Tesla road trip from New Jersey to Boston

Messages to a group chat from a friend whose daughter is a high school athlete:

  • So my daughter caught a ride today from NJ to Boston with a girl whose father had a Tesla
  • took six hours to get here
  • because they had to stop three times to charge his thing
  • “we went to get sandwiches and the dad still sat in line waiting for the charger”
  • “we had to drive sideways to some mall to the charger”
  • “the GPS said 3h50m to get to Boston, it took us six”
  • “I wanted to be funny so I asked the dad if he would recommend an electric car to us because we have old cars and it’s time to upgrade. He enthusiastically said yes”

This was not a weekend with exceptional travel demand. This was not a trip through a sparsely populated state. This was not a trip on back roads.

I’m still a Tesla fan because it is the only company with Dog Mode (see Car/Kennel from this blog in 2003). The latest Tesla 3 seems to have been restyled slightly. Here’s the 2019 version from Car and Driver:

This the latest version, perhaps available in the U.S. in 2024:

I hate to give up the space and sliding doors of the minivan, though, and I’m not sure how we would charge an electric car. We don’t keep our Honda Odyssey in the garage. We would need HOA approval to install a car charger on the exterior and I am not aware of any chargers that fit into a Spanish Colonial Revival style.

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Meet in Orlando at the big fencing tournament?

Who would like to meet in Orlando at the big fencing tournament? I expect to be in Orlando on Thursday and Friday (26 and 27). Watching the competition is free. SeaWorld and Disney may also be involved! (Those are neither free nor immune from the inflation that the government assures us does not exist.) A friend’s kids are competing. If you haven’t had your mRNA COVID-19 booster and your flu shot (prevents all flu symptoms except for hospitalization and death), you can get that mistake corrected at the same time:

What if Ron DeSantis comes down from Tallahassee and says something unkind about the 2SLGBTQQIA+ community? Just text “CRISIS” to Dr. Shannon Jolly, the Sr. Manager – Diversity, Equity, Inclusion and Belonging for USA Fencing.

Potentially confusing:

USA Fencing encourages everyone to be mindful of others’ pronouns and gender identities. When in doubt, ask politely, and use the pronouns people share with you.

In the first sentence, people are merely “encouraged”. In the second sentence, however, people are ordered to use specified pronouns. Also, what do they mean by “when in doubt”? Are they suggesting that gender identity can be inferred from surface appearance?

Please email philg@mit.edu if you want to get together!

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New York Times explores the low SAT scores of poor children

“New SAT Data Highlights the Deep Inequality at the Heart of American Education” (New York Times, October 22, 2023):

One-third of the children of the very richest families scored a 1300 or higher, while less than 5 percent of middle-class students did, according to the data, from economists at Opportunity Insights, based at Harvard. Relatively few children in the poorest families scored that high; just one in five took the test at all.

The disparity highlights the inequality at the heart of American education: Starting very early, children from rich and poor families receive vastly different educations, in and out of school, driven by differences in the amount of money and time their parents are able to invest. And in the last five decades, as the country has become more unequal by income, the gap in children’s academic achievement, as measured by test scores throughout schooling, has widened.

What are readers supposed to do with this information? SAT scores are correlated with job performance. By highlighting the dismal scores of a subset of Americans on its front page, is the NYT trying to persuade readers to avoid hiring those who grew up in poverty?

The Newspaper of Truth says that helicopter parenting is the sure path to a smart kid:

Parents have embraced what researchers call intensive parenting — the idea that parents should immerse children in constant learning. Half a century ago, rich and poor parents spent about the same amount of time with their children. Now high-income parents spend more one-on-one time with them, doing activities like reading — what Robert Putnam, the political scientist who wrote “Our Kids: The American Dream in Crisis,” calls “‘Goodnight Moon’ time.”

