Pi Day

Happy Pi Day!


Enjoy  some Pi-ku.

Solar 4: System Complete

[This is the fourth in a series of articles describing installation of a solar hot water system.]

System Start

The plumbing is all connected and leak-free. Now let’s put coolant in the system and see if we get heat! Ordinarily we might use equal parts propylene glycol (not the more poisonous ethylene glycol) and water, about 4 gallons in all. However, we turned this system on in early autumn with no freezing nights possible, so we use tap water in the coolant loop. Once we gain confidence in the system we can refill with glycol/water mixture after a few days.

First we connect a hose from a nearby faucet to the upper boiler drain valve, and another hose from the lower boiler drain valve to a drainage area out in the yard. We run the water for several minutes to flush out any flux and solder and other junk from the coolant loop.

Now we connect two short hoses, actually “washing machine hoses”, to a drill-powered pump and large bucket like so:

Following the directions in The article in Home Power magazine “DWHW Installation Basics Part 2” from June 2003 we run the pump with both valves open, and keep running until no air bubbles appear in the bucket. Then slowly close the lower valve and keep pumping until the pressure in the coolant loop reads about 20 PSI, then close the upper valve.

We keep the bucket and hoses and pump together as a dedicated kit for possible future maintenance.

One final task is to connect the pump to the PV panel on the roof. (We angle this panel a bit West of direct South, so in winter the solar water panel has a chance to warm up before sun hits the PV panel and starts the pump starts circulating. Otherwise cold coolant from the panel might cool the water in the storage tank enough to cause the auxiliary electric water heater to turn on each winter morning.)

With the pump running, take a trip to the roof to purge any air from the coin vent. Be careful: hot coolant might spray out and scald if you turn the vent valve too far too fast.

With the pump running, we feel the pipes in the heat-exchange loop get warm, and then hot. I expected  the storage tank to take several days to heat, but hot showers were available after only one-half day of system operation.

Later we insulate the pipes exposed on the roof, secured with wire-ties. These pipes might get too hot for the insulation used to insulate regular home hot water plumbing; we used insulation rated for this temperature sold by our solar heating supply vendor.

Go back onto the roof in a day or so and purge any air from the coin vent that might have collected.

Lessons Learned

  1. We would change the placement of the mounting board with pump and expansion tank to be more accessible for later repairs: lower and not as far in the corner. This is in an area where people pass by frequently and I thought the equipment would get in the way, but there was enough room.
  2. We would change the routing of the pipes going to and from the storage tank heat exchanger to first turn towards the wall and then make a right angle bend up to the mounting board. Once reaching the wall the pipes could be fastened with clamps for better support.
  3. We would attach components to the mounting board prior to attaching the board to the wall. We would follow more closely the example shown in “DWHW Installation Basics Part 2”, Home Power Magazine.
  4. Too many trips to the big-box home store for extra pipe fittings was caused by not carefully sketching in detail the plumbing for the entire coolant loop system, indicating every single fitting required– and then buying a few extra for last-minute changes.
  5. We added temperature gauges at both the inlet and outlet of the heat exchanger. In practice the difference in temperature is very small almost all the time. The heat exchanger relies on many trips around the coolant loop to get enough heat transfer to the storage tank.
  6. We learned this project is indeed possible for someone with a technical bent and little experience. If you have ever dabbled in car repair or significant home repair project then this is well within your grasp– at least if you have a flat roof.
  7. Our solar storage tank includes an auxiliary electric heater. If we had hooked up this electrical connection just after connecting the hot and cold water pipes, we would not need to be in a hurry to complete the coolant loop connections.

Regular Operation

Here is a graph from our gas bill in winter.

See how much less gas we burn than last year? We are now paying much more for “access fee”, taxes, and fees than per/therm gas usage. If we could stop using natural gas for the stove and clothes dryer, we could unhook from the utility. We really like a gas range, but propane might do. We have ideas about the clothes dryer that might appear in a later post.

After running for several months, we are encountering no problems. It just works!

During winter months we do encounter winter storms with several consecutive days of no sun, and then the auxiliary electric heating element in the storage tank does turn on. During non-winter months we can turn off electricity to the tank altogether.

