The Forestry Forum

General Forestry => Drying and Processing => Topic started by: vfauto on December 10, 2017, 11:20:58 AM

Title: Automating a solar kiln??
Post by: vfauto on December 10, 2017, 11:20:58 AM
If I was to  automate the vents and fans in my solar kiln with a thermostat, humidistat, timer and linear actuators to open vents what would the parameters be? In other words when should fans come on and off and when should vents open and close? Please be specific. ???
Title: Re: Automating a solar kiln??
Post by: GeneWengert-WoodDoc on December 11, 2017, 01:22:01 AM
Fans would be most efficient if run when the humidity inside is under 90% RH for green wood and under 65% RH for partly dried.  This will be an hour or two after sunrise until an hour or two after sunset.  You can use a timer and be very close at low cost.  Set new times about once a month.

Vents open to exhaust moisture.  However, when open they also exhaust heat.  So, we want to keep the RH at a high level initially and gradually drop the humidity by more venting as the wood dries.  Near the end we close the vents almost completely to get maximum heating so we can get low final MCs. No need to automate...just adjust things every 5 days perhaps.