The Forestry Forum

General Forestry => Drying and Processing => Topic started by: oakiemac on November 14, 2017, 09:13:46 PM

Title: Small shop propane heater for kiln
Post by: oakiemac on November 14, 2017, 09:13:46 PM
Thinking of installing small propane heaters in my two kilns instead of the hot water heat that I now have. Reason is the wood boiler uses a vast amount of firewood and I have to feed it every 4 hours or so. Thinking it would be much easier to just have propane heat.
My concerns are the lack of outside air in the kilns, maybe the heater wouldn't work correctly. Anyone do this?
Title: Re: Small shop propane heater for kiln
Post by: GeneWengert-WoodDoc on November 14, 2017, 10:51:45 PM
Fire danger high due to wood dust.

You will have to have some oxygen for the burners which means the humidity will be very low, which means possibly drying too fast.  If you go into the kiln to check samples, you need to make sure there is enough oxygen for you.

The advantage of your hot water system is that the hot burner gasses do not go directly into the kiln.  The same is true with using propane to heat a house...the hot gasses do not go directly into the air in the house.
Title: Re: Small shop propane heater for kiln
Post by: Crusarius on November 15, 2017, 07:27:57 AM
Propane is very moist and creates quite a bit of moisture in the air when heating.

I do think that you will need an outside air source. I definitely agree with fire danger being a concern.
Title: Re: Small shop propane heater for kiln
Post by: gasman1075 on November 15, 2017, 07:50:29 AM
A small direct vent heater in the kiln would not add moisture but if its very dusty and the dust is flammable that could be an issue. L B White makes tent and construction heaters that add heated air only by way of a portable duct and can be operated on a remote thermostat. The combustion process and exhaust and LP tank stay outside.

https://www.lbwhite.com/products/Tent-Heaters/Premier-Portable-Heater/
Title: Re: Small shop propane heater for kiln
Post by: oakiemac on November 17, 2017, 07:46:30 PM
I don't think dust is an issue but lack of O2 and a burning flame directly in kiln is a huge concern. I've kind of rethought the idea. Will check out LB whites heaters. Thank you
Title: Re: Small shop propane heater for kiln
Post by: Blackhawk1 on December 06, 2017, 11:14:06 AM
I have thought about other heat sources before and fire in our industry is a scary issue. I have a  no smoking policy on my property. Another issue I worried about in the kiln is it is a confined space and could there be out gasing that could be explosive, we know dust is. I am in the process of working out a hot water heating system to help with heating my kiln.
Title: Re: Small shop propane heater for kiln
Post by: GeneWengert-WoodDoc on December 09, 2017, 10:12:35 AM
We can ignite wood dust in the low 200 degrees F level.

What happens is that a couple of duct particles start burning air maybe 220 F and the heat they generate causes other dust to,start burning so fast that it explodes.  In a fire, we are converting a solid into gas, so huge pressure results.  As soon as a wall fails, then there is plants of oxygen.
Title: Re: Small shop propane heater for kiln
Post by: Texas Ranger on December 09, 2017, 12:01:23 PM
Not know what heaters you are using, fire them with propane outside the kiln