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L200M question regarding the auto override temp switch

Started by jimbarry, November 23, 2022, 02:20:42 PM

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jimbarry

Loaded two cord today.



 

It will take two days running electric to get the heat up to about 120ºF where it will remain somewhat stable. I was thinking about supplementing the heating with propane to bring up the core temp of the firewood quicker.

If I use the propane and the air being blown around gets over the compressor's temperature safety limit, let's say 160º or so, will anything happen to the compressor? The switch that shuts off the compressor when it gets too hot, does that only function if the compressor is on? 





K-Guy

It's a pressure switch, so the compressor has to be running.
Nyle Service Dept.
A common mistake people make when trying to design something completely foolproof is to underestimate the ingenuity of complete fools.
- D. Adams

jimbarry


doc henderson

direct fire propane heat will add some water/humidity to the kiln, but overall should lower RH.  at the end of the heat cycle, consider opening up to vent humidity if the water content is more than the DH can pump out.
Timber king 2000, 277c track loader, PJ 32 foot gooseneck, 1976 F700 state dump truck, JD 850 tractor.  2007 Chevy 3500HD dually, home built log splitter 18 horse 28 gpm with 5 inch cylinder and 32 inch split range with conveyor powered by a 12 volt tarp motor

jimbarry

Doc, its been my experience that all we have to do is load and let it go until the avg MC is 20%. One thing I did learn is that once the thermal mass of the kiln's contents is up near 120ºF (generally 1-2 days of heating), I can shut off the heater and just let the heat generated by the fans and compressor itself get the temp around 115-120ºF. Which is plenty enough to keep the drain line dripping steadily. This time of year its taking 4-5 days to bring a load down to 20%. The cost incurred on each cycle is reasonable. I only wish now that we can do it quicker to keep up with demand. We now thinking about a 6-8 cord unit either propane fired of wood fired.

doc henderson

I think the key is a flue for gas fired heaters if you want dry air.  The net gain is prob worth it.  I was just throwing ut that a propane heater that vents to the space is also adding some water to the kiln.  the net EMC may be lower than without heat.  the DH will have some extra work.  Ideally the burned gas is exhausted to the atmosphere.
Timber king 2000, 277c track loader, PJ 32 foot gooseneck, 1976 F700 state dump truck, JD 850 tractor.  2007 Chevy 3500HD dually, home built log splitter 18 horse 28 gpm with 5 inch cylinder and 32 inch split range with conveyor powered by a 12 volt tarp motor

doc henderson

I have thought of using an old gas furnace or a wood fired forced air furnace.  could you preheat the wood in a separate insulated building then move to the DH kiln?  The unknown for me is the cost vs production.  efficiency.
Timber king 2000, 277c track loader, PJ 32 foot gooseneck, 1976 F700 state dump truck, JD 850 tractor.  2007 Chevy 3500HD dually, home built log splitter 18 horse 28 gpm with 5 inch cylinder and 32 inch split range with conveyor powered by a 12 volt tarp motor

Don P


jimbarry

Quote from: doc henderson on November 24, 2022, 07:39:30 AM
I have thought of using an old gas furnace or a wood fired forced air furnace.  could you preheat the wood in a separate insulated building then move to the DH kiln?  The unknown for me is the cost vs production.  efficiency.
A cost it would be. We don't have another insulated bldg.  Wood fired forced air seems to be the method. Less cost, more work.  The universe it seems always finds a way to balance the scales.

K-Guy

Jom
Be aware most heating appliances in North America have thermal overload that will cut the out at 104 F.
Nyle Service Dept.
A common mistake people make when trying to design something completely foolproof is to underestimate the ingenuity of complete fools.
- D. Adams

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