Heating tubs?

Trollbie · 05-20-12, 07:26 PM

At first I had a small ZooMed UTH under eat connected to a rheostat. Everything was great and stable for 4 days and then it got too hot for some reason even though I didn't change the settings on the rheostat. The other UTH that's connected to the same rheostat is fine.

I got a bigger UTH since that one was too small anyway, and glued bottlecaps on the bottom of the tub to increase the airflow underneath. Left the rheostat on low. Everything was fine for a night and then within a couple hours the next it got hot enough to melt the plastic a little. I was checking the temps with a temp gun every couple hours and it was stable. So I'm not sure what happened.

Then someone recommended a human heating pad. So I bought a new tub and a Sunbeam heating pad. Everything was perfect until I realized that it has a auto turn off after 2 hours and has to be manually turned back on.

I looked but they don't sell them without the auto shut off anymore. I could try opening it up and disabling the timer on the circuit, but I'd rather take an easier route if there is one because if I screw it up then I can't return it.

What could I do with the UTH to not attach it to the tub, but still have it heat the tub enough? I'd get a thermostat, but at this point I don't trust the UTH on the plastic anymore because the second time the heating pad wasn't even that hot. I could touch the tub and it was warm, not hot, and it still melted a little.

The tub I'm using is a Sterlite tub

youngster · 05-20-12, 07:37 PM

Rheostat= bad. That's your problem, get a real thermostat and this won't happen. And just stick with a ZooMed UTH/flexwatt.

As long as you have a thermostat you will be fine, plenty of people use UTHs on plastic, just don't set it above 90.

Trollbie · 05-20-12, 07:41 PM

Quote:

Originally Posted by youngster

Rheostat= bad. That's your problem, get a real thermostat and this won't happen. And just stick with a ZooMed UTH/flexwatt.

As long as you have a thermostat you will be fine, plenty of people use UTHs on plastic, just don't set it above 90.

But it only got hot enough in the middle of the pad. And even then it wasn't THAT hot... I'd rather not put the UTH directly on the tub anymore, but I don't really know if cardboard or foil or something in between the UTH and the tub would help.

hellosugaree · 05-21-12, 12:30 PM

Quote:

Originally Posted by youngster

Rheostat= bad. That's your problem, get a real thermostat and this won't happen. And just stick with a ZooMed UTH/flexwatt.

As long as you have a thermostat you will be fine, plenty of people use UTHs on plastic, just don't set it above 90.

Agreed. A rheostat doesn't account for a hot day where your ambient room is 10 degrees hotter than it was on the day you set it up... a thermostat does. A rheostat also doesn't account for the quality of your heating pad or whatever else that may not have consistent heat output, whereas a thermostat will. Get a decent thermostat and you should be fine.

Trollbie · 05-21-12, 12:32 PM

Quote:

Originally Posted by hellosugaree

Agreed. A rheostat doesn't account for a hot day where your ambient room is 10 degrees hotter than it was on the day you set it up... a thermostat does. A rheostat also doesn't account for the quality of your heating pad or whatever else that may not have consistent heat output, whereas a thermostat will. Get a decent thermostat and you should be fine.

My room heats up by maybe, MAYBE, 2 degrees during a sunny day -_-

It's always cold here. Which is good because I hate the heat, but also bad because it's harder to get the temps right for my snakes.

hellosugaree · 05-21-12, 12:48 PM

Quote:

Originally Posted by Trollbie

My room heats up by maybe, MAYBE, 2 degrees during a sunny day -_-

It's always cold here. Which is good because I hate the heat, but also bad because it's harder to get the temps right for my snakes.

You must have 10 foot thick insulation and a very fancy room thermostat with evenly spaced vents all over the room. Most house central heat/ac systems have at least a 2+ degree swing on the set point and that doesn't include the fact that the thermostat sensor is in one room and all rooms do not heat or cool evenly.

I must say I'm impressed with the fantastic climate control system in your house.

Trollbie · 05-21-12, 01:02 PM

Quote:

Originally Posted by hellosugaree

You must have 10 foot thick insulation and a very fancy room thermostat with evenly spaced vents all over the room. Most house central heat/ac systems have at least a 2+ degree swing on the set point and that doesn't include the fact that the thermostat sensor is in one room and all rooms do not heat or cool evenly.

I must say I'm impressed with the fantastic climate control system in your house.

Don't be. My room is shaded by trees so we get no sun. The way it's facing, it wouldn't get much sun anyway actually. The house heater could be running all day but make no difference in my room because the only vent is the bathroom (I'm in the master so my roomie and I get our own bathroom) and that vent doesnt work or I don't know what's up with it, but no heat comes through.

So while our other housemates are nice an cozy during the winter, my roomie and I sleep in sweatshirts and under at least 2 blankets. I would think we have hardly any insulation.

youngster · 05-20-12, 07:46 PM

Well get a thermostat and raise it on bottlecaps like you did. Problem solved.

If you place the probe properly I don't see how it could get hot enough to melt the plastic even a little.

Trollbie · 05-20-12, 07:53 PM

Quote:

Originally Posted by youngster

Well get a thermostat and raise it on bottlecaps like you did. Problem solved.

If you place the probe properly I don't see how it could get hot enough to melt the plastic even a little.

I still won't trust it. It was okay this time because I was home to keep checking on it, but that won't be the case during the week. I don't want to risk it.

youngster · 05-20-12, 08:44 PM

Hmm, I'm not sure what you're hoping to hear then.

Can you make a new enclosure?

Trollbie · 05-20-12, 09:17 PM

Quote:

Originally Posted by youngster

Hmm, I'm not sure what you're hoping to hear then.

Can you make a new enclosure?

Not till august

**millertime89** · 05-20-12, 10:49 PM

Already sent these pictures to Trollbie, but I'll post them here to show others my solution. I knew I wanted as little of a gap as possible, but I couldn't find something that I really liked that would work so I spent a half hour or so wandering around Home Depot and eventually came up with this.
Here you can see there's less than a half inch of space between the UTH/flexwatt, but still a gap so its not actually touching the plastic, just the wood.

Here's what I use as spacers, copper plated adjustable brackets, they were less than $.50 USD IIRC.

the extend too which is nice. I don't think I've seen any tubs much wider than 20 inches.

I do take a hammer and flatten the ends so they lay flat. But if you do have a tub that's wider than 20 inches, it splits apart and you can use it as two pieces with a gap in between.

Trollbie · 05-20-12, 10:54 PM

Thanks KyKy!!! That's exactly what I was looking for!

**millertime89** · 05-20-12, 11:15 PM

No problem ZuZu, I tried finding them on Home Depot's site but couldn't, might just have to go and wander the aisles. I do that looking for tools sometimes anyways.

Trollbie · 05-21-12, 11:08 AM

What temp do you have the t-stat set to?