I am going to install a heating cable in our incoming fresh water supply at the vacation home.
The water pipe runs above ground (insulated) about 4m under the house and then about 30m buried down to a "well" where the drop-off point is. In the well, it is frost-free so no worries there.
It's really the first 4 meters above ground that is the problem area and where it usually freezes. We currently have an external heating cable but it doesn't work well.
Now, as I said, I'm thinking of installing a heating cable inside the pipe instead. I'm considering buying a 25m heating cable and ensuring that it's safe and secure almost all the way to the well. I don't want to buy 30m because I'm unsure about the exact length of the water pipe, and it would be problematic if it's too long, right?
I heard from a plumber that modern heating cables are self-regulating along the entire length of the cable. Meaning, they only heat where it's needed. Is that true?
I've been reading product sheets all morning on different models and I can't find any information that suggests that.
For example, when I read about Frostvakt 10, it says that it's self-regulating but they still recommend having a thermostat. They also mention that you always get an increased water temperature when it's connected.
I can't reconcile that with it being self-regulating. If it were, it should turn off, not consume power, and not raise my water temperature if there's no need for it to be active.
If they are not self-regulating along the entire length of the cable, maybe I should just install a shorter cable where it's really needed to simply save some power. I will also install a thermostat, reusing the one I have for the external cable.
I would gratefully accept information about this from someone with experience.
There will be a follow-up thread regarding thermostat control later. Right now, I primarily want help choosing a cable and understanding how they work.
