I can’t hear that John Mayer song without thinking about our four daughters and not just because they’ll probably choose my nursing home.

The Lovely Marianne and I managed to have four daughters in three years. We had three of those kids in just 13 months. OK, so we cheated the last time around with twins, but still.

Erin, our youngest by five minutes (she’s a twin), took an interest in the heating business and went on to buy HeatingHelp.com and the rights to my books from TLM and me. She’s better at it than I ever was, and she sees things in the industry that I missed. I’m so proud of her.

I’m also proud of the others, but in different ways. They’re all very successful in their fields. They married good guys and we now have all these adorable grandkids knocking things over, but the heating bug bit only Erin. I’m blessed by that because we got to keep the family business in the family and I’m having a ball watching her do the things she’s doing. I also like the checks she sends us each month.

Meghan, who is 13 months older than her twin sisters, works for the United States Agency for International Development and travels the world trying her best to keep tuberculosis from showing up in the U.S. We’re supposed to be done with that horrible disease, but it’s always as close to us as the next arriving commercial jet from an African nation or the Philippines. Growing up, I had no idea Meg would choose this as her life’s work, but it serves to remind me that no matter the plans we have for our kids, they will become who they will become. I raised all four daughters with delicious tales of the heating industry, but only Erin’s eyes lit up.

After college, Meg joined World Teach for a couple years and went off to teach little kids in a tiny village in the mountains of Costa Rica. She lived with a very poor host family and learned Spanish quickly. One day, I asked her how they heated their water for the shower.

“I don’t know,” she said.

“Well, I’m curious, Meg. Could you find out?”

“OK.”

A day later, she sent me a photo of an electric showerhead that plugged into an outlet.

With an extension cord.

In the shower.

“Are they crazy?” I asked.

“What do you mean?” she asked. “They said that’s how everyone in the village heats the water. I mean those who can afford it.”

You know those electric heaters you drop into a cup of water to make instant coffee? Yep, that’s how this showerhead worked.

“Meg,” I said. “Do you think you could unplug that and just take cold showers?”

“Dad, you’re being silly.”

When she was a junior at The College of the Holy Cross in Worcester, Mass, she lived on Caro St., with lots of other students. She was very excited about this move because Caro St., is slightly off campus and the place where the parties were. She and her five friends had put in their names two years earlier to get the privilege of living in a three-story Irish Battleship, built, or so it seemed to me, without a level or a plumb line. When I was moving her furniture in that summer, I noticed the building had no heating system.

“You’re being silly, Dad. This is Worcester. It gets really cold here. There must be a heating system.”

“There isn’t, Meg. Trust me.”

“That’s crazy, Dad. There must be.”

You know what it was? The stove in the kitchen. That was the heating system for the whole floor. The landlord told them to keep the doors between the rooms open and use fans to blow the heat around.

“Even the bathroom door?” Meg asked.

“Sure,” he said. “You’re all girls.”

Meg and her roommates were OK with all this and the parties were good enough to draw the Worcester Police each weekend. I suppose this dump was good preparation for the Death Shower of Costa Rica.

The New York life

When she had enough Pura Vida in that tropical country, she returned home and moved into an apartment in Manhattan with one of her college roommates. They lived on the fifth floor of this old tenement that had steam heat from the 19th century. She called me one day to tell me there was a noise coming out of the “little silver thingy” that stuck out of the side of the pipe in their kitchen. At least she thought it was a pipe. “It’s hot.”

“Who is this?” I said.

“It’s me, Dad. Meghan? Your favorite daughter?”

“Little silver thingy?”

“Yes. The noisy silver thingy. On the hot thing. It’s noisy. Why?”

“Who is this?”

“Dad!”

So be good to your daughters, but don’t be surprised if they have no idea how a building stays warm.

But then, in fairness, I know nothing of TB.

To each her own.

Meg married John, a mechanical engineer, which was a blessing. John’s job has him traveling to foreign countries to project-manage HVAC systems as complicated as John Mayer’s social calendar.

Our John was off ministering to one of those systems, so The Lovely Marianne and I stayed with Meg and the two grandkids for 10 days when the wind was rattling Bethesda, Md., and even the thermometers were shivering. They live in a rented townhouse. It’s a lovely place for three of the seasons. Not so lovely during the winter.

The two-story townhouse has a heat pump.

The heat pump has one thermostat.

It’s downstairs.

Hot air rises.

So there we were, sitting on the couch on a day when even sunlight was freezing. Upstairs, where everyone slept, was sort of OK if you had enough blankets. Sort of.

Downstairs was like a meat locker. The curtains were moving because Bethesda contractors don’t know what caulking is. The wind was clawing its way under the door and through that ridiculous mail slot in the door’s center. John had stuffed insulation in the hole but the wind just laughed at that.

“Are you cold, Dad?”

“No, Meg. I’m fine,” I lied, not wanting to add to her already-high electric bill. She asked this because I was wearing all the clothes I owned.

“We’d love to buy one of these townhouses. It’s so convenient to the stores and the Metro,” Meg said.

“What are they asking for these?”

“About six-hundred thousand,” she said. “It’s out of our price range, but we can dream.”

That’s what they get for these drafty iceboxes. Because it’s convenient to the stores and the Metro. No insulation or caulking, but convenient to warm things that can get you away from it.

I sat there shivering and thinking about how oblivious most Americans are when it comes to HVAC, and how marble countertops and soaring ceilings will always win out over well-planned building envelopes and delicious hydronic-heating systems.

The reason the frigid countertops win is because most Americans are blind to the mechanical features of a home. That stuff hides in basements and closets. They don’t see it. They feel it when it’s not working, sure, but they don’t see it. And sight always beats touch. So does sound. Meg didn’t notice the little silver thingy on the hot thing until it started whistling at her.

We raised four wonderful daughters in the same house, treating them equally. One out of the four had an interest in the stuff that interests you and me. The other three, as brilliant as they are, rarely wonder about how it all works. Why is it warm (or supposed to be warm) indoors when it’s so cold outside? How does all that happen? Who cares?

It’s just the nature of people, and our daughters are your customers. We all have different talents and different interests, and as I said, I know nothing about tuberculosis. That’s Meg’s specialty.

I do have to admit, though, that when she called the Hoffman Specialty #40 steam air vent a “little silver thingy,” I did consider taking her out of the will.

But then that nursing-home decision lurks.