Wife has wanted a greenhouse for a while now. So I have bought her one of the 10*14 polycarbonate twinwall kits for Christmas. We live in southeast VA (zone 7b I think) I have a bunch of free supplies I plan on using as part of the heating/cooling system. Old bricks for the floor, a 300 gallon water tank I plan to bury under the floor, and a massive radiator as a heat exchanger (its from a big rig truck)….I will need to get a pump and a fan setup, but my question at the moment is, is there a such thing as too big of a heat exchanger (radiator)??
by TeslaFarm
2 Comments
The limiting factor is how much air you can move from the greenhouse through the heat exchanger.
The surface area and material of the heat exchanger is a factor that will determine the volume of air that can be heated. The flow rate of the coolant is also another major determining factor in how much heat can be transferred to the material of the heat exchanger and then into the surrounding air.
By regulating the flow of the coolant you can determine just how quickly chilled/heated coolant cycles through the radiator, which will control the rate of heat transfer.
You may also want to consider building a multi stage thermosiphon system that you can use to passively heat or cool the coolant in your reservoir.
https://www.google.com/search?q=thermosiphon
You could use a lowered solar thermal panel to passively heat the reservoir throughout the day during winter, and a raised radiator behind the greenhouse to cool the reservoir at night during the summer.