If true, shouldn’t the SAT scores of children from high-income families be much higher today compared to in the 1970s? The NYT cites no evidence to suggest that “Goodnight Moon” time has helped the privileged brats of today compared to 1970s kids who were left with their toys while moms socialized over gin and tonics, read their own books, had sex with neighbors (“One woman who married at 20 started an affair within a year. ”I think it’s your way of asserting that you can still act independently,” said the woman, now in her mid-30’s.” (NYT 1987)), etc. Also, aren’t the poorest parents the ones who have the most time to spend with kids? Consider what used to be called a “welfare family” whose house, health care, food, smartphone, and broadband are all paid for by taxpayers slaving away at boring jobs. The adults in that family don’t need to suffer the indignity of wage labor in order to keep a roof over their head and food on the table. The NYT does not explain what the jobless poor are doing if not spending time with their children.

One explanation that the NYT does not explore in detail: SAT performance is heritable. If rich parents had high SAT scores and the ability to score well on the SAT is heritable, it would make sense that children of the rich also have high SAT scores. One sentence is devoted to this topic: “Although the heritability of cognitive ability appears to play some role on an individual level, there is also a lot of evidence that environment matters.” There is no explanation for why heritability couldn’t play the same role on a neighborhood or city-wide level. If a neighborhood is packed with low-income parents due to everyone with a higher income having moved out, and employers in our modern economy pay for higher cognitive ability, why wouldn’t the average cognitive ability in the low-income neighborhood be low?

In a study of supernerds, it turned out that a higher SAT math score did correlate with higher income. From Insider:

The chart below compares the top (Q4) and bottom quartile (Q1) of the top 1% of performers on the SAT math section. It shows a significant difference, even among those subsets, in performance later in life (participants were surveyed at around age 33). For example, men in Q4 from one study group earn 13 percent more than those in Q1.

Note that “bottom quartile” was not the “bottom quartile” of all Americans who took the SAT, but of the top 1% supernerds. (identified at age 13).

It is surprisingly tough to find a broad study of how SAT scores from, say, 1990, correlate to 2022 income. But it makes sense that there would be a correlation. People who do well on the SAT are good at sitting at a desk, following instructions, being consistent with procedures, etc. These are exactly the capabilities that many high-paying jobs require. Some high-paying jobs, such as physician, have been explicitly limited to those who score well on standardized tests (though that may change; see “Removing the MCAT Could Improve Diversity in Medicine” (Newsweek 2023)).

Circling back to the NYT article, I find it interesting that the possibility of SAT score being heritable was not considered, even for long enough to dismiss it. Let’s also look at the solution:

The solution, researchers say, is addressing achievement gaps much earlier, through things like universal pre-K, increased funding for schools in low-income neighborhoods, and reduced residential segregation.

It could benefit all parents and students, even wealthier ones. Parenting in highly unequal societies is intense and competitive, driven by fear of the increasing risk that children will be worse off than their parents. Parenting in places with less income inequality and more public investment in families is more playful and relaxed, research shows. When the risk of falling is smaller, a college admissions test becomes less fraught.

The “increased funding for schools in low-income neighborhoods” idea seems inconsistent with a note earlier in the article that the typical state is already spending “more for students in low-income schools”. For example, Baltimore, one of the nation’s worst-performing public school systems, was spending over $17,000 per student in pre-Biden money (Fox), above the state average. Was the money effective? “At 13 Baltimore City high schools, zero students tested proficient on 2023 state math exam” (Fox).

[Note that these per-pupil spending numbers are substantially fraudulent. They don’t count capital costs, which are enormous. When $154 million is spent on a new high school (see https://www.wbaltv.com/article/building-new-lansdowne-high-school/41430553 ), that isn’t “spending”. Nor is the cost of the real estate considered. Baltimore official spending is up to about 22,000 Bidies per year per student, but it would perhaps be over 30,000 Bidies per year if these off-books costs were folded in. https://foxbaltimore.com/news/project-baltimore/baltimore-city-schools-spending-per-student-2022-enrollment-performance-kirwan-new-york-boston-washington ]

Given that the number of spaces at elite colleges is held fixed while the population expands, I would like to see an explanation for how the rich will “benefit” if their kids are out-competed for elite college admissions by the children of the poor, whose schools have been turbocharged with extra money (on top of the existing extra money mentioned in the article). Why didn’t Asian-Americans realize how much better off they were when Harvard rejected them in favor of non-Asians? (see Students for Fair Admissions v. Harvard) Are Jewish families better off now that their kids can’t get into elite schools? (“Harvard has gone from being 25% Jewish in the 1990s and 2000s to under 10% today. … Penn’s Jewish population declined from 26% in 2015 to 17% in 2021”; Tablet)

