Honeywell Water Heater Thermostat Woe – How I Fixed It


I heard a scream from my wife in the shower, “No hot water! No hot water! What’s going on?!” Not good. This was 10pm two days ago. My first thought was that the water heater pilot light went out, based on my past experience. What else could it be? I checked that AO Smith Gas Water heater in the laundry room right away. The water heater comes with a sophisticated, advanced Honeywell Water Heater thermostat/valve that provides continuous monitoring of the water temperature and turning on and off the gas accordingly – all without battery. It uses a “thermopile” technology that converts thermal energy into electrical energy. It’s composed of serveral thermocouples connected in series to create roughly 350 mV of energy. What a nifty device!
honeywell-module

Except when it’s not working.

I first tried resetting the module by turning it to off and re-start the pilot light by turning the dial to “Pilot”, holding down “Pilot” and push the spark igniter. The system kept coming back with 4 flashes. Based on the “Status Light Code,” it means “Temperature Exceeded.” It made sense as we had a heat wave recently. So I figured the system should reset itself once the over temperature condition goes away. I kept resetting the system without much success to get the gas burner to turn on again.

I googled around and came across this website by Tyler Tork. Wow, so many people had the same problem dating back to 2013. The problem is that the microcontroller inside the unit remembers the last “over-temp condition” and would not forget it. The recommended fix is to disconnect everything from the module for an hour and let the power dissipated to “flush” out the memory.
honeywell-module-labels

That sounded easy. I tried disconnecting it for 30 minutes. No go. 60 minutes: No go. I left it disconnected for overnight. Still no go. I even flushed some of water out to get the sediments out as it’s a source of heat barrier that contributes to overheating.

One of the people commented “shorting” everything on the little printed circuit board to really “short circuit” the memory cell, most likely the big capacitors. And that’s what I did, I figured I have nothing to lose as I would need to replace it if it didn’t work. So I removed the PCB (printed circuit board) from its housing by unscrewing the torx screw and snapping the PCB from the housing. Then I took a sheet of aluminum foil (an electricity conducting material) and touch all the various solder joints (silver-looking blobs) especially the big capacitors, which are the energy storage devices. See figures.
pcb-component-side
Honeywell PCB Bottom Side
Then I put it back to its housing and put everything back to its original positions. Turn on the pilot and hit the spark lighter. I first saw the LED flashed 7 times, which means “Gas Controller Valve Failure.” Doesn’t sound good. Then I proceeded to dial it up to temperature setting A. Immediately, the burner turns on and we have a lift off! After a minute or so, the LED started blinking once and paused and blinking once again. This means “Normal Operation.” We’re back in business now. I just saved $110 (Walmart’s price) for the module and enduring days of suffering through cold showers and complaints from my family members. Viva DIY!

Book Review: “Bonk: The Curious Coupling of Science and Sex” by Mary Roach


After reading this book, I felt I had just taken another sex education class. I’m amazed by how the researchers in pursuit of science would do to acquire the data they need. They took criticism from people in general while contributing to demystify human sexuality. They are true pioneers.

I even learned a few things I never knew before like:
– how each part of sex organ works exactly.
– There were so many sex researches since as far back as science researches were recorded.
– Best indicator of organism is heart rate and blood pressure, better than its use for detecting lies.
– Animal sexual behavior is not too much different from ours. After all, we all have to derive pleasure from it in order for our species to survive the evolution.
– Dr. Hsu from my home country, Taiwan, is a world-famous penile surgeon in fixing erectile dysfunction and other male-organ-related illnesses.

This is an interesting and thought-provoking book for people who enjoy reading about difficult and controversial researches. Funny at times in Mary Roach’s side comments. Highly recommended.

Summary from each chapter:
1. Highlights from the pioneers of human sexual response. In this chapter, Author highlighted the pioneers in human sexual research. Started with Albert R. Shadle, who peered through animal sexual behavior in 1940’s. John Watson observed sexual behavior in the lab settings in 1910’s. Alfred Kinsey performed the experiments in secrecy. In 1960’s, William Masters and Virginia Johnson performed and published the controversial “Human Sexual Response” book. It was the “right” time as the society was more open to it. He had a penis camera built to better observe the “action.”

2. The orgasm machine for woman. The author describe her search for the penis camera without success and witnessing the orgasm machine in an exhibit event. The fact that the woman had a better control of the speed, angle and thrust may explain why they could get off using the contraption.

3. Some theories about why some women don’t experience normal “voluptuous reaction” – orgasm. The distance between vagina and clitoris may play a role – ideally less than the width of the thumb or the “rule of thumb” by Kim Wallen of Emory University. The distance seems to be proportional to the height of the woman and breast size – bad news for tall women with big breasts. G-spots are discussed quite liberally here – stimulating through different positions (doggy style). Or maybe it’s purely the sense of control that allows a woman to reach orgasm.

4.The author describes the artificial collections of boar sperms and insemination of sow. Some of the youtube videos may do a better job. But the question lingers whether female animal experience organism and whether organism helps with fertility. The answers are most likely ‘no’ for animals or at least no discernible by humans.

5. In this chapter, the author convince her husband to have a MRI 4-D (3D + time) imaging of their sex act and ejaculation. Now that’s professionalism.

6. This chapter started out with the work of Dr. Geng-long Hsu of Taipei, Taiwan who specialized on repairing penile injury and erectile dysfunction. The history of impotence is then described in great details. In the Middle Ages, it was blamed on witches. Then the psychological state of the men was accused, followed by many ridiculous causes like masturbation. Impotence could be a cause of divorces in the late 16th and early 17th century.

7. The author investigated boosting virility with transplanting animal and human testicle, ingesting animal testicles, and other means. Use of Viagra brings in more discussion. It ended with suggested pelvic exercises.

8. If you must, inflatable penile implant maybe the way to go. Roach described Dr. Hsu’s operation on a patient and even got to touch his penis. If the penis is castrated by a jealous wife accidentally, of course, the cure could be in the hand of their microsurgeons, though not to its full potential.

9. Is the clitoris a tiny penis? Yes, but Viagra doesn’t help in woman’s FSAD (Female Sexual Arousal Disorder).

10. Can frequent masturbation (or resulting in orgasm) contribute to your health (or hiccups in one case)? Roach investigated the use of vacuum pump for women’s clitoris that seem to increase flood flow. Roach paid a visit to Topco, US’s largest sex toy maker, which was an interesting encounter with their employees.

11. Orgasm can happen in quadriplegic persons or came about without physical manipulation (hand-free). The nerve paths from organism evidently are NOT blocked by spinal cord injuries.

12. Female sexual arousal poses a challenge for scientist to detect and unlock its mystery. In most cases, it’s in their mind. A promising drug, flibanserin, appears to be effective and in Phase III trials.

13. Sex studies in conservative countries like Egypt could be very difficult. But merely talking about sex already help the society to pay attention to it.

14. The last surprising experiment performed by Master and Johnson was this random matching of sexual partners. Almost all of them had “efficient” sex but not necessarily “amazing” sex. Gay men and women tend to pay more attention to their partners’ needs while heterosexual didn’t benefit from “gender empathy.”

See Mary Roach’s Ted Talk on 10 Things You Didn’t Know About Orgasm | Mary Roach