Our March magnetic drive DC circulating pump might tend to be noisier than other type pumps, according to Home Power November 2007 article “Pick the Right Pump“. We live in a quiet neighborhood, and my office is located not far from the pump, and my personal preferences tolerate very little ambient noise. Our noise- meter measured 53dB at a distance of one meter during regular operation, not much louder than our refrigerator when the compressor is running. Somewhat more noticeable is the variation in pitch of the pump during semi-cloudy days, but nothing too objectionable.


What will it take for solar hot water system panels and other system components to be sold in big-box home-improvement stores? Should light-weight solar thermal panels be used, or heavier but very durable panels such as ours? Should flexible copper tubing be used to ease the process of installation, or some sort of temperature-resistant plastic pipe? What diameter tubing still gives reasonable coolant flow and heat transfer? What components can sold in pre-assembled form for faster and easier installation? We welcome your thoughts.

Related Posts: Solar 1, Solar 2, Solar 3

Random Friday: What We Have Read 8

From my reading journal. We haven’t posted from the r-j for a while, so will catch up over the next few weeks.

Fortune’s Formula
William Poundstone

John Kelly at Bell Labs develops a strategy of risk management, applied at blackjack by MIT mathematician Edward O Thorp. Later he applies the same concept to hedge fund Princeton-Newport. A colorful cast of characters appear and re-appear like a Stephenson novel: Claude Shannon, Rudy Giulani, Michael Milken, Warren Buffet, mobsters, Wall Street inside trader Ivan Boesky, LTCM, and more. Truth really is stranger than fiction in this lively twisted story. Highly cogent and revelatory.

The Numbers Behind Numb3rs
Keith Devlin, Gary Lorden

Did you ever suspect the mathematical basis of the CBS crime show “Numb3rs” was occasionally bogus? Certainly not, according to Devlin (NPR “Math Guy”) and Gary Lorden (show math consultant). We are introduced to graph theory of social networks of terrorists, distance functions in multi-variables that include eye color and hair length, applications of wavelets for fingerprints, and a host of other real-world applications.

Of particular note is the CAPPS analysis in the “Prisoner’s Dilemma” chapter. Two MIT grad students analyze the system for selecting passengers for screening before airline flights. Since the terrorists are free to conduct multiple dry runs, the students show that any screening system can do little better than random chance.

The Sharing Knife: Passage
Lois McMaster Bujold

Dag and his young bride Fawn are no longer welcome at Hickory Lake Camp, having violated the taboo of relations between Lakewalkers and farmers. The pair decide to travel among normals, spreading the word about “blight” areas caused by “malices”, so farmers can better avoid the dangerous places and avoid capture by the deadly creatures. The pair decide to take passage down the river, accompanied by Fawn’s brother Whit, where they meet a young riverboat captain searching for her father and fiance. Join the group on a wonderfully drawn journey on the river.

Neil Gaiman

Many characters from Marvel are placed in 1602, with Queen Elizabeth’s rein fated to end, succeeded by James in Scotland. Sir Nicholas Fury is spymaster, Doctor Strange is mystical advisor to the Queen, Matthew Murdock is a blind troubador with a secret life, and so on. Several characters are better disguised from the reader, and it may take a few hints before you place the character with the familiar superhero/villain.

Several mutants are tolerated in the realm by the Queen, but are likely to be persecuted by James, with a suspicious alliance with the Inquisition.

Great fun with the Marvel mythological universe. The writer is even able to plausibly explain the appearance of these characters from the future into an earlier time.

The Yiddish Policemen’s Union
Michael Chabon

After the defeat of Israel in 1948, millions of Jewish refugees live in the temporary federal district of Sitka, Alaska, now only two months from reversion back to state control. Homicide detective and barely-functioning alcoholic Meyer Landsman discovers a body in the same cheap hotel where he lives, and investigates with partner Berko Shemets. We enter a gritty vibrant world of refugees, gangsters, spies, and fanatics, utterly engrossing.

World War Z
Max Brooks

The Zombie War is told as oral history by multiple individuals, describing the rapid collapse of civilization across the world (accelerated by initial secrecy and denial by governments), isolated hold-outs, massive refugee movement to islands, and eventual struggle to take back the world. The book reads as a novel composed of short stories.

The beginning stories are set in varied locations such as Greater Chongqing, Barbados, and Meteora, Greece, drawn with detail adding to the sense of authenticity. Characters are allowed to tell their own stories in their own words, particularly effective in capturing the sense of defeat and desperate struggle in the early stages.

