accurite is junk, or is it ranco that is junk?

[bbrewer07]

I had a cheap thermostat for my uth and the temps shifted from 85 til about 93. I have an accurite temp. I checked out what a good thermostat was on here and everyone highly recommended the ranco or johnson. I spent 80 bucks and got the pre-wired ranco. My thermostat probe and the accurite probe are both under half inch of substrate(cypress mulch) directly on the glass above the uth. Guess what, my temps still change just like the cheap thermostat, 84 to about 91. Which one is junk, the accurite or ranco?

[Kristy]

When you set your Ranco up and programmed it, what did you set your Differential Range to?

To add to that, it probably isn't the Ranco. I would check what you set it to first. Then go from there.

[Stewart_Reptiles]

Ranco is a non-proportional thermostat, that will cut on and off, so the temps will vary.

What did you set it on? And what is the differencial?

This is from Reptile Basics thermostat FAQ

They turn on 100% when the temperature falls a degree or two below the set point and they stay on until the temperature gets a degree or two above the set point. This means that if you set your thermostat at 80 degrees your actual temps can vary between as low as 76-78 degrees and as high as 82-84 degrees.

[bbrewer07]

I set my differential to 1-I hate to get a whole new accurite and set it all up, it seems like its right most of the time, my thermostat kicks on and off, just not quick enough(my outlet has red light on it so I know when it is on and off)It seems that when it kicks off the temp is 91 like it should be, but by the time it kicks back on it takes awhile for it to warm back up therefore letting my temps drop to far? I dunno

[JLC]

How long have you let it sit undisturbed? Sometimes it can take a while for things to settle down...especially if you keep opening the cage/tub or otherwise messing around with it.

Also...what kind of UTH are you using? It's possible that the problem isn't with your t-stat. A cheap UTH may not be heating reliably.

[Kristy]

I also forgot to mention I have had Acurites crack out on me too. When the battery runs low at all, the temps flucuate really bad.

If you have an older battery in there try replacing that too.

[bbrewer07]

They both are about 2 weeks old and sit all day undisturbed while I am at work. What is the point of setting the temperature differential to a 1 degree difference if it is going to let it fluxuate about 6 degrees?

[Kristy]

It shouldn't flucuate, at least mine doesn't. Maybe I am lucky with mine. The most it ever flucuates is a degree or two but thats it.

What are you using to hold the probe in place? I have learned the hard way to keep the probe on the outside of the tub/tank.

Houdini has moved his and the temps went haywire. If the probe is off the heating device at all it will flucuate quite a bit.

[Mindibun]

My temps will do that too but I've learned that its the accurite. Like someone said, if the battery is even the tiniest bit low, it takes horrible readings. Keep tons of extra batteries on hand.

I'm more likely to trust the $90 machine than the $12 *batteries required machine. Y'know?

[elevatethis]

1. Trust the ranco.

2. Secure the probe to the heat source on the outside of the tank somehow. With 2" of substrate, you may need to turn the Ranco's temperature setting a few degrees higher than what you want your hot spot inside the cage to be. Then, measure the hot spot inside the tank with the accurite and adjust the Ranco accordingly.

Hope that helps.