this post was submitted on 27 May 2026
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hmmm
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This makes total sense but how does this not go boom? No oxygen in the gas line?
Exactly that.
So you're saying you should poke a hole in the line?
That would just make a jet fire. Which may eventually result in the catastrophic failure of the pipe but if you really want to see a house jump cut a slot. Much more area for gases to mix. It's only 1psi probably so a hole may not be enough.
Autoignition temperature of natural gas is above 500c. Need a spark, or enough heat, there could even be a leak and this not be enough heat to ignite.
I’m pretty sure if it’s red hot it’s close to if not over 500°C but I guess it depends on the metal.
At least according to this Wikipedia article. https://en.wikipedia.org/wiki/Red_heat
My understanding is that it doesn't really depend on the metal much. It's just the blackbody radiation associated with that temperature. So basically anything glowing red from heat is probably over 500°C.
"As the object increases in temperature to about 500 °C (773 K; 932 °F), the emission spectrum gets stronger and extends into the human visual range, and the object appears dull red."
https://en.wikipedia.org/wiki/Black-body_radiation
The intensity does depend on the emissivity of the material, and emissivity is a bit counterintuitive:
https://www.engineeringtoolbox.com/emissivity-coefficients-d_447.html
But less than you’d think, given the extreme coefficient, as human perception of brightness is nonlinear. An object twice as bright as another looks pretty similar to the eye.
Thanks for the correction. I'm absolutely not gonna pretend I fully understand this, but isn't it still the case that anything glowing red from heat pretty much has to be over 500°C? I.e. https://en.wikipedia.org/wiki/Draper_point ?
Oh yeah, for sure. That pipe is hot.
Thanks!
So when you say "Autoignition", then ignition of what? For natural gas to "ignite", as in burn or in other words oxidize, there need to be an oxidizer present.
Autoignition here is referring to the temperature at which it will ignite immediately upon mixing with oxygen. Below that temperature, they can mix and not burn (like what happens with a gas leak).
Until the gas leaks from the weakened line and finds the oxygen in the room.
That was my thought as well.
So electrician/plumber/HVAC/gas co/exorcist? What are we looking at here?
Electrician, then gas tech? Otherwise exorcist?
That flex tube probably needs to be replaced. I'm not trusting my life to that thing anymore. I might even want them to check the rest of the gas plumbing to be sure.
Ok, if the tube is still glowing after it's been removed, that's when I'm calling the exorcist.
Someone bonded ground to the gas pipe not the water pipe.
So s8nce you seem to know what you are talking about how can this be fixed? A good ground rod by the gas meter?
Code requires bonding for all Corrugated Stainless Steel Tubing installations, but these "appliance connectors" get an exception for some reason.
Stupid question probably:
Couldn't I use it as default neutral and heat the water with it?
Edit: Obviously not the gas pipe itself, but I'm not really familiar with gas boilers, do didn't think of that
But can't I use a normal/real neutral to heat the water?
This is very obviously bullshit, what I'm thinking, but if the stuff in the house still works, while heating up this tube that much, I'm wondering, if that energy can't be used somehow
You're thinking of an electric water heater. That's literally an electric water heater. Safer and more efficient than simply electrifying the gas line to your water heater...
Yeah, shouldn't have posted
Was a drunk and tired half thought, where I even knew during posting, that it's stupid
Obviously fixing it and putting the energy where needed is more effective
Just thought, that this seems to be a major loss of energy and how to not lose it.
Fixing it is obviously the way to go ;-)
No, you're right though, electric water heaters are far more efficient. Especially if you have solar.
Turning electricity into heat is pretty much 100% efficient, but all the other conversions have outrageous conversion losses. Regardless, using solar is still the best option overall.
However, fossil fuels are still widely used, and that’s where the losses play a significant role. In that context, using gas to heat water is the simplest and most efficient setup. Converting the combustion products into electricity just introduces additional losses, further decreasing the overall efficiency.
Burning fossil fuels to boil water to create steam to spin turbines to generate electricity to transmit to the residential grid to power your electric kettle to boil water.
Or residential solar cells capturing sunlight to convert to electricity to power your electric kettle?
~(And don't forget that the fossil fuels were originally sunlight that was captured by plants that died and became fossil fuels that were extracted to be burned...)~
Thanks for being kind, my logic was still bullshit ;-)
I was somehow wondering, if we lose that energy there anyway, without appliances failing, we could use that as heat source - which isn't too bad of an idea, but just fixing it and using an electric heater would be the actual solution.
I'm still fighting with a fever and headaches since my last business trip and I'm just not that bright at the moment.
And heavy painkillers lowers my inhibitions to just vomit out my thoughts without further reflection ;-)
Electric water heater + water-based heat distribution & radiators
Voila
What I was thinking, was using an AC in my office and using the waste heat to heat up the water in my boiler
The HVAC technician I talked about that laughed at me and said, that's science fiction
But I don't really get why.
Wouldn't that be just a heat pump from the perspective of the boiler and an AC for my office?
Edit: to clarify, I'm aware, that I can't heat up the water to the level I want with that, but I could pre-heat it, so I don't need so much power to heat it the rest of the way
Edit 2: and I guess, there is my answer
My boiler usually doesn't get that low on heat, that this would really make an impact, as it usually hotter than the waste heat
Still, I think, there should be a way to gather the waste heat somehow
You'd need a custom rig to do that, the exact hardware probably doesn't exist. Maybe someone has instructions for a similar DIY project out there.
I'm not gonna dissuade you from tinkering because maybe you'll invent something cool. There might be a better way to reuse the heat from a freezer or a fridge or an A/C, even if it's not to boil your water heater.
Maybe it could keep your plants warm in the winter, or heat your toilet seat, or your aquarium, reptile habitat, or hamster tank. Maybe it could warm up some blankets, our some pouches of sand or pebbles that you can put under your blankets. Maybe warm an incubator or a humidor or a dehydrator. The world is your oyster.
Yeah I guess. But it's not free energy it's just extra load on the circuit.
That is the gas line.
Yeah, figured that too late
Pre-heating the gas should make it more efficient. I know you meant to do this with water, but this would recover some of the energy this way too. It's just incredibly dangerous.