turnovers, etc.
Why is Humidity Important?
Humidity is a critical feature often overlooked in wine cellar design. 50% - 70% is recognized as adequate, with 60% the ideal.
- When the humidity is higher than 70%, it will likely cause mold and degradation of the labels and glue.
- When the humidity is below 50%, corks will begin to dry out resulting in loss of liquid in the bottles and possible degradation of the wine.
How to Resolve the Humidity
- First step should be the installation of a vapor barrier around the entire room. A minimum of 4 mil plastic is recommended with seams overlapped and taped. The vapor barrier is installed on the outside (or warm side) of the cellar insulation. This is to prevent condensation from forming on the vapor barrier, potentially causing mold.
- A cooling unit alone cannot add moisture or humidify cellar air. It needs a humidifier to do so. The best option is a humidifier integrated into a cooling unit so it operates and distributes the moisture evenly in the re-circulating air. However, a free-standing humidifier can also be installed in conjunction with a cooling unit as long as this is controlled by a high-quality wall-mounted thermostat.
Wine Guardian® wine cellar cooling units are commercial grade equipment for upscale residential and professional wine cellars and storage facilities. Wine Guardian coolers are high-performance and installation-friendly, with many features and options not found in any other systems:
• Completely self-contained, requiring no external piping
• Can be installed through-wall, ducted remote, or any combination
• Built-in powerful, motorized impeller fans for external ducting
• Pre-wired, wall mount thermostat for flexibility of location and proper control of temperature and humidity
• Built-in, cleanable filters on both evaporator and condenser coils to keep free of dust and maintain optimum operating conditions
• Corrosion-resistant cabinets of powder-coated aluminum for lasting durability
• Options include: humidifier for dry locations; electric heating coil for cold climates; low ambient protection for mounting in cold areas such as a garage or outside shed
Wine Guardian wine cellar cooling equipment is distributed internationally. For more information: http://www.wineguardian.com