>>1) will the warm flexwatt cause any release of chemicals or odors since it will be sandwiched between latex paint and linoleum?
Latex paint No once cured, Linoleum only if rated for use above radiant floor heat.
>>2) Where should I put the thermostat probe in the cage?
On the hot end ina position to monitor basking temps.
>>layed on top of the linoleum at the bottom inside the hide?
If that is the intended basking spot.
>>outisde the hide box on the flexwatt side?
Basking spot?
>>outside the hide on the non-flexwatt side?
Only if the flexwatt is intended to heat the ambient temp of the cage and you have another source of basking heat.
Ideally the thermostat probe can be placed anywhere. However the displayed temp may not be the temp of the basking spot. Example, in my T10 the heat rope is beneath the plastic floor the probe as well. If you look at my thermostat the temps are between 95° and 105° but the inside area of the cage is about 92° directly on the basking area. If I were to set the thermostat at the actual temps the cage would be to cold. The other end is in my DIY 41 qt rack the probe was half way up the back of the enclosed rack about 2" above the floor in the middle tub slot. Because the rack was enclosed the thermostat actually was reading 90° as a high and I was achieving basking temps between 92° and 95°, so placement and your interpretation can be different. Always use a temp gun to validate temps.
>>3) Does this all sound like a safe plan for my ball pythons? I would really really appreciate your advice and help.
As long as teh animal can't sit directly on the flex-watt you should be safe, however most users recommend against using heat tape within the enclosure. As it can overheat and can get hot spots particularly when sandwiched between material with no air space.
You best bet would be to cut out the floor where the tap is to be placed, then lay your linoleum, or a thin sheet of plastic and attach the tape to the underside. Then using some reflectix insulate the bottom of the heat tape. This would be the safest choice. You can also stick your probe in their as well but remember your temp will need to be adjusted.
Good Luck
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Jeremy Payne
JB Reptile
1.0 Snow "Kahl"
0.2 Triple Het Moonglow "Kahl"
0.1 Orange Tail Hypo Het Leopard
0.1 Double Het "Sharp" Snow
1.0 Ghost
0.1 DH Ghost
1.1 "Kahl" Albino
1.0.2 Hypomelenistic
1.3 Pastel Hypo
0.1 Anerthrystic
0.0.2 Normal
1.1 Morelia Clastolepis