At CellarPro, we believe that creating a temperature-controlled wine cellar should be enjoyable—which is why it's important to "do your homework" upfront. By thoroughly researching cooling units and planning for your cellar's refrigeration, you can save yourself time, expense, and frustration in the long run.
Let us explain how you can avoid 5 common pitfalls we've seen customers make when selecting a cooling unit for their cellars.
Choosing a Unit: Where Do I Start?
The first thing you need to do is to determine the thermal load of your wine cellar: the amount of energy required to cool space to the desired temperature in an hour. Your thermal load, measured in BTUH, decides the capacity or size of the cooling unit you need.
Avoid Common Mistake #1: Don't select a cooling unit based solely on the size or volume of the wine cellar.
Just because a wine cellar is small doesn't necessarily mean that its thermal load will be small. For example, the thermal load of a 6'w x 2'd x 8'h wine cellar—with a volume of 96 cubic feet, 75°F ambient temperature, a desired cellar temperature of 55°F, and R19 insulation—is 681 BTUH.
Now let's imagine that 2 of the walls are uninsulated concrete below grade. In that case, the thermal load jumps to 969. What if the front and both side walls are glass? The thermal load jumps to 2957 BTUH (single-pane glass) or 1540 BTUH (double-pane glass)!
Avoid Common Mistake #2: Don't size the unit too small. Err on the side of caution and more cooling power.
Leave yourself some room for error by selecting a cooling unit that has a capacity above the cellar's thermal load. By doing so, you'll ensure that the cooling unit doesn't have to run non-stop to maintain your desired temperature inside your cellar.
If the cooling unit runs too much, it will have a shortened life span of use and the humidity inside your cellar will dip below recommended levels.
Planning for Exhaust and Intake
Once you know the thermal load of your cellar, and thus the required size of the cooling unit, you'll need to figure out to where the cooling unit will exhaust its hot air and from where it will pull its fresh air return.
Remember that the hot side (rear) of the cooling unit generates most of the noise, so you'll want to locate the rear of the unit where it won't interfere with your day-to-day life. This means that, with a through-the-wall installation, the cellar wall that holds the cooling unit should adjoin an area where noise isn't a concern. Otherwise, a split or ducted system will be a better solution, since you'll be able to place the loudest parts of the unit in a remote location.
Avoid Common Mistake #3: Don't let the hot air exhaust and fresh air intake mix.
If the cooling unit recycles and reuptakes its own hot air exhaust, this airflow will render the cooling unit useless.
Avoid Common Mistake #4: The cooling unit's fresh air return cannot come from the wine cellar.
It must come from outside the cellar.
Adjusting to External Environments
The conditions in the space around your cellar—the external or ambient environment—affect the type and size of cooling unit you need.
For instance, a very warm environment requires a more powerful unit to offset the higher thermal load. Some manufacturers' cooling units are limited in the amount of "drop" that can be produced inside the cellar. The maximum difference between external and internal temperatures that a unit can typically maintain is 30°.
A cooling unit would begin to have problems maintaining a stable 55° in your cellar if the ambient temperature rose above 85°.
Avoid Common Mistake #5: Make sure you know how a unit handles external temperatures.
Before purchasing a cooling unit, ask whether the cooling unit has a limit on the differential between the temperature inside the cellar and the temperature outside the cellar.
Some cooling units have a 30° differential and others have a differential as large as 55°. In other words, if temperatures rise to 95°F outside the cellar, the coldest temperature inside the cellar would be 65° if the cooling unit had a 30° differential.
There's a science to selecting the right cooling unit for your project. Although the steps may seem difficult at first, you need mostly easily-obtainable information. Remember, there is a range of units available, designed to refrigerate cellars with diverse cooling needs.
Plus, you don't have to think through the intricacies of choosing a unit on your own. At CellarPro, we're more than happy to help you size a cooling unit for your wine cellar. In addition to offering free thermal load calculations, our support team will provide answers to any questions you may have about cellar refrigeration.
Make sure to do your research before buying and then sit back and relax while your cooling unit hums quietly inside your perfectly-chilled wine cellar.