The Man with the Golden Torc
Simon R Green

Eddie Drood (told as first-person) is part of the highly secretive Drood clan that has quietly protected the world from demons, evil geniuses, monsters, and assorted magical beings for generations Each Drood is equipped with a torc that expands to full-body-armor loaded with features. Eddie is on the outs with his family, falsely accused, and must join fate with a witch to uncover secrets and clear his name. Each page reveals some new magical being or artifact or plot twist for a many-layered action-filled ride.

The Ten Most Beautiful Experiments
George Johnson

Today published scientific experiments might list a hundred collaborators, but back in the early days of science, a few particularly elegant demonstrations were accomplished by a lone individual, and are capable of being understood by non-scientist reader how the results are significant. Michelson’s measurement of the speed of light, Newton and his elegant experiment with prisms on the nature of color, Pavlov’s salivating dog, and Millikan’s cloud chamber for measuring the charge of an electron are among the experiments included here.

You might quibble about the choice of experiments, but that is a good thing– we techies should all give thought to our own top ten list. The writer does a fine job in explaining the historical context for each experiment, allowing us to understand why each result is so important as to be worth remembering.

This reader would like to see a web site or wiki to accompany the book, to allow the reader to reproduce these experiments (perhaps not Pavlov’s) and see photos of working equipment.

Grammar Snobs Are Great Big Meanies
June Casagrande

This former copy editor and word enthusiast skewers well known grammar authorities such as Chicago Manual of Style, William Safire, and Associated Press Stylebook, by noting their lack of agreement on key word issues. She uses this as a hook to keep the reader entertained while providing a refresher in grammar concepts underlying particular questions of word usage.

Farewell, My Subaru
Doug Fine

Join the journalist as he moves to a remote ranch in southern New Mexico with the goals of living sustainably and locally without giving up key perks such as Netflix and Internet. With considerable wit and energy he documents acquiring goats (escape artists with fur), adding solar panels, converting his truck to burn veggie oil, and growing a vegetable garden. With each adventure he frankly relates mistakes made, so we can learn from his efforts and try these projects ourselves. This reader can hope for a sequel.

The Fortune Cookie Chronicles
Jennifer Lee

The writer explores the world of Chinese restaurants in America, so much unlike traditional food in China, where fortune cookies, chow mein, and egg foo yung, and General Tso’s chicken is unknown. Using the story of the fortune cookie as a foundation, each chapter covers some aspect of this world, including the mass migration of Chinese workers from the province of Fuzhou, take-out boxes, soy sauce (with no soy), Kosher Chinese scandal in DC area, delivery menu wars in Manhattan. Intelligent and lively, this book is a delight for foodies.

Rolling Thunder
John Varley

In previous books Mars had thwarted a sneak attack from powerful interests on Earth, and now has space supremacy with exclusive control of the squeezer propulsion device invented by shy genius Jubal. Podkayne, third generation from one of the first families on Mars, is starting her mandatory military service, lead singer in a small band, part of the entertainment division of the Martian Navy. On a visit to an outpost on Europa, the ground shifts under Poddy, and life gets interesting real fast.

Homage to  Heinlein juvenile fic, this novel is fun and stands on its own. A young person, not yet beaten down by The Man and The System, discovers hidden strengths, nobility of spirit, and fame and success beyond any expectation.

The Lady Tasting Tea
David Salsburg

The development and application of statistics in the twentieth century is traced, by telling the lives of key mathematicians involved and the particular problems they were trying to solve. We start with Galton and the journal Biometrika, Pearson and his skew measurements, Gosset’s measurement of brewing beer, Fisher and “Statistical Methods for Research Workers”, Jerzy Neyman and hypothesis testing, Cornfield and economics modeling, and so on. Many personal anecdotes are related. No equations appear to scare readers, but key statistics concepts are explained with enviable clarity lacking in many textbooks.

The Man in the High Castle
Philip K Dick

Germany and Japan have won the war. Childan lives in the Japan-controlled Rocky Mountain States, selling fake historical American artifacts to wealthy Japanese collectors. Mr. Tagomi, an official in the Japanese embassy in San Francisco, undertakes to guide Childran subtly without the reciprocal social obligations overt advice would entail in Japanese culture. Frank Frink is an artisan intent on creating something new and American, and approaches Childran to sell his creations. Frink’s ex-wife Juliana goes to see the author of Grasshopper, a banned book describing an alternate history where the Axis powers lost the war. Several characters use the I-Ching for advice, and become intertwined. With superior rocket technology, Germany has gone to the moon much earlier than our history, electronics lags far behind, and Germany faces succession struggles and potential conflict with Japan.

