Problem with Thermostat and Flexwatt

[Jay_Bunny]

We set up the thermostat on the new rack on Sunday. We didn't have thermometers in the tub but we thought we'd give the thermostat a chance to heat up. We put a thermometer on the cool side, the hot side and added a hygrometer to the top tub last night. At first, both thermometers were saying it was below 80 on each side of the tub. We checked the probe to the thermostat and found it wasn't positioned quite right. We re-taped it to the flexwatt and have been monitoring the temps since about noon. The temp on the hot side, with the thermostat set to 92, is 81.4. The ambient room temperature is about 79. Any idea why this won't heat up?

[JoshJP7]

What kind of thermostat do you have? Are you using a tub or glass?

[xdeus]

The thermostat probe is taped directly to the flexwatt, correct? In that case the thermostat reading will always be higher than in the tub because of such things like the insulating properties of the tub and any air gap between the tub and the flexwatt.

Adjust the thermostat settings up so that you get the desired temps in the tub.

[Jay_Bunny]

We are using tubs, a 32qt rack. There is no substrate in the tub at the moment. The thermostat is a Helix DBS1000 Proportional. So basically we have to set the temp higher than what the temps should be on the hot side?

[xdeus]

We are using tubs, a 32qt rack. There is no substrate in the tub at the moment. The thermostat is a Helix DBS1000 Proportional. So basically we have to set the temp higher than what the temps should be on the hot side?

Yep, although you should only have to bump the the thermostat temps by a couple of degrees. I just looked over your ambient and hot side temps, and it seems a little off. How and where are you measuring the warm side temps? They should be measured in the hide and in a part of the tub that is over the flexwatt.

[Blue Apple Herps]

Are you sure your flexwatt is actually heating up? Does the Helix give a read out of the amount of power being delivered? I had this happen on one piece of flexwatt; my Herpstat kept saying 100% output, but it was only getting to ~80; which was the ambient temp anyways. Turns out I had a poor connection. I re-soldered it and it worked, and is working, perfectly at its correct temp.

[ivylea77]

I ususally have to set my t-stat around 8-9 degrees higher than the temp I want when I use 11" flex. My herpstat is set to 104* and my Helix is set now at 106* With those settings I get the 92-94* I want. In my other rack using 3" I set my herpstat at 96* to get the 92-94* in my hot spot. My ambients are around 78-80.



Hope this helps. I also tape my probe directly to the flexwatt with lots and lots of duct tape covering the probe.

[Jay_Bunny]

We set the thermostat to 104 and we are waiting to see how the temps do at that setting. When we left the room it was at 90.

[dalvers63]

For our rack, I cut off a piece from an extra tub I have and put the probe on that before attaching it to the flexwatt. I then set the Helix at 96 and get 92-94 on the hot side of the tubs.

I got this idea from one of the rack plans I've come across and found it a great way to get correct temps without turning the thermostat all the way up.

[kavmon]

imo, i wouldn't want to set the stat much higher than 94-95 to get a hot spot arouns 90-94 in the tub.


make sure the stat probe is taped directly to the flexwatt in the rack.

usually the accurite probes can/will be a couple degrees off, not a big deal since it basically just gives you a ballpark on the temps.

i would trust the helix stat more than the accurite.


vaughn