"It is a universal law - have no illusion - that every creature alive is attached to nothing so much as its own self-interest" - Epictetus
The above photo is where I spent a good chunk of my Saturday off. What you are looking at is the burner assembly for a natural gas hot water heater. I was trying to determine what was wrong before removing it from inside the water heater, and I also wanted a "Before" image. Below is what the assembly looks like when it's being posed for the photo.
First off, I'm not a water heater repair guy. However the mother-in-law called mid-afternoon Saturday to inform me that she had no hot water. I was pretty sure that no repairman was likely to show up during what remained of Saturday, and nobody would show up Sunday either. If they did, it would be a very expensive call-out. Even though I've never been inside a water heater before, I decided to attempt a repair. I headed over to see if I could fix it.
The pilot light was out. When I tried to light it, it would burn, but it would not stay lit when I released the start button and rotated the main burner knob. The instructions said to call a qualified service technician if that happened. All I had was me.
The large main burner gas pipe wasn't the problem, so I dismissed that. There are three smaller tubes that operate the pilot gas, which *was* the problem. One tube supplies gas for the pilot flame, and another is a spark ignitor. Both of those worked, because I was able to get the pilot flame to light.
The third tube is a thermocouple finger that sits at the center of the flame. The thermocouple is a safety device to stop natural gas from continuing to flow into your hot water heater and house in the event that the pilot light goes out. The thermocouple provides a 30-35 millivolt source of power to hold open the pilot gas valve, and once it gets hot in the flame, this will allow the
pilot gas to remain lit after you release the button. Very important!
As I said, I'm not a water heater repair guy, but the process of elimination led me to believe that the thermocouple had gone bad. Another possibility was that the pilot gas valve had gone bad, but this seemed less likely.
Below, the gas pilot and main burner control assembly. The top black button/knob is the pilot gas, the green button is the ignitor, and the large black knob is the main burner thermostat control.
The nearby Ace Hardware store had none (of course they didn't!!!!), so I had to drive about 20 miles round-trip to the Home Depot for a replacement thermocouple, below. Highly enlarged - the tubing is only a couple of millimeters in diameter.
I removed the old thermocouple and installed the new one, being very careful not to kink the copper tubing. Then I re-installed the burner assembly. Fingers crossed, I got the pilot light to burn, and lucky for me, this time it stayed lit when I rotated the pilot knob to the "ON" position.
So why did the thermocouple fail? I'm that guessing corrosive stuff in the gas burned a hole in the end of it.
The enlarged image (below) is a bit blurry, but if you look at the thermocouple finger, you can see white deposits on it. These deposits are from chemicals that are intentionally added to the natural gas.
Natural gas is primarily (about 95%) methane - CH4 - with minor fractions of nitrogen, carbon dioxide, ethane, propane, butane, pentane, heptane, hexane, and sulfur (in the form of hydrogen sulfide gas).
The natural gas transporter, who owns the long-distance pipeline, purchases natural gas from many different "producers". The producers are a variety of different companies that own natural gas wells. It is the producers' job to ensure that the gas they sell to the transporter is "pipeline quality". "Pipeline quality" natural gas has strict limits on how much of each fraction is allowed to be in the gas.
There are *very* low limits on sulfur, because that's what causes acid rain - and sulfur (hydrogen sulfide) also corrodes the pipeline. The preferred method for removing sulfur is to inject a scavenging chemical at the wellhead or gathering point for several wells. The producer is responsible for this, and the transporter always has the option to reject "non-pipeline quality" gas that contains too much sulfur.
As I mentioned in a previous post, natural gas prices have plummeted, due partly due to the shale oil and coal-bed fracking boom. They have also plummeted more recently due to the global economy going into a depression. Nat gas hit an all-time low of $1.65 per decatherm in April 2020, and has recovered only to about $2.65 today.
Natural gas producers are in a bad state economically: They borrowed tons of money to drill wells during the fracking boom. However, the current market price for natural gas doesn't support their loan expenses. As a result, these companies have switched from burning through borrowed money to drill and frack wells, to cost-cutting mode. The loans for drilling new wells dried up when the profits did. Drilling rigs are sitting idle, and these companies are laying off maintenance and operations staff.
But here's where it affects the rest of us: They've cut corners on the hydrogen sulfide scavenging chemical. When times were good, they used a better chemical to remove hydrogen sulfide. Now they seem to be using a less-expensive chemical that leaves a residue in the gas.
This new chemical seems to be causing a lot of problems, particularly where there is a reduction in gas pressure - like the regulator and meter outside your home, or at pressure reducing stations owned by the transport company. And it might be a little bit corrosive when it burns - I don't know. It definitely has left some deposits. Those deposits shouldn't be there, and can't be good for the pilot light assembly.
Anyway...
After I finished that long-winded project, I plowed the church parking lot. It hadn't been done since our last snowfall. Although the snow had mostly melted off, there were patches in the shade where snow and ice was still frozen to the asphalt. Due to my erratic work schedule, I'm the backup plow guy at church. However I didn't want anyone falling and getting hurt. I drove the 20 minutes to church and took care of it. Everything is a 20 minute trip: Grandma's house, work, town, church.
It was a busy day for a day off, and none of it was stuff that I needed or wanted to do. Maybe it's a karma thing.
Solstice.
Today is the winter solstice in the northern hemisphere. Most people think of it as the shortest day of the year, but it's not always. Sometimes the shortest day is the day before or after. The winter solstice is the moment when the north pole of earth points the furthest from the sun. After that brief moment of time, the pole starts coming back around.
Today on the northern hemisphere winter solstice, the relationship of the earth and sun look like the picture below:
Image By Rhcastilhos - Own work, Public Domain, https://commons.wikimedia.org/w/index.php?curid=1577426
Note above where the center ray from the sun lands. At the winter solstice, the sun will be directly overhead at the line where the Tropic of Capricorn is drawn around the globe. At the summer solstice, the sun will be directly overhead where the Tropic of Cancer is drawn around the globe. And of course, above and below each arctic circle, you get periods of continuous light and dark during certain times of the year.
The image below shows the lines of latitude where the equatorial, tropics and arctic circles are, and their significance to the seasons.
So all those lines on the globe have seasonal significance, and the seasons are simply due to the fact that the axis the earth rotates is tilted, and not in the same plane as the orbit around the sun. Funky stuff.
Also tonight: In addition to the winter solstice, and the approaching lengthening of daylight, we have an historic conjunction of Jupiter and Saturn! Go look - it should be amazing!
EDIT: Totally missed the conjunction due to overcast conditions. Nothing new! I've never seen northern lights yet, even though they've appeared several times. This has been due to wildfire smoke, overcast skies, work schedule (the power plant is quite well lit), and a full moon. Someday I may have to travel to Norway to see them, because something never fails to obscure the view.
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