HELP! Iffy Thermocube?

lucky1 · Post by **lucky1** » Tue Nov 12, 2013 10:42 am

Trying to figure out why the thermocube protecting the less-insulated (for now) Brahea armata didn't turn lights on when outside temp dipped to 0C 32F.
The other thermocube protecting teepee Washies went on, and Washies have MORE insulation.

Noticed that the Brahea's extension cord has those tiny lights at each end to show it's got power.

<a href="http://www.flickr.com/photos/southslope/10823269743/" title="003 by edible_plum, on Flickr"><img src="http://farm4.staticflickr.com/3710/1082 ... 386b19.jpg" width="375" height="500" alt="003"></a>

other end: <a href="http://www.flickr.com/photos/southslope/10823252223/" title="002 by edible_plum, on Flickr"><img src="http://farm6.staticflickr.com/5510/1082 ... 593940.jpg" width="375" height="500" alt="002"></a>

Questions:
1. Could the tiny lights on extension cord actually warm up the thermocube enough to affect its operation?

2. Do thermocubes fail after a few years?
3. Remote thermometers...are they reliable for, say, 10 years or do they slowly fail?

Barb

seedscanada · Post by **seedscanada** » Tue Nov 12, 2013 11:39 am

Barb,
1. Yes It can make a difference, but mine is as yours is and works fine.
2. Yes I prefer to keep a spare.
3. Yes they can fail in the first year, especially in a moist freeze/thaw environment. My Brahea has a new remote wireless thermometer to reassure me. No worries, if you've kept it dry, 32'f on the Brahea is no problem, if for a night. I've replaced my remote thermometer three times in the past three years, due to failure,

I Have lost sleep over questioning thermocubes and light bulbs.
To reassure me I use the remote thermometer as stated.

Separately (for the other eight enclosures) I make sure a t-cube controlled light is visible, even if only a glow to the box or a corner with a little bit of light visible through at night.

On my tiny boxes, (volunteer double Butia seedlings, ad separately, triple Phoenix dactylifera 'Medjool' I have 3 bulbs at 7w apiece on at all times. They are 3 different colours to make a quick visual reference whether any have burnt out.

And lastly, the thermocube for my temporary greenhouse is working, but i wanna know just by glancing out the window. I plan to plug in one or two LED lights from a string of lights to the thermocube as well.

When sitting at our dining room table last winter, I felt assured by the intermittent glow of my Brahea box and the +positive celcius readings on the remote thermometers.

Good luck. Oh and ordering a spare t-cube couldn't hurt for piece of mind.

Cheers!

lucky1 · Post by **lucky1** » Tue Nov 12, 2013 12:42 pm

I make sure a t-cube controlled light is visible, even if only a glow to the box or a corner with a little bit of light visible through at night.

Yeah, I like that idea too...the little light on the cord WAS on, doesn't mean the Tcube was working.

I'm with you on that...the reassurance of the glow, but with 3 protections this winter, I've used up my spare Tcube.

I even tested them all by putting them in the freezer with a string of lights.
They all worked but (of course

) I forgot to put a temp sensor on them to see WHEN they went on.

Found another string of lights...may add that

BTW, Home Depot says they won't stock Tcubes.
I told them "bet you stock them for folks in Florida, as though they need a Tcube"

So it's back to ordering from aartech @ $25.99 each PLUS $15 shipping.
And they're only $12.99 in the USA box stores.

Oh, and HD was out of remote thermometers too.

Thanks Adam!
Barb

TerdalFarm · Post by **TerdalFarm** » Tue Nov 12, 2013 1:12 pm

sorry about H-D. Yes, they are cheap down here, so I'd keep extras on hand. Maybe I should mail you a box of 20 and you can set up an eBay store up there?

As for testing them, what I use to do was put them in the freezer for a bit to et them cold, then test them. Can you do that?

What I am hoping is that your Brahea box simply didn't get cold enough.

lucky1 · Post by **lucky1** » Tue Nov 12, 2013 2:03 pm

put them in the freezer for a bit

Did that, but didn't include a thermometer to see at what temp it activated the lights.

Or is it a case of: they work, or don't work at all.
I'm worried the temperature at which a T-cube activates might fluctuate as T-cube ages.
Is that likely?

I have ZERO electrical knowledge (like you didn't guess that already

)

Barb

TerdalFarm · Post by **TerdalFarm** » Tue Nov 12, 2013 5:59 pm

Hmmm...I guess I know as little.

My assumption is that they work or do not. So, they worked after the freezer test?

lucky1 · Post by **lucky1** » Tue Nov 12, 2013 7:07 pm

The T3 thermocube and string of lights were placed IN the freezer.
Yes it turned lights on, so it works.
But at what temp ???

But hasn't worked once I returned thermocube to the Brahea armata teepee.
The remote was reading 0C 32F.
A T3 is supposed to activate at 1.6C 35F.

Something's wonky...remote thermometer? T3? extension cord?

The only good thing is that this is happening now instead of January when the Brahea would be a corpse.

