Answer: In many areas gas, either LP propane or butane or natural gas, is used to heat a greenhouse. Regardless of the fuel, it is important to observe recommended venting procedures as well as maintain adequate air circulation and keep the eqipment in good running order. The following two discussions may be helpful to you in determining a satisfactory set-up for your greenhouse:
(Heating and Ventilation Systems)
http://www.wvu.edu/~agexten/hortcult/greenhou/building.htm (Planning and Building a greenhouse, includes heating and ventilation)
You may also find it helpful to discuss your heating plans with both the heater and greenhouse manufacturers, people who have greenhouses in your area, and possibly your local county extension.
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