Heating 101 Failing

[Codfather]

Hi,

I am completely new to all of this but have been reading for weeks. We have been preparing the enclosure for over a month but still aren't ready to buy our Leo yet.

I have a thermostat and a heatwave heat mat. The heat mat is an overseas version so it doesn't have a sticky face to apply to the bottom of the tank. Instead there are 6 small pieces of sticky Velcro for the edges of the mat.

When I used the Velcro it won't get hot enough. The heat mat has a dimmer and I have tried to measure even at full power but it pretty much sits at 84.2 when on medium or above. Is it possible I have a defective mat? How can I check?

It is easy to see that there is space between the heat mat and the glass. The retailer suggests that I put something non-flammable under it to keep it flat against the bottom of the glass. Any opinions on this?


The bigger picture. I am going to put my thoughts out there in the hopes that someone with actual experience will weigh in and straighten me out.


The thermometer turns the heat mat on and off to maintain the desired temperature range. This means that when the temperature drops the thermostat turns the heat mat on and then the heat mat heats up until either it reaches the maximum allowed by the dimmer or it reaches the upper limit set in the thermostat.

If the combination of the room temperature and the dimmer are right then the the thermostat doesn't need to do anything and the UTH will efficiently heat the enclosure. So if you can keep the room temp the same all the time things can be great.

On the other hand if the room temp fluctuates then it gets a little tricky. If I follow the advice of the local Retailers of the thermostat/UTH then I would set the dimmer to medium set my desired temps and leave it alone.

My problem with this advice is that if the room temps drop too low then the UTH may not be able to reach the desired temperature.

If the dimmer is set too high then the thermostat will turn off the UTH at the upper limit, it will take some time to cool down and then the thermostat will turn it back on and the cycle continues. It is hardly seems an efficient way to setup your heating.

The answer of course is a proportional thermostat that will adjust power proportionally to the UTH to maintain the target temperature.

So what should I do look for a proportional thermostat? Try to find that sweet spot setting for the dimmer on the UTH? If so how does one do so?

Maybe send hte UTH back and use CHE?

Thanks for reading the long post!!!

 

[acpart]

Getting the heat mat to stick to the cage: I'm not sure what country you're in, but if you're in the US, look for something (at Home Depot in the plumbing or electrical section) called Nashua Tape. It's shaped like a roll of duct tape, except it's shiny like aluminum foil. It tears more easily than duct tape: it's basically aluminum foil with a sticky side (there's paper on the sticky side that you tear off). This is the only thing I've found that will hold the heat mat to the cage without sagging. Tape it around the borders of the heat mat. For additional heat projecting upwards, tape a piece of aluminum foil over the entire heat mat, so the mat is sandwiched between the aluminum foil and the bottom of the tank.

Making sure the mat is working: look on the packaging to see how many watts it's supposed to be putting out. Get a watt-meter and measure. If you're not close, the mat isn't working.

Thermostat: you're right that the on/off thermostat will do exactly what you say. I do use fairly inexpensive thermostats (Alife or ESU) and have no problem with that. If it bothers you, get a proportional thermostat.

Good luck. Be aware that it can take several days in my experience for the floor of the tank to reach its maximum temp measurement with the heat mat (last summer I did a major tank switcharound and found this to be consistently true).

Aliza

 

[Codfather]

Thank you for the reply. I am still monitoring the temps. I had the upper limit at 32c and the lower limit at 30c but most of the time when I checked, the temp was at 32c(89.6f) so I changed the upper to 31c and the lower to 29. Now it is sitting at 29c(84.2f). I am aiming for 31c(87.8f). The built in Dimmer is wide open but I starting to wonder if I should close it up. Anyway time will tell.

Here is a pic of the testing phase. The hides still have to be painted and carved a little but it is a work in progress.

Thanks again for the reply.

 

[Terrain_pull up]

I was just running my rack on a dimmer switch with heat tape for almost a year. My wife and I ended up being walking proportional thermostats. The temps would vary slightly depending on room temperature as you mentioned though. As long as you have a decent IR temp gun to monitor how things are going it works. I found most of those store bought heat mats max out in the low 90's even if you just plug it straight into the wall.

All that being said, I recently invested in a proportional thermostat a few months ago and now I wonder how I got by without it! The extra cost is for peace of mind.

 

[Codfather]

Thank you for the reply. The temp gun sounds both useful and fun.

I hope to finish the hides this weekend. I emailed the distributor about the heat mat and they told me to use thick board to push the heat mat up against the glass. They also said that I will need a second heat source for above. I am a bit worried about the summer when we start using A/C. The rest of the year it shouldn't be too bad. I will update when I make some progress.

 

[Pinned27]

The thermostat turning off and then back on is ok. as long it isnt a big fluctuation in temps, your fine. I have mine set to 96 and it drops to 93.9 so im good there.
And also make sure your UTH is the right size for your tank. Should cover about 1/3 of the bottom. If its not working, like stated above, use a piece of aluminum foil to put over the UTH so it send the heat upwards. And the dimmer isnt really needed unless your trying to keep the temp the same without your thermostat kicking in.
And if your temps still dont get where you want them 88-95 range, jump up to a bigger UTH or if your close to the temp range get a CHE and use a light dimmer with it. Its all about trial and error and correction. I feel you i went through the same thing with my tank before i got my leo.