I think it’s time for your nap. You haven’t stopped to take a breath in any of these frozen pipe threads for like 48 hours because everyone but you is wrong.
ETA and worthless. I forgot, you called me worthless in the other thread. Good times.
Carry on.
Yeah, there is heat tape on the water line, extending a short way below ground. Ideally it should extend further down, but that would require digging up a part of the barn that is inaccessible without removing walls.
And the GFI outlet the tape is powered from has failed. Not realizing how often GFI outlets fail, when it happened I assumed it was the heat tape and replaced it (a PIA job due to access). After replacing it I realized the outlet was bad.
ETA: even if the heat tape were 100% effective, water in the hose freezes.
That’s why farm supply stores sell “milk house” heaters. Set on low, turn the 'stat near low and let it keep your enclosed area a toasty 50F with a 500-700W forced air heat. I’ve thawed frozen vehicles with those and a large enough tarp. Just make sure you aren’t shooting at a combustible and your GFI works.
The OP is talking about a sewer pipe. Light bulbs, heat tape isn’t the answer.
With a correct slope, the 4 inch drain pipe shouldn’t freeze.
Me thinks the installation was bad.
Perhaps, though this makes me wonder - how do the traps on tubs work? I’ve never had them exposed. Isn’t the pipe coming down from a shower or bathtub coming down into a u-bend that always has water in it?
And isn’t that u-bend just exposed right there on the bottom in a mobile home?
If that’s the case, the OP would just need a very small section of heat cable over the u-bend.