How to Size a Wine Cellar Cooling System
Sizing a wine cellar cooling unit takes 15 minutes if you have the cellar dimensions. This is the calculation method, including the adjustments for construction quality and ambient conditions.
What you need before starting
- Cellar interior dimensions (length, width, ceiling height in feet)
- Exhaust-side ambient temperature (worst-case summer reading of the room the unit vents into)
- Wall insulation R-value (R-13, R-19, R-30, or R-38)
- Whether the cellar has glass walls, missing vapor barrier, or a standard (not insulated) door
Step 1: Measure cellar dimensions
Length × width × ceiling height = cubic feet. Example: 5 ft × 7 ft × 8 ft = 280 cubic feet.
Step 2: Determine exhaust ambient
The temperature of the room the cooling unit will vent into, at the worst-case summer condition. Common values:
- Conditioned interior spaces: 75°F
- Basement utility rooms: 80-85°F
- Attics or garages: 85-95°F
Step 3: Calculate delta T
Exhaust ambient minus cellar setpoint (55°F). Example: 80°F exhaust - 55°F cellar = 25°F delta T.
Step 4: Apply the insulation factor
| Wall R-value | Heat-loss factor |
|---|---|
| R-13 (minimum) | 0.080 |
| R-19 (standard) | 0.055 |
| R-30 (high-perf) | 0.035 |
| R-38 (cold-climate) | 0.025 |
Step 5: Calculate base BTU load
Formula: cubic feet × delta T × insulation factor × 18
Example: 280 cu ft × 25 delta T × 0.055 (R-19) × 18 = 6,930 BTU/hr base load.
Step 6: Add adjustments
- Glass wall: multiply by 1.65
- Missing vapor barrier: multiply by 1.15
- Standard uninsulated door: add 250 BTU
- Above-grade exposure: multiply by 1.1-1.2
Step 7: Add safety margin
Multiply by 1.20 (20% margin) to cover ambient variability, door cycling, and initial loading conditions.
Step 8: Match to a cooling unit
Pick a unit with BTU output at your exhaust ambient that matches the calculated load. See our comparison hub or use the interactive calculator.
Sizing chart shortcut
For R-19 walls, 75-80°F ambient, no special conditions, with safety margin already added:
| Cellar size | BTU/hr needed | Typical unit fit |
|---|---|---|
| 100 cu ft | ~1,500 BTU/hr | Breezaire WKL 1060 or WhisperKool Platinum 1600 |
| 200 cu ft | ~2,500 BTU/hr | Breezaire WKL 2200 or WhisperKool Platinum 1600 |
| 400 cu ft | ~3,500 BTU/hr | Breezaire WKL 3000 or WhisperKool Platinum 4000 |
| 650 cu ft | ~4,500 BTU/hr | Breezaire WKL 4000 or WhisperKool Platinum 4000 |
| 1,000 cu ft | ~5,500 BTU/hr | Breezaire WKL 6000 |
| 1,500 cu ft | ~6,500 BTU/hr | Breezaire WKL 8000 or WhisperKool Platinum 8000 |
| 2,000+ cu ft | 7,000+ BTU/hr | WhisperKool SC PRO ducted or split system |
For sizing help with edge cases (high ambient, glass walls, large cellars, commercial), use our interactive calculator or call 855-625-9463.