Flexwatt tape temp variability

[PsychD_Student]

Hey guys!

I have a question. I just finished building my new rack after I sold the old one. I just got the heat tape wired yesterday and the new Herpstat 1 hooked up. However, I have a problem!

I know that flexwatt can vary between shelves. All heat tape strips are wired in parallel and soldered on directly to wires. My problem is that one shelf is highly variably compared to others. Its significantly lower than the rest, about 11 degrees on average. It doesnt even seem as if its working at 83 degrees where the rest are at 95-- where they should be. Its also in the middle of the rack, so I'm not sure whats up with that.

Can you guys help me troubleshoot? Maybe you've had similar circumstances in the past?

Thanks guys! All help is greatly appreciated!!

[The Serpent Merchant]

Sounds like you have a bad connection on that strip. I would check your joints

[steeler]

Sounds like that one has a bad connector. It's probably only getting heat from the tub below it.

I would resolder the connections on that one.

[AMBiEN22]

My rack i have now, the first one i have built, i have 4 shelves with four flex watt heat strips in parallel as well and i encountered the same problem. From now on i think i am going to just run one continuous strip and snake it through the rack. This way so i know all the heat tape is functioning and it should be all at the same temp.*

*Note: I would expect maybe some cold spots in the heat tape, but this argument really boils down to the quality of heat tape.

Just wanted to add my two cents, and what i have learned. But i would definitely agree with the other two have previously posted.

[PsychD_Student]

Yeah... I started thinking about the connection as well earlier today. At first, I figured that if the connection was bad, all further flexwatt on the parallel further from the power source wouldn't work. But I now know that may not be the case. Considering they're all run in parallell, all the wires may be well connected together, but if only one of the joints isn't soldered correctly, then that single strip wouldn't work well.

I just finished soldering an extra strip of heat tape I have, and I'll try to change out the strip tonight. I hate soldering while they're taped to the rack (worst thing ever btw), so I soldered one on my table. Hopefully after I switch it out with this new one, it should work fine.

I'll keep you guys posted!!!! Thanks for the advice!

[kitedemon]

I run individual strips of flexwatt on my rack all are individually plugs to a wired strip of receptacles. I can unplug one level if it becomes empty or for cleaning with out effecting the rest. Water (disinfectant and electricity together don't sound like a good idea to me.)

[Robyn@SYR]

I run individual strips of flexwatt on my rack all are individually plugs to a wired strip of receptacles. I can unplug one level if it becomes empty or for cleaning with out effecting the rest. Water (disinfectant and electricity together don't sound like a good idea to me.)

Me too. I am not a big fan of the parallel wiring setup.

Are all of the lengths the same?

[kitedemon]

Yes they are. It was easy in my case it is older flexwatt and there is cut lines.

[The Serpent Merchant]

Yeah... I started thinking about the connection as well earlier today. At first, I figured that if the connection was bad, all further flexwatt on the parallel further from the power source wouldn't work. But I now know that may not be the case. Considering they're all run in parallell, all the wires may be well connected together, but if only one of the joints isn't soldered correctly, then that single strip wouldn't work well.

I just finished soldering an extra strip of heat tape I have, and I'll try to change out the strip tonight. I hate soldering while they're taped to the rack (worst thing ever btw), so I soldered one on my table. Hopefully after I switch it out with this new one, it should work fine.

I'll keep you guys posted!!!! Thanks for the advice!

If wired in series then if you have a bad joint then everything below won't work, but in parallel the strips below will work in most cases.

[PsychD_Student]

So I actually had a bad connection. One of the wires somehow disconnected. I suppose it wasn't soldered as well as I thought. I fixed it and it worked out fine. They are all the same length, and now they're all working well at the same temp. It all worked out for the best! I still prefer running my tape in parallel vs one strip or series, even if the troubleshooting can be annoying.

My brother who helps me with alot of my DIY stuff is a physics phd student. He went on this long rant explaining how theoretically running them in series will produce a less even charge on the flexwatt than running them in parallell. However, he wasn't sure whether or not the degree to which the charges differ from the beginning to end of the series is negligible. Any input those of you who do it in series?