Related:

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WSJ: “Israel’s war against Hamas”

Buried in a Wall Street Journal article on what the lockdown champs of the Northeast will be paying for heat this winter…

Israel’s war against Hamas has injected fresh risk into oil markets. Traders have hurried to reposition themselves for a conflict that could embroil oil-rich, Hamas-backer Iran.

The recent fighting is not a battle within the war that the Arabs declared against the Jews in 1948 after rejecting the United Nations partition (background). Nor is the continued fighting part of a new war that was initiated by the elected government of the Palestinians (still popular with residents of Gaza) on October 7, 2023 (two weeks ago and, apparently, already forgotten). The current fighting is a war initiated by Israel for unspecified/unknown reasons. It is entirely “Israel’s war” and anyone who isn’t Israeli is a passive victim of the war.

Maybe CNN can shed some light on why Israel has attacked the mostly peaceful mostly defenseless Islamic Resistance Movement (“Hamas”)? Here’s the front page last night:

Muslims are heroically working in hospitals while Jews attack for no reason.

More from CNN last night, below. Palestinians are “refugees” and “evacuees”. They need “humanitarian relief” because a “complete siege” has been perpetrated by Israel for, apparently, no reason. These are disaster victims and had no role in creating the disaster:

(Separately, if whatever food trucked in isn’t sufficient for the entire population, won’t most or all of it go to those who carry guns and fight the enemy? In any type of wartime shortage situation, don’t soldiers always eat first? Thus, will it be fair to say that President Biden’s humanitarian aid will go directly to soldiers of the Islamic Resistance Movement and Palestinian Islamic Jihad? (also known as “terrorists”, but I reject this label for people fighting on behalf of an elected government))

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Has California succeeded where Tranheuser-Busch and Target failed?

It’s been more than a month since Governor French Laundry signed a new California bill that revoked the state’s ban on taxpayer-funded travel to the Lands of the Deplorables (26 horrible states).

Hate is now okay, in other words? Not exactly. The new bill says that California taxpayers’ money will be used to eliminate hate in the 26 bad states via advertising: “creates a new public awareness project that will consult with community leaders to promote California’s values of acceptance and inclusion of the LGBTQ+ community across the country” (press release)

The marketing geniuses behind Target and Bud Light famously failed this summer at their stated goals of getting more Americans to embrace the 2SLGBTQQIA+ lifestyle or, at least, celebrate the 2SLGBTQQIA+ lifestyle. The bureaucrats in Sacramento imagined that they will be more successful than the world’s highest-paid advertising experts.

Readers who live in formerly banned states: have you been reached by California’s public awareness project? If you were a hater, were you persuaded to stop hating?

Separately, I’m wondering if the ban revocation was timed to allow California elites to travel (on the taxpayers’ dime) to Austin, Texas for today’s Formula One race. Who’s watching the race on TV or in person? It might be fun to be a Formula One fan here in Florida if the organizers would schedule the Miami race for February or March rather than May (a time when a person should be paid to sit outdoors all afternoon, not pay $2,000 for the experience).

Separately, a Facebook friend in Maskachusetts is an attorney with a passion for Constitutional rights (which is why he continues to reside in a lockdown state?). He recently represented a woman who was attacked and ultimately sued by her wealthy suburban Boston neighbors for thoughtcrime. An excerpt from her lawsuit defense:

[one lawn sign displayed by the defendant] shows the words “PRIDEMONTH” and then the letters on each side of “PRIDEMONTH” fade out, to “PRIDEMONTH” to finally “DEMON” and on the last line, it says “Makes sense now.”

The judge was hostile to the Deplorable lady, and she told the defendant to stop sharing her political views, but ultimately couldn’t find a basis to rule in favor of the plaintiffs.