Golden Compass
Philip Pullman

After listening to the audio book and seeing the movie, we were glad to finally read the book.

Undercover Economist
Tim Harford

Similar to the style of Freakonomics, this Financial Times Magazine columnist and blogger/columnist for Slate uses economic theory to explain why Starbucks has so many choices, why popcorn costs so much in movie theaters and other questions for the individual, and then moves to issues for larger organizations such as how to structure an auction for wireless spectrum, health care, and development in China. You may disagree with his view on sweatshops or globalization, but be prepared to gain insights to the workings of the economy affecting us all.

Heart of Whitenesse
Howard Waldrop

Another collection of short stories by the creative eccentric, filled with obscure cultural references to challenge the reader. Begin by reading the afterwords first, then read the story with Google nearby, and don’t miss the “Explication and Glossary” at the end of “The Other Real World” while reading that story of the Cold War. “D=RxT” is an existential James Dean style tale of pedal car racing.

The Accidental Time Machine
Joe Haldeman

Matt is a a failed grad student with no social life, toiling long hours and barely clinging to a job as technician in an MIT lab, when he accidentally builds a time machine that seems to only move forward in time with increasingly large time intervals. With visions of fame and fortune he experiments on himself, beginning a series of challenges beginning with felony charges and growing exponentially more difficult.

Similar structure to Forever War.

The Spiderwick Chronicles: The Field Guide
Tony DiTerlizzi and Holly Black

Twins Jared and Simon and older sister Mallory move to an ancient family home, find a secret room and secret journal and secret creatures. Much shorter than a Hogwarts novel, charming, with effective illustrations, this is a good start to a new series.

Black Bodies and Quantum Cats
Jennifer Ouellette

A series of essays of science history in chronological order, including several technology developments such as Velcro, Reddi-Wip, and roller coasters not often found in similar collections. The writer delights in citing modern cultural references, such as a plot point in movie “Addams Family Values” when discussing gravity and the laws of motion.

Moon Flights
Elizabeth Moon

Short stories include several of the Ladies Aid & Armor Society, one Vatta trading tale, and various sword and military plots. Most memorable is “Tradition”, an alternate history story of Admiral Christopher Cradock’s pursuit of German ships in the Med (as opposed to actual engagement off Chile).

Unlike many collections of short stories, these include no introduction or postscript.

Born Standing Up
Steve Martin

This memoir of comedian Steve Martin’s arc from rope tricks at Disneyland and vaudeville at Knott’s Berry Farm to runaway comic success appearing before thousands of screaming fans night after night, succeeds in presenting a sober account of years of striving and a healthy amount of lucky timing ultimately resulting in unexpected wondrous success. Photos and documents add extra spice.

The Rejection Collection vol 2: Cream of the Crap
editied by Matthew Diffee

This second volume of cartoons rejected by the New Yorker (specifically cartoon editor Bob Mankoff) includes for each cartoonist a one-page photo spread, two pages of questionnaire creatively answered, and sadly only three to five cartoons one per page. While we appreciate the large format reproduction of cartoons, we are hungry for more.

The Logic of Life
Tim Harford

The writer of the Undercover Economist blog explores the rational economics explanation for seemingly illogical situations: racism, stubborn pockets of poverty in cities, highly paid CEOs. Game theory as applied to economics is used to explore the dating scene and poker competition. Lively and lucid, much in the style of Freakonomics.

Iron Kissed
Patricia Briggs

Mercy Thompson book 3.

Blood Bound
Patricia Briggs

In Moon Called, Mercedes Thompson needs a favor from vampire friend Stefan, and he has come to ask her help in return, as a secret witness when he meets another. What can be more evil than a vampire or even sorcerer: combo plate. The vampires play a deep and subtle game, and vamp leader Marsilia believes Mercedes poses a special threat to her kind.

Moon Called
Patricia Briggs

Mercedes Thompson, VW mechanic trained by an ancient fae, is a coyote shape-shifter with native-American heritage, raised by a clan of werewolves. Werewolf packs are complex, with dominance politics of wolves blended with human instincts. She becomes deeply involved with the local were pack after a surprise attack.

