Data is always comforting. I certainly appreciated having a hygrometer in my first kiln. (An Accurite that was functionally rated to ~150ºF) Despite never being over about 130ºF in the kiln, the hygrometer ceased to function after about 10 to 12 months of use. By that point, I realized that I didn't really need it. The upper humidity limit is the point at which you get too much condensation within the kiln. The lower humidity limit is crispy dry leaf. If it cycles between these two, the kilning process is working just fine.
If there is
significant condensation inside the kiln:
- the Crockpot is working overtime to maintain the heat
--->improve insulation of the box
- the Crockpot power setting is too high
-->switch setting from high to low
If the leaf does not come into case, while temp is good:
- there is not adequate water in the Crockpot
-->increase the quantity of water added to the Crockpot
-->increase the frequency of replenishing the water
- the box seal is inadequate
-->improve the seal of the box
- the insulation is inadequate AND the seal is insufficient (requires too many watts to maintain temp)
-->improve the insulation and the seal
If it looks like too little moisture and too much moisture may both be indications of poor seal and/or inadequate insulation, that turns out to be the case. A well insulated and well sealed kiln will require less heating to maintain the temp, and as a result, the Crockpot will end up evaporating less water. A fan also improves the stability of both temp and humidity, and reduces power consumption and cycling.
To start off, improve the seal and insulation so that an empty kiln can maintain a stable temp on "Low". Fill the Crockpot nearly full, then check it daily, to determine how many days it requires to run dry. Check for condensation inside and outside the kiln. Now add leaf, and repeat the daily inspection. After a couple of weeks, you will have an excellent schedule for kilning, so that you add water when the Crockpot has run dry, but the leaf is still in case.
OR, you can install a hygrometer, and end up doing the same things.
Bob