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On the effectiveness of the Anti-Defamation League

The Anti-Defamation League (ADL) claims expertise in eliminating hatred. When they started, they were experts in getting American haters to love Jews. In their own opinion, at least, they were so good at this that they expanded. Here’s just their civil rights section:

They want to make sure that low-skill Americans have plenty of competition from low-skill immigrants:

ADL fights tirelessly for immigrants and refugees seeking safety and a better life in the U.S. Through legislative advocacy, amicus briefs, and public awareness efforts, we have promoted just and humane immigration and refugee protection policies throughout the decades.

The ADL will make haters realize that #LoveWins:

ADL has long fought in the U.S. and abroad to advance LGBTQ+ equity, encouraging legislation that protects individuals’ rights and providing education resources that make schools, workplaces and communities more welcoming and inclusive.

What have we seen in the past few weeks? Muslim immigrants to the U.S., whose right to settle here was pushed by the ADL, rallying and pointing out that the Islamic Resistance Movement (“Hamas”) is not a terrorist organization, but the Israeli government and all supporters of Israel are (video). Twitter and Facebook jammed with anti-Israel content. A young woman in a hijab in NYC and her friend giving the finger to a billboard truck advocating for the return of hostages held by Hamas (video). Depending on your political point of view, you might agree with these anti-Israel positions, but I think that everyone can agree this is not what the ADL was trying to accomplish.

Maybe the ADL could be more effective with people if they would spend more time soaking up the ADL message? From the New York Post:

One of the NYU students who brazenly ripped down posters of Israeli hostages is an activist “extremely passionate about fighting racial profiling” who blamed her behavior on misplaced anger.

Yazmeen Deyhimi — a junior at the top university who once worked for the Anti-Defamation League — admitted to tearing apart banners that were plastered outside NYU’s Tisch Hall, in a shameless act that was caught on video.

“I have found it increasingly difficult to know my place as a biracial brown woman, especially during these highly volatile times,” she wrote.

According to her LinkedIn profile, Deyhimi is an advocate against Muslim bigotry and spent a summer working with the ADL as a CSC education intern when she was just 15 years old.

“After review, we can confirm that one of the participants was part of an ADL high school level summer internship in 2019,” a spokesperson for the organization told The Post.

The ADL had a whole summer to convince this young person that Jews are lovable!

If the ADL has failed spectacularly at its original mission, at least the Ministry of Truth is working effectively there:

The ADL has since taken down a blog post announcing the Long Island native as one of the 12 student leaders joining the program, describing Deyhimi as “extremely passionate about fighting racial profiling and championing gender equality.”

Does supporting Hamas impair a migrant’s claim for asylum in the U.S.? Not according to the Deplorables at the Daily Wire… “The U.S. Gov’t Hired A Pro-Hamas PLO Spokeswoman To Handle Asylum Claims”:

Speaking of Deplorable, what does Ron DeSantis have to say about the ADL’s passions for Islamic immigration and using propaganda to eliminate hatred? From Twitter:

No Gaza refugees, period.

It’s a fools errand to think we can separate a terrorist from a ‘freedom lover’ in Gaza.

Related:

  • the College Terror List, which was disappeared by the Ministries of Truth at Google, archive.org, DuckDuckGo, and all of the other righteous folks. This page contains various statements by elite college students who don’t seem to have been reached by the ADL’s message about the wonderfulness of Jews. Harvard: “We … hold the Israeli regime entirely responsible for all unfolding violence”; Stanford: “while Palestinian resistance is legal under international law, Israel’s breathtakingly violent actions are illegal collective punishment under the Geneva Convention”; Swarthmore: “Since early Saturday morning, Palestinians in Gaza and the West Bank have valiantly confronted the imperial apparatus that has constricted their livelihoods…”; George Mason: “Every Palestinian is a civilian even if they hold arms. A settler is an aggressor, a soldier, and an occupier even if they are lounging on our occupied beaches.” (preserved by Ghostarchive; the only way to find it is with the Kagi search engine (see below))
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New Yorkers write about the Florida homeowners insurance market disaster… using 100-year-old wooden houses as a typical example

Just as the weather here in Palm Beach County turned perfect (dry and highs of 75-80), friends in Maskachusetts who’ve been talking about escape send me an article from the Manhattan-based Wall Street Journal, “Home Insurance Is So High in This Florida Town, Residents Are Leaving”:

James and Laura Molinari left Chicago for a two-story stucco home in this city’s historic Flamingo Park neighborhood. The four-bedroom house was a short bridge away from Palm Beach island and walking distance to downtown West Palm Beach.