Breath and Bone
Carol Berg

How to Buy, Sells, and Profit on eBay
Adam Ginsberg

Explains the basics of running an eBay-based business, with many ideas for items to sale, and an enthusiasm which will spur the reader to overcome doubts and take first steps.

Embroideries (graphic novels)
Marjane Satrapi

After lunch, the men go off to nap while the women clean up and gather around the samovar for tea and talk. Hear the stories of these individuals as they talk about their sex lives. Arranged marriages, virginity and faking, old men after young girls, satisfaction and frustration. A remarkable blend of humor and revelation.

Moon Called
Patricia Briggs

Mercy Thompson is a shape-shifting coyote caught up in deadly struggle among werewolves.

Orange Cheeks
Jay O’Callahan, illustrated by Patricia Raine (children)

Four and a half year old Willie loves to visit Grandma in Cambridge, and he was trying his best to be extra good. In spite of his best efforts he gets into trouble– what will happen?

Told by a master story-teller.

Things Will Never Be the Same
Howard Waldrop

Waldrop researches obscure subjects in depth, and then writes unique short stories which are real gems. My favorite in this collection is “Wild, Wild Horses”, about a special equine in ancient Rome.

Benjamin Franklin’s Numbers
Paul C Pasles

Benjamin Franklin is recognized for many key contributions in science, but not so much in mathematics, aside from some magic squares mentioned in his autobiography. The writer explores the mathematical side of Franklin, from his paper on population growth that influenced Malthus, to problems included in Poor Richard’s Almanac, to his moral algebra claimed to influence the utilitarianism of Bentham. Pasles does a neat bit of historical research to find improved magic squares created by Franklin overlooked for generations, and explores the many wonderful symmetries of his magic squares and magic circles, and delves into how they were created.

Persepolis 2
Marjane Satrapi

The author escapes the turmoil of Iran to become a student in Austria in 1984. Without family and friends near, she must work out living arrangements and find friends among people of very different backgrounds than her own. She finds some kindness, but also false friends that ultimately cause great harm. After a particularly bad episode she returns to Iran, and discovers how her brief experience in the West creates a chasm with family and friends.

Three Men in a Boat
Jerome K Jerome

A tale of three buffoons on a trip up the Thames written with a dry elegant turn of phrase, with many flashbacks and twisty turns of narration. Must inevitably be compared with Wodehouse today.

Crooked Little Vein
Warren Ellis

Michael McGill, barely surviving as a Manhattan detective and bad luck magnet, is approached by the Chief of Staff to the President to obtain a Constitution written in secret by founding fathers, which will grant special powers to the owner. Accompanied by Trix, a doctoral student of kinkiness, McGill journeys from one depraved character to another in search of his goal.

Funny, snort-whiskey-out-the-nose hilarity in places, a commentary on alternative lifestyles and so-called majorities. Echoes of Hunter S Thompson.

Privilege of the Sword
Ellen Kushner

Alec, now Duke Tremontaine, avoids appearance of politics like his mentor the late Duchess, adopting a public air of decadence and unpredictable behavior earning the appellation Mad Duke. He secretly thwarts Lord Ferris and other foes with a plentitude of schemes. The Duke arranges his niece Katherine to be trained in the sword and take her place in society uniquely prepared to defend her own honor, unlike her friend Lady Artemesia who must rely upon family.

Fires of the Faithful
Naomi Kritzer

Eliana studies violin at a music conservatory, sheltered from the conflicts resulting from the Circle imposing a new religion, violently suppressing any traces of the old. When she discovers a terrible secret about the mage abilities available in small part to anyone, and concentrated in certain powerful individuals, she embarks on a path that holds many perils.

The Good Husband of Zebra Drive
Alexander McCall Smith

Mma Ramotswe’s husband Mr JLB Matekoni investigates his own case, Mma Makutsi has a falling-out with her employer, and the investigator resolves a case at a hospital by using mercy.

The Dord, the Diglot, and an Avocado or Two
Anu Garg

Light-hearted tour of nifty words. Chapters include words derived from Dickens novels, people, and myths. Humor is key. Scattered throughout are word-related riddles: “What is the longest word that doesn’t repeat a letter?”

