Kiln Temperature Help

[Davo]

Just posting here as an update:

i switched out slow cooker for a spare one (it turns out it was noticed to be missing from the kitchen pantry lol). The slow cooker in use is now 150w and running on high.

I saw a small bit of mould in one of the bags (top shelf of kiln so presumably highest temp). I’m not sure if this is growing or is from the first couple of days when I was struggling to get temps above 50c. I’ll keep watching this.

I saw temp had dropped to 48 when I checked this morning, and is at 51 now 6hours later. I have changed the temp controller to kick back in at 52.5 as opposed to 51 as it seems my slow cooker is taking a while to get back up to temp.

I have two small computer fans on their way so hope to have these installed in the next day or so.

 

[Davo]

I think the 150w slow cooker was faulty as it was taking around an to raise the temp by a degree or 2. I have plugged the 250w one back in on high and it is causing the temp to rise by a degree in around 5mins.

 

[ChinaVoodoo]

I’m not sure if this is growing or is from the first couple of days when I was struggling to get temps above 50c. I’ll keep watching this.

You should remove it.

 

[ChinaVoodoo]

You're wasting too much heat through the door. You need to insulate.

 

[Davo]

I have placed two computer fans in the kiln and in the meantime put a couple of wool blankets over the front door.

I’ve had to put both of the fans at the bottom due to wiring etc (just using what I had lying around). However next season I will set these in different spots.

where abouts in the kiln do you guys have your fans set up?

 

[Knucklehead]

I have placed two computer fans in the kiln and in the meantime put a couple of wool blankets over the front door.

I’ve had to put both of the fans at the bottom due to wiring etc (just using what I had lying around). However next season I will set these in different spots.

where abouts in the kiln do you guys have your fans set up?

I have a bathroom exhaust fan set against the side of the box blowing upwards so it circulates around the inside. It blows quite a bit of air but doesn’t blow the tobacco around, it just keeps the air moving and keeps the temps and humidity distributed. I put it where it would be out of the way in a corner.

Knuckleheads Wooden Box Kiln Build

... the miracle of siphoning work to automatically fill the crockpot. Then it will always be full, which I found to not be a good thing. Others have been satisfied with that approach. Bob

fairtradetobacco.com

 

[ChinaVoodoo]

I have placed two computer fans in the kiln and in the meantime put a couple of wool blankets over the front door.

I’ve had to put both of the fans at the bottom due to wiring etc (just using what I had lying around). However next season I will set these in different spots.

where abouts in the kiln do you guys have your fans set up?

I have my fan inside a 6"pipe and my heat source is two 60W lightbulbs which are also in the pipe. The pipe blows upwards.

 

[Davo]

Today I timed how long it took from hitting the set temp (55c) until the slow cooker came back on. It was around 5hours.

just curious to hear how long your kilns’ off cycles are.

 

[deluxestogie]

Standing, watching my kiln's temp probe display fall by one degree F is a tedious, boring process. Maybe 5 to 10 minutes per degree. I would guess (please don't make me sit and measure it) that a complete cycle (set on High) averages about 60 to 90 minutes. This depends, of course, on the ambient temp on my porch. On a warm, sunny day, the cycle might be more like 3 or 4 hours. When my back yard is a frozen wasteland, the ambient temp on my enclosed back porch is more challenging.

Bob

 

[Davo]

So I did a reading to see what the power consumption of the kiln is over 24hrs. It came out as 5kw.

is this similar to what your kilns are running at?

I figured out that a 6week cycle would costs about $80nzd (60us), which even if I only had 50g of leaf in there instead of the 5-10kg capacity, it would still be half the price of a pouch of tobacco at the shop

 

[ChinaVoodoo]

So I did a reading to see what the power consumption of the kiln is over 24hrs. It came out as 5kw.

is this similar to what your kilns are running at?

I figured out that a 6week cycle would costs about $80nzd (60us), which even if I only had 50g of leaf in there instead of the 5-10kg capacity, it would still be half the price of a pouch of tobacco at the shop

Mine is about 1 kWhr in the winter when the garage is close to freezing. It's only 80W of light bulb and 10W of fan. Even if it ran 24 hrs a day, it would be 2.16kWhr.

 

[ChinaVoodoo]

So I did a reading to see what the power consumption of the kiln is over 24hrs. It came out as 5kw.

is this similar to what your kilns are running at?

I figured out that a 6week cycle would costs about $80nzd (60us), which even if I only had 50g of leaf in there instead of the 5-10kg capacity, it would still be half the price of a pouch of tobacco at the shop

Did you remember to include delivery/transmission in your calculation?

 

[Davo]

Did you remember to include delivery/transmission in your calculation?

By this you mean line charges etc?

 

[ChinaVoodoo]

By this you mean line charges etc?

Yes. They double dip on the same energy use.

 

[Davo]

Yes. They double dip on the same energy use.

Yeah I included all the extra charges and tax on top of the kWh unit price (30c). Here we pay a fixed daily connection charge (30c), a market fee for each kWh used (.3c) and 15% Tax on total bill.

If I wanted to further reduce the running costs of my kiln, would better insulation be the next step?

 

[ChinaVoodoo]

Yeah I included all the extra charges and tax on top of the kWh unit price (30c). Here we pay a fixed daily connection charge (30c), a market fee for each kWh used (.3c) and 15% Tax on total bill.

If I wanted to further reduce the running costs of my kiln, would better insulation be the next step?

Yes. Absolutely.

 

[ChinaVoodoo]

People in warm places seem to take insulation for granted.

 

[ChinaVoodoo]

The only sources at inefficiency in your kiln are sound/vibration, and transduction of heat. The amount of energy lost through sound is probably hardly measurable.

 

[Davo]

The only sources at inefficiency in your kiln are sound/vibration, and transduction of heat. The amount of energy lost through sound is probably hardly measurable.

I dunno, we have 3 kids 5 and under and our neighbour’s have 2. Most energy is lost through sounds round here.

I have 2 spare bags of insulation, about 2.5rh. I wonder whether I should build an insulated cupboard for the kiln to sit snuggly inside - or even a “U” shaped thingy I could slide down the sides till it sits flush against door

 

[ChinaVoodoo]

The sides of the fridge are probably already insulated. If I didn't want to spend any money, I would go to the recycle center or out behind an appliance store and would acquire and duct tape the thickest piece of Styrofoam I could find directly onto the glass. I might even try a few layers of bubble wrap. For extra measure, because heat rises, I would simply stack that bale of fiberglass insulation you have on top of the fridge. I wouldn't worry about encasing the entire thing until I tried those things.