Then the renewal for his home insurance arrived. The new rate for the year starting in September was around $121,000—more than seven times what the Molinaris said they paid last year, and more than 13 times what they paid when the family moved to Florida in 2019.

While they found a better rate from another insurer, at about $33,000 it is still nearly double what they paid last year. The family this month listed the home for sale with an asking price of nearly $3.5 million after determining that insurance costs made staying there too expensive. Others in Flamingo Park told The Wall Street Journal they are drawing the same conclusion.

Paying nearly 1% of the house’s value for insurance is pretty expensive. But… “historic” in Florida? Here’s a house that I found on Zillow in that neighborhood:

It’s almost 100 years old. Is it made from concrete blocks and steel rebar like the typical reasonably new house in Florida? No. It’s a wood structure (“frame”):

So the New York-based journalists write about a 100-year-old neighborhood with the implication that this is typical for Florida. In fact, any house built after Hurricane Andrew (1992; made landfall south of Miami as a Category 5 storm) is likely well-defended against hurricanes. State Farm won’t write new policies on houses built before 2003, presumably due to the fact that a post-Andrew building code took effect statewide in 2002 (a similar code took effect just two years after Andrew in South Florida).

More from the newspaper:

“When you have a home that’s one million dollars or less, your insurance premium becomes higher than your mortgage,” he said.

Can this be true? The article mentions a bunch of folks paying about 1 percent of their house+lot value to insure an ancient wooden structure. Absent a huge down payment or a savvy purchase just after the Collapse of 2008, wouldn’t a 30-year mortgage obtained in pre-Biden times have to be at least 2 percent of the house+lot value?

Separately, there doesn’t seem to be a huge effect yet from the new laws. “Here’s why Florida insurance premiums aren’t expected to go down anytime soon” (WTSP, October 12, 2023):

Karen Clark & Co’s analysis says that while there are factors beyond legislative control causing homeowner premiums to rise, recent laws targeting lawsuits against insurers might at least keep future premium hikes smaller than they might otherwise have been.

According to data, Florida had 10 times the percentage of litigated homeowner claims compared to other states where major hurricanes made landfall. On average, claims that are subject to lawsuits cost about seven times more on average than ones that aren’t. With new laws reducing the amount of insurance claims taken to court, one of the factors driving up future premium costs might be mitigated.

I’m wondering about the highlighted sentence. Is that adjusted for the severity of the damage to the house? It makes sense that a $10,000 problem doesn’t result in a lawsuit while a $100,000 problem might.

Circling back to the WSJ article… the only way to save money is to move back to the Northeast where the WSJ is based?

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Can Israel find all of Hamas’s tunnels with ground-penetrating radar? And then what?

Prior to this latest over-the-fence attack, Hamas’s (“officially the Islamic Resistance Movement”) main military strategy was tunneling under the fence with Israel and emerging to fight on the unprotected side or tunneling under the border with Egypt and bringing weapons in. (see “Palestinian tunnel warfare in the Gaza Strip” from Wikipedia).

I’m wondering what stops the Israelis from finding all of the tunnels via ground-penetrating radar. Before we decided to open our border, we attempted to find tunnels connecting the U.S. and Mexico (DHS 2009). This 2014 article from The Times of Israel discusses the technology’s limitations:

Ground-penetrating radar, known as GPR, is among the most promising technological responses to the tunnels, Israeli and American experts say. The radar – which can “see” into the ground – has been used from the surface to search for smuggling tunnels under the US-Mexico border. Radar installations are also installed in deep holes in the ground to search for attack tunnels under the Korean Demilitarized Zone.

