Wednesday, January 19, 2005


You wouldn't think so at first, but heating your house can be a very big deal in New Orleans. I'm sure our getting down to freezing at night earns no sympathy whatsoever to anyone reading this, for nearly everywhere else in the country is colder than we are. But you have insulation. We don't. None whatsoever.

The old house we are renting part of has walls constructed of an inner layer of plaster over some thin slats nailed to wooden uprights, faced with clapboard. Nothing but air in the middle. I could probably figure out the insulative R-value if I felt like it, but it's not much. The house itself is built up about a yard high on brick pylons (it floods here) and so air is free to flow underneath our wooden, uninsulated floor as well.

When we first moved in, there was but one small gas wall heater in one of the rooms, and nothing else in the rest of the apartment. Our first winter when it dropped to around freezing or below, you could see your breath in the bathroom in the morning. This was after I'd gone around with a stick of incense, plugging up air leaks with duct tape or spray foam, including a huge eleven foot high, two inch wide gap between the chimney and the wall where air flowed in freely. I've been much, much warmer in 40 below weather in a lightly-insulated house up north with proper heating.

Since then, we've purchased an electric space heater, a little bathroom heater, and when the landlord replaced the air conditioner last Spring, she bought one which also included a heater, so Winter isn't quite as miserable. But, realisticly, the electric heaters don't do nearly as much as the gas unit and use a lot of energy. The gas heat began to work erraticly the first day of the projected coldest week of the year. Most people would have immediately called the landlord, but she'd made noises about removing the gas unit now that we had an electric one, but appeared to have forgotted about it. She pays gas, we pay electric, so I was loath to remind her of its existence.

It would operate for a while, then go off suddenly. You couldn't re-light the pilot light until it had sat idle for a while. If you turned it up to the highest setting, with three panels fired, it would shut off within minutes. Leaving only two going let it stay lit for at most an hour at a time, but the decrease in heating power by a third was very noticable. It couldn't really keep up at full power with falling temperatures and air-leaks in the old construction.

Last night was exhausting. I had to wake up every hour or so and re-light the damn thing. I learned new appreciation for ancestors who lived with small wood stoves or fireplaces which had to be re-banked regularly during the night if one didn't want to freeze to death. I don't mean to really compare our situation to theirs, as we weren't in any real danger, but the similarity did occur to me.

During the light of day, I was able to dig around on the net to find some pages about gas heater troubleshooting, and got a decent idea about the possible causes for its erratic behavior even if I couldn't find info about our specific model. I guessed that it was a thermocouple sending a wrong signal, causing the gas safety valve to shut off the flow. Or maybe the thermocouple was working perfectly, and the unit needed to be shut off so it wouldn't start a fire or poison us with carbon monoxide?

Was the thermocouple getting too much heat, or too little? How to figure this out without blowing myself up or suffocating us in our sleep. Not that the latter was much danger in our leaky place, but still...

I finally got a clue in one of the many web pages I consulted, which mentioned a yellow colored pilot light being a sign of poor gas flow through the pilot nozzle. This would make the thermocouple attached to the shutoff valve think that the flame had gone out, shutting off the gas flow so as not to poison us and create a fire hazard.

Our pilot light was yellow, slightly more yellow than I remember, I think, but I never gave it much thought before, honestly. And the flame wasn't toucing the thermocouple, but barlely missed it if you looked closely from the right angle. Aha! A little work with an eyelash brush supplied by Lady M____, some cleaning out of dust buildup inside the unit, and.... the pilot was a beautiful shade of blue and struck the thermocouple dead on... and it's still going several hours later at full blast. *relief*

And while it's not exactly warm in here, it's not exactly cold either, which is the best we can hope for in this weather. I'm tempted to sing a paen to the laws of thermodynamics, to the first law glowing orange and blue as the gas and oxygen combine in the firebricks, to the second law which allowed me to reduce the entropy in the pilot light assembly-- at the cost of increasing the universal entropy, alas. On the wonders that are radiant and convective heat transfer, and lastly to the humble but tireless diffusion whch carries the thermal energy 'round the apartment. Ahhhhh......

In a final note, let me also say that I've finally finished Neal Stephenson's Baroque Cycle. All three volumes and 2652 pages of it. I'll probably have more to say about this later, but just wanted to mention it to mark the occasion. Two nice achievements in one day.


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