Garrison Keillor

Keillor expands his familiar pontoon tale into a full novel. When Evelyn dies, her will specifies her ashes should be placed in a bowling ball and dropped in the middle of Lake Wobegon. Her daughter Barbara is determined to honor her wishes, setting the stage for an eventful day.

We were delighted to hear a shorter version of the story at a fundraising show at Popejoy: thirty minute monolog, no notes, no teleprompter, just Garrison’s deep voice.

Flesh and Spirit
Carol Berg

Valen is a pureblood mage, with a learning disorder misunderstood by his imperious family, causing him to escape and hide for years disguised as a normal.

The Thief youth fic
Megan Whalen Turner

Gen is a young thief languishing in prison, until the King’s magus has him released for a secret mission to steal an ancient treasure linked to the fate of nations. The magus and Gen journey with Pol, faithful experienced professional soldier, his charge Saphos, and the mage’s student Ambiades.

Gen is mouthy and proud, appealing to a young reader, and in a surprise twist we discover all is not as it appears.

Rudy Rucker

Jeff Luty wants to convert the matter of Earth into “nants”, running a simulation of virtual Earth. He is thwarted by Ond Lutter, who deploys an ophid mesh network every few mm apart, which allows a ubiquitous network and enhances abilities of the individual. Everything changes. The singularity causes unforeseen side-effects, such as the discovery of a parallel universe, or brane, some of whose inhabitants have been secretly traveling to our Earth. Teleportation and ophid spam and emergent intelligences also arise. A band of homeless young counter-culture drifters, the Big Pig Posse, including meta-novelist Thuy, amateur physicist Jayjay, and physics gamer Sonic, get drawn into the center of action to thwart Luty’s plans to hack the orphidnet and release his nants.

Major characters in Rucker novels tend towards precipitous actions, unrequited loves, self-destructive behavior, at the expense of in-depth characterization with subtle nuance. Sometimes one notices the writer’s puppet strings. Big original ideas make this a must-read in spite of character quirks.

The Sandbox
Intro by G B Trudeau, edited by David Stanford

Collects some of the best USA soldier mil-blog entries of the Iraq and Afghan conflicts.

Marjane Satrapi

Deeply personal memoir of a teenager growing up during the Iranian Revolution of early 1980s. The stories of friends and family bring the vast events into proximity, telling of Ramin in school whose father worked for the Savak, two friends of the family released from the Shah’s prisons only to be persecuted by revolutionaries, her own encounter with the Guardians of the Revolution, Women’s Branch, after buying bootleg rock cassettes. The powerful conclusion to this set of stories will stay with reader.

Black and white illustrations are remarkably effective, with clean minimalist form, almost iconic, good use of white lines on black, crowd scenes often using tiled images with a nod to ancient Islamic art.

Alcatraz versus the Evil Librarians
Brandon Sanderson

Drifting through various foster homes, Alcatraz Smedry discovers on his thirteenth birthday that he is a powerful occulator, and that he really lives in Hushland controlled by an organization of tyrannical librarians intent on keeping the truth from citizens. With Grandpa Smedry and young warrior Bastille, Alcatraz takes on the Dark Occulator.

Similar to Series of Unfortunate Events.

Empire of Ivory
Naomi Novik

Captain Laurence and his dragon Temeraire must travel to a distant colony in search of a cure for an illness incapacitating all British dragons, before Napoleon discovers the island is undefended by air. They discover why no explorer has returned from the heart of Africa. Finally, the duo must make a difficult choice between country and dragonkind.

Reads very much like the Master and Commander series.

The End of America
Naomi Wolf

Democracy has a “failure-mode” (my term) to a fascist shift to a closed society. Ten steps for a fascist shift include:

  • Invoke an external and internal threat,
  • establish secret prisons,
  • develop a paramilitary force,
  • surveil ordinary citizens,
  • infiltrate citizens groups,
  • arbitrarily detain and release citizens,
  • target key individuals,
  • restrict the press,
  • cast criticism as “espionage” and dissent as “treason”,
  • subvert the rule of law.

The writer explores this process in a historical context, particularly Germany in 1930s and Italy in 1920s, and gives many examples how the Bush administration is using the same tactics, often with hauntingly similar rhetoric.

The Quitter
Harvey Pekar, art by Dean Haspiel

A working-class Jewish kid in Cleveland stumbles through life, alternating between insecurity and goofing off and angry outbursts, floating from job to crummy job. Finally Pekar understands his mind works differently from others, and lands a stable if unchallenging job, giving him time to pursue writing. Gritty, honest, real.