The experts say the Korean type of of cross-borehole ground-penetrating radar could be installed along the border to create a permanent detection barrier – deep enough to spot any tunnel Palestinians militants could dig. The barrier could be monitored for changes from a remote center, and in combination with other technologies could provide the best method of securing the border.

A limitation of ground-penetrating radar is that even in ideal conditions, it only provides an accurate image from the surface up to a depth of about 15 meters. The known tunnels in Mexico are as much as 27 meters below ground.

In the DMZ between North and South Korea, four tunnels have been found from the north running as deep as 160 meters below ground. The South Korean army – previously with guidance from the US Army Corps of Engineers – has on an ad hoc basis used cross-borehole ground-penetrating radar to look for tunnels as deep as 600 meters, …

In cross-borehole ground-penetrating radar, pairs of narrow holes are drilled deep into the ground and antennae are lowered into them — one for sending and the other for receiving the signals. From the boreholes, the radar can provide an image all the way down to the water table. However, there have been no reports of tunnels being found this way in the DMZ.

Maybe the water table is an issue? The Coastal Aquifer from which Gaza gets most of its water (pumping it out via wells) is only 20-50 meters below the surface and perhaps some of Hamas’s tunnels are deeper?

If Israel (or “the Zionist entity” as Hamas officials refer to the enemy) is on the surface inside Gaza, can they drill underground to place radar gear and come up with a complete subsurface map?

It looks like some USGS folks tried to do this in the mid-1990s to find old mine tunnels:

If the answer to the above is “yes”, then what? Suppose that someone with control of the surface wanted to destroy the tunnels. How can they do it? (I’m assuming that there won’t be any people inside the tunnels at this point. Presumably the Hamas fighters will migrate south and mix seamlessly into the civilian population, live off U.S. and E.U. taxpayers, then come back in 2024 or 2025 with a renewed vengeance.)

There are “bunker buster” bombs designed to destroy stuff underground, but wouldn’t it be simpler and cheaper to drill a shaft down into a previously-mapped tunnel and drop a modest-sized explosive into the shaft? If so, will Gaza be transformed for a few months into what looks like an oil-drilling field?

Related (very loosely):

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Aftermarket software for dishwashers?

Some people complain that dishwasher performance has been hobbled by regulations limiting water usage (see a comment on Science says to throw out all of your appliances, for example).

For showerheads, manufacturers deal with the regulations by making normal-flow devices in metal and inserting a plastic flow restrictor that any consumer with a screwdriver can knock out, thus bypassing the regulation and luxuriating in a powerful shower.

With automobiles, people who want to get the last bit of performance install aftermarket software for engine control (example from the UK; example from Norway). I’m wondering why nobody seems to have done with this dishwashers. Everything about the dishwasher is under software control, right? When to fill with fresh water, when to stop filling, when to turn on the circulation pump, when to turn on the drain pump, when to open the detergent compartment, etc.

What would stop a consumer from installing his/her/zir/their own control board that would do the following:

  1. fill the dishwasher with 2X the standard amount of water
  2. run the circulation pump for a while (assume the owner has put some detergent in directly on the inside of the door
  3. pump out the dirty water
  4. fill the dishwasher again with fresh water
  5. pump out the rinse water
  6. fill the dishwasher with 2X the standard amount of water
  7. open the detergent compartment
  8. run the circulation pump for a while
  9. rinse again

If the 1980s experience is what is sought, start with a dishwasher that includes a grinding disposer instead of a weak European-style filter (example: GE’s Piranha Hard Food Disposer).

What’s the flaw in the above theory? Are today’s circulation pumps nowhere near as powerful as what the dishwashers of the 1980s had? (I remember putting in pans with stuck-on cheese and they came out of a Whirlpool dishwasher completely clean; the machine was rather noisy, though.) If the pumps are as good as in the old days, it would seem that fresh software could restore function to pre-regulation levels.

Related:

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Single-stage versus variable-speed air conditioning dehumidification performance

After an exciting summer packed with three blower motor failures in three 6-year-old Trane single-speed air conditioning systems, the transformation of our house into a showcase for variable-speed communicating Trane/American Standard equipment is complete.

