Drolet EE1200 Little Sawman Instruction & Operation Manual page 20

3- Wind can also be a third cause of negative pressure. When your house is located
near a structure which height is superior to your roof's, wind currents can create an
interference with your chimney, leading to negative pressure problems.
Drawings #1 to #5 starting on page 18 will help you understand the explanations
provided in this section.
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