Related Posts: What We Have Read 7, 6, 5, 4

Analog TV Transition News

[Wow, all links are dead, and therefore deleted. Why forget so much, Internet?]

Related Posts: Requiem For Analog TV, Lurching Toward Digital

More Sagebrush

  • February 24, 2009
  • General

So need more “Sagebrush” blogs?

  • The Sagebrush Variety Show, audio theater with political satire and commentary
  • The Nevada Sagebrush, student voice of University of Nevada, Reno
  • Parsley & Sagebrush Band, bluegrass combo
  • Sagebrush & Serendipity, personal blog of artemisia
  • Sagebrush Wisdom, “common sense thoughts from the country”
  • Sagebrush Valentine, 6 artists with 1 title create 6 songs in 1 hour
  • Sagebrush Strokes, Nevada landscape prints online store
  • The Sage Brush from Montana, a memoir of a youngster studying art with western muralist Bernard Preston Thomas.
  • Sagebrush Spinoni, puppy pictures from a dog breeder.
  • Sagebrush Bob, political diary on dKos.

Related Post: Hello, World!

Requiem for Analog TV

Noted author Bruce Sterling presents a eulogy for analog TV, at the Berkeley Art Museum, February 17 2009.

[flash] [video link]

kudos boingboing

Previously: Analog TV Shutdown Delayed, Lurching Toward Digital, Switching to Digital TV

Solar 3: Connecting

[This is the third in a series of articles describing installation of a solar hot water system.]

With the panel now securely mounted on the roof, we can turn our attention to plumbing. With an electronics background, I have done plenty of soldering– but only wires, not copper pipe. YouTube has several videos demonstrating the procedure, so it is time to get some pipe and practice “sweating”…


Time to “tool up” for the job:

From the top and counter-clockwise: propane torch, teflon tape and pipe dope (more on that below), lead-free solder, 4-in-1 cleaning brush (for removing oxide from 1/2″ and 3/4″ copper tube and fittings), flux with brush, and pipe cutter. Not shown but also recommended are leather work gloves and a bench vise.

We want to avoid as much down-time for hot water availability as possible: teenagers getting ready for school in the morning are not particularly open minded about the advantages of solar energy when they are taking a cold shower. Without disconnecting the current system I could start on the roof and connect the solar panel with pipe near to where the pipe will pass through the roof to turn down towards the storage tank.

Our panel has four connecting ports, two on top and two on bottom. One top port is used for coolant output, and the other can be connected to another panel– not necessary in this installation.

We used the extra top port to connect a pressure relief valve and a coin vent used to purge air bubbles from the coolant loop, which should be installed at the highest point in the system.

Since the solar panel might someday have to be temporarily removed when our tar and gravel flat roof is redone, we installed unions at the top and bottom ports.

After roof work, I soldered several sub-assemblies of parts together, to make final assembly go faster. Several parts, such as boiler drain valves, pump, and gauges, had pipe threads and required solder-to-pipe adapter fittings.

I tested sub-assemblies when possible, using a collection of threaded end-caps and a Schrader valve adapter. I built the adapter using a Schrader valve stem (from an auto parts store), a brass 1/4″ female to 1/2″ male threaded adapter, and a small quantity of JB Weld metal epoxy. The brass adapter is not sized to thread with the valve stem, and relies on epoxy to seal and hold the parts together.

Here is the gadget in action, testing a sub-assembly.

Pressure testing showed no leaks on solder joints, but revealed several leaking threaded joints. Searching the web, we ended up using three layers of yellow (not the thinner white) teflon tape on a male pipe thread, and on top of that brushing on a modest coating of RectorSeal TPlus2 pipe joint compound. Problem solved.

The plan is to remove the old water heater and replace with the solar storage tank on Friday, after the dread teenagers have left for school. My goal is to get cold water back by the end of Friday, finish connecting the coolant loop by end of Saturday, and fill coolant Sunday morning to begin heating water. A professional could work much faster, but I wanted to be methodical, and expected to take breaks to ponder any problems.

Behold our old gas water heater.

In addition to the hot and cold water connections, you will observe the required pressure relief valve and pipe, as well as some other  devices particular to our installation: a pressure limit switch on the cold water line for our water pump, and a valve connecting to 1/4″ copper tubing supplying water to an evaporative cooler. Our new installation will try to “neaten up” this extra hardware.