For background, see the folllowing:

The most humid part of our house was the upstairs. This contains two big bedrooms served by a 3-ton A/C for a calculated Manual J demand of 2.1 tons. Relative humidity was 58-62 percent with a TEM6 variable-speed air handler and a single-stage condenser.

Step 1 was replacing the condenser with a variable-speed “communicating” condenser that sends digital information back to the air handler over a two-conductor cable. Trane says that this new condenser is a match for the 6-year-old TEM6 so long as an adapter relay panel is installed. What they don’t say is that the result is a brain-dead system in which the air handler always runs at the same blower speed regardless of what the compressor speed is. Compared to the 6-year-old single-stage A/C, there was no reduction in humidity from this arrangement.

Step 2 was replacing the (working perfect with a new blower) TEM6 air handler with a top-of-the-line TAM9 air handler. Humidity immediately plummeted to a reasonable 51 percent on a wet hot Florida day with hours of rain, an 87-degree high, and humidity as high as 95 percent.

What does #Science say about this result? “Dehumidification performance of a variable speed heat pump and a single speed heat pump with and without dehumidification capabilities in a warm and humid climate” (Kone and Fumo 2020; Energy Reports):

the variable speed mode was able to maintain relative humidity between 50% to 52% on summer days. In the single-speed with enhanced dehumidification, a slightly less effective humidity control was achieved on summer days with the mode keeping the relative humidity between 53% to 55%. In the normal cooling mode, which resembles a conventional system, the humidity levels were controlled between 55% to 60%. In the shoulder season, the variable speed and enhanced dehumidification modes maintained the relative humidity between 55% to 58% and 53% to 56% respectively. In the shoulder season, the normal cooling mode kept the indoor relative humidity near or above 60%.

In going from single-stage to variable-speed, #Science found a reduction in humidity from an average of 57.5% to 51% (middle of the ranges given), or 6.5%. My data, consistent from a Govee sensor set and a $300 Airthings monitor, was 8-10% reduction in the relative humidity reading. The ground floor of the house still feels and measures less humid (40-50% depending on the location), but walking upstairs no longer feels like entering a steam room.

It’s tough to find objective data from anywhere else. Carrier is the only company, I think, that offers any numbers:

The Trane stuff has an emergency dehumidification capability in which it will run the heat strips as the same time as the A/C. Carrier also might have something like this (their commercial systems have a “reheat” mode that might do something similar, but using only the coil and not the resistive heat strips).

It is unclear from the Carrier page if they’re talking about using an extreme measure to dehumidify or just running the variable-speed in an optimized manner.

I’m also unclear what they mean by “400 percent more moisture” removed. If a single-stage system is removing 1 gallon of water, the variable-speed system removes 5 gallons when outside temp and thermostat temp are held constant? That doesn’t seem plausible. If it is hot and humid outside, the system has to remove a huge amount of water just to do its basic job (since cooling outside air will almost immediately result in 100% relative humidity and condensation).

If relative humidity is linear in the amount of water vapor, a properly sized single-stage system has already removed more than half the water that was originally present in the air (since cooling resulted in 100% relative humidity and the house ended up at 50% humidity). As great as Carrier may be (they’re headquartered only about two miles from our house here in Palm Beach County!), I don’t see how they can remove 5X the amount of water compared to a system that removes half of the water available.

(Why didn’t we get Carrier? We already had Trane gear and thought that we might be able to preserve at least some of it (we weren’t). Also, the Carrier dealer who came out to quote the project refused to deal with our house because of a splice where the wires exit the house near the condenser, claiming that their communication wouldn’t function properly.)

I can’t figure out why single-stage A/C continues to be the standard here in the U.S. Everyone in Asia has variable-speed equipment (all of the mini splits are variable-speed). Assuming a constant thermostat setting, a single-stage system is the correct size for only one outdoor temperature. Why wouldn’t people be willing to pay a little more for a system that can run at the correct speed for whatever temp Climate Change happens to dish out at any given hour on any given day? Is it that it is impossible to explain to consumers what a dumb idea single-stage A/C is? (Maybe it makes sense in Arizona, though, where there isn’t any humidity to begin with?)

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