Barb

seedscanada · Post by **seedscanada** » Wed Nov 13, 2013 7:28 am

Barb, 25 plus 15 bucks? Nononono. eBay:
http://www.ebay.ca/itm/ThermoCube-Therm ... 1#shpCntId

That's 17 and ten. They offer combined shipping. You would have paid 40 for one. here you can get one for 27 or two for ($44?)

I always look at ebay, even more options at ebay.COM

lucky1 · Post by **lucky1** » Wed Nov 13, 2013 8:18 am

Thanks Adam, appreciate the tip of where to buy.

Yeah, I even emailed aartech and asked why $15 bucks to ship an 8-ounce item.
Got some ridiculous answer about shipping contract.
Ergo "kickback",

Barb

TerdalFarm · Post by **TerdalFarm** » Wed Nov 13, 2013 10:06 am

Hmmm...maybe try again. Personally, I wouldn't worry for Brahea if the thermocube is a few degrees off, as long as it kicks in. Nice thing about Brahea, vs (e.g.) Bismarckia is the safety zone (8 vs 9). But: I lost Brahea in a heated greenhouse in 2011 so know they are zone 8 and not zone 7. Make sure those thermocubes work, please.

lucky1 · Post by **lucky1** » Wed Nov 13, 2013 10:21 am

I lost Brahea in a heated greenhouse in 2011

Yup, they're worth the effort.
At least so far

And so far, our projected cold hasn't arrived.
But it will in 3 days...aaaargh!

Thanks Erik.
Barb

JackLord · Post by **JackLord** » Wed Nov 13, 2013 10:32 am

What a coincidance. I suspect my Thermocube is wonky as well.

I was waiting to see it if would activate last night at 35 F. It was 11:30 pm and still 36 F outside. I could not stay up any longer. It was on this morning but then stopped while it was still 32 F. Then it went back on.

Perhaps time to procure a new one.

lucky1 · Post by **lucky1** » Wed Nov 13, 2013 10:37 am

Yeah, it shouldn't go off until 45F.
Or maybe sunlight was warming the protection for a while?

JackLord · Post by **JackLord** » Wed Nov 13, 2013 12:50 pm

lucky1 wrote:Yeah, it shouldn't go off until 45F.
Or maybe sunlight was warming the protection for a while?

I thought that might be the case. It was 39 F in the greenhouse. The cube is in an outlet on the front porch which may get warmer quicker than everything else.

Still, it went off and then on again and that never happened when I used it last. Admittedly that was at least three years ago, I think.

lucky1 · Post by **lucky1** » Wed Nov 13, 2013 3:20 pm

You haven't used it for 3 years?

cube is in an outlet on the front porch which may get warmer quicker than everything else

The T cube should be where the temp protection is needed.
i.e. at the palm, connected to the string of lights.

Or maybe I misunderstood what you posted.

Barb

TerdalFarm · Post by **TerdalFarm** » Wed Nov 13, 2013 5:11 pm

I put the part of the cube where the temperature sensor is located close to sensitive plant tissue (i.e., the spear base) but far enough from heat sources (i.e., light bulbs) that is does not turn off as soon as the light bulbs heat up.

JackLord · Post by **JackLord** » Thu Nov 14, 2013 9:44 am

lucky1 wrote:You haven't used it for 3 years?

cube is in an outlet on the front porch which may get warmer quicker than everything else
The T cube should be where the temp protection is needed.
i.e. at the palm, connected to the string of lights.

Or maybe I misunderstood what you posted.

Barb

I am not using it to protect a palm. I procured a 6 x 6 portable greenhouse to overwinter the Citrus and other Tropicals. The basement in the winter is too dry.

I am using a protable oil heater to heat the greenhouse. So if I put the Thermocube at the source, it will never shut off as it will be inside the already-warmed greenhouse.

The outlet is the same one I used when I was protecting a Butia inside another smaller greenhouse.

So it goes Outlet>Thermocube>Exstension Cord>Heater

lucky1 · Post by **lucky1** » Thu Nov 14, 2013 11:55 am

it will never shut off as it will be inside the already-warmed greenhouse

Understand now, thanks.

hardyjim · Post by **hardyjim** » Thu Nov 14, 2013 12:10 pm

Barb

I know you did not have a sensor in there but even if you did
there can be a few degrees difference in accuracy of the thermocube
and the sensor which makes the actual spread in temps a little tricky
to pin down-my Washy would go on somewhere between 31-34F.

Bottom line is -if it is working and is off a few degrees it won't matter
as your plant will not-ever- freeze even if the Therm comes on at 32F

lucky1 · Post by **lucky1** » Thu Nov 14, 2013 3:10 pm

Good point Jim....a few degrees variation.

But I did have a sensor in there, that's what alerted me to thinking the lights should've come on by now...
The Brahea armata will be tougher to keep happy than the Washies.

I'll just move the thermocube to a colder spot in the protection, away from the house.

Cold arrives here this weekend.
And midwest/east folks will be wearing shorts again.

Thanks.
Barb

teebee · Post by **teebee** » Thu Nov 14, 2013 4:11 pm

lucky1 wrote:And midwest/east folks will be wearing shorts again.

Looks like shorts an umbrella's

It will give me one last chance to tarp up lawn furniture and tape up the palm boxes and give everything a last once over...