How to “Burp” Your Greenhouses
“Burping” the greenhouse is a method for reducing humidity and condensation accumulation.
Ventilation and heating in combination are most effective for reducing humidity and condensation formation. Ventilation allows the humid air to be released and drier air from outside to be brought in. Heating reduces the difference in air temperature that makes condensation form.
So just how do you burp a greenhouse?
- If the greenhouse has fans, turn them on for a few minutes, then off, before turning the heat on.
- Then turn the heat on and crack vents about one inch.
- For automated control, a relay is needed to turn the heat off when fans are on.
- Repeat the cycle two to three times every hour after sundown and at sunrise.
The capacity of your fans will determine how much air can be exchanged in a given amount of time. Some fans may take only 2-3 minutes, or if there is only natural ventilation, it could take as much as 30 minutes. This cycle works well during rain too.
Alternatively, horizontal airflow fans can be utilized with small fans placed along the sides of the greenhouse blowing into the production space. The fans should operate continuously except when exhaust fans are being run. This combination of circulatory airflow and air being pushed inward from both sides helps to mix the air to maintain more stable temperatures.