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BTUH Adjustment Factor Per Square Foot of Glass

When using glass in a wine cellar, the heat loss through the glass must be considered when sizing the cooling unit.


Cellar Temperature
Type of Glass
Single-PaneDouble-Pane

Cellar Insulation

Ambient Temp

55°F Interior

60°F Interior

55°F Interior

60°F Interior

R12

65°F12.206.105.002.50
70°F18.3112.207.515.00
75°F24.4118.3110.017.51
80°F30.5124.4112.5110.01
85°F36.6130.5115.0112.51
90°F42.7136.6117.5115.01

R19

65°F12.606.305.402.70
70°F18.9012.608.105.40
75°F25.2018.9010.808.10
80°F31.5025.2013.5010.80
85°F37.8031.5016.2013.50
90°F44.1037.8018.9016.20

R30

65°F12.846.425.642.82
70°F19.2612.848.465.64
75°F25.6819.2611.288.46
80°F32.1025.6814.1011.28
85°F38.5232.1016.9214.10
90°F51.3638.5219.7416.92

This table calculates heat loss using: 1) Ambient temperature where the glass is located 2) Desired temperature inside the wine cellar 3) R-Value of the cellar's insulation. To use this table, start by calculating the standard thermal load (in BTUH) using our other charts, the size of the cellar, the R-Value of insulation used in cellar construction, the ambient temperature outside the cellar, and the desired temperature inside the cellar. Multiply the square feet of glass times the adjustment factor in the above table, adding the resulting BTUH to the standard thermal load calculation.

If you have any questions, please don't hesitate to contact us and we'll be glad to help!


Example Cellar Calculation

Cellar Size 10'W x 10'D x 10'H

1000 Cubic Ft

Insulation

R19

Cellar Interior Temperature

55°F

Peak Ambient Temperature

85°F

Single Pane Glass 10'W x 10'H

Single Pane 100 Square Ft

Heat Loss Table Result 37.80*100

3780 Additional BTUH

Standard Thermal Load Result

3508 BTUH

Final Thermal Load of Cellar

7288 BTUH