After turning off the gas supply to the water heater, I turn off the water supply, drain any extra water in the lines, unscrew the hot and cold supply to the tank, cut the soldered pressure relief line, and remove the exhaust vent. The hole in the roof for the exhaust vent will make a handy pipe run (passageway) for the coolant loop going to and from the solar panel. After connecting a hose to the tank drain valve, I let the tank empty and moved it out of the way.

Before putting in the new tank, I attached a plywood mounting panel to studs in the wall with lag bolts. (With hind-sight, I would have mounted the pump-gauges-and-expansion-tank assembly to the panel beforehand, and would mount the panel lower for improved accessibiilty. More on woulda-shouldas in Part 4 of this series.)

I rolled in the new tank and made connections for hot, cold, pressure relief, and the extra bits mentioned above. All threaded connections used the tape and pipe dope combination mentioned previously. I added a anti-scald mixing valve sub-assembly to prevent scalding in case water in the storage tank got hotter than a normal water heater.

Notice I added thermometers at both the input and output to the mixing valve, which is overkill. The mixing valve requires an extra connection between hot and cold lines, making the connections look more complicated.

See the aluminum foil? I placed that on tank and sometimes walls to shield parts from solder drops and heat.

After turning on water, I was delighted to find no leaks! After a well-deserved break it is time to complete the coolant loop.

I fastened the expansion tank and coolant circulation pump to the mounting board with metal plumber strap, after cushioning between the board and parts with foam rubber to reduce vibration. Unions were used for the pipe runs up to the roof, to make it easier to disconnect for servicing. I thought about adding unions to make it easy to remove the pump– the most likely part to fail after decades of service.  Too many unions have aesthetic and reliability issues, so I plan to cut and solder for pump replacement.

With everything connected in the coolant loop, it is time to pressure test.

I used a bog-standard bicycle pump with integrated gauge, and pressured up to 10PSI. Sadly, the pressure did not hold, so soap solution was applied to solder joints and threaded joints until a leak was identified:

This was one of the last solder connections made, so perhaps I was in too much of a hurry or too complacent. After using wire brush and flux on the pipe and fitting, I did have to let this joint wait for several minutes before sweating. Perhaps this time delay was also a factor. Re-heating and applying more solder did fix the leak.

I pumped the pressure up to 20PSI and discovered another leak that did not leak at 10PSI. This leak would not close with more heat and solder, so I actually had to cut out the leaky fitting and try again with fresh clean parts. Rather than be discouraged, by this time I was getting quite comfortable with cutting pipe and soldering, and glad to be able to take time to do the job right.

After fixing the two leaks, the coolant loop held air at 20PSI for hours with no noticeable loss, so the system is ready to add coolant. I wanted to do that in the morning before the sun is up to begin heating the panel. More on that in Part 4 of this series.

Related Posts: Solar 1, Solar 2

Analog TV Shutdown Delayed

US Congress approved a delay from the planned February 17 shutdown of broadcast analog TV signals to a new deadline of June 12. The President is expected to sign the measure into law. From the Washington Post:

The Federal Communications Commission has said that centers set up to answer consumer questions about the conversion were understaffed and that the government needed more time.


“There’s no way we could have accomplished in the next 14 days what should have been done over the past 24 months,” said Michael J. Copps, acting FCC chairman.

The $40 coupon program for assisting citizens in purchasing digital TV converter boxes for their old analog TV sets (and computer analog TV tuners) is out of money. Additional money might be included in the stimulus package now under consideration.

Cable and satellite TV subscribers can keep using their old TVs. Here in New Mexico, many rural areas are served by lower power translator stations that might continue broadcasting analog for months and years past the June shutdown date.

Previous Posts: Lurching Toward Digital, Switching to Digital TV

WIFI Theremin

Midnight Research Labs describes a nifty theremin hack implemented by detecting signal strength of a WIFI signal. Python source is available to examine.

link [kudos HackADay]

Bonus Hack: Zevv implements an ultrasonic theremin, emitting ultrasonic chirps from laptop speakers,  detecting reflection to the microphone, and driving a tone generator.

Random Friday: What We Hike 3

Pix from neighborhood of Dog Canyon in southern New Mexico, 2008.

Related Posts: What We Hike 2, What We Hike