The Evolution of My Hot Water System - Part 2

 In part 1 <Link> of this compendium, I described my experiments with creating hot water under power company demand billing and what some of the pitfalls were. In this part I want to discuss my technique of getting ENOUGH hot water on cloudy days. Sure, with the rainfall in the desert, this shouldn't be a problem; after all, the cold water is always over 80F during the summer. I guess I'm spoiled; I like a hot shower, not a lukewarm one. It's really pleasant to soak in a hot tub full of water with a book. Creature comforts are important.

We don't get many cloudy days, but there are enough to get annoying in the cooler weather when clouds take over the sky and solar just doesn't produce enough heat to give me enough hot water. What to do about that annoyance. After all, automating a house should make it more comfortable ... right??

Way back when I first started measuring the temperature of my water heater and recording it, I posted graphs and charts describing my findings. A couple of comments pointed out how my water heater was stratified, and I spent some time thinking about that and experimenting. Yes, the very fact that warm water rises and cold water sinks was causing much of my problem of not quite enough hot water. 

Let's take a look at what goes on inside a water heater, this is a typical electric hot water heater.

I grabbed this directly from a Sears site for illustration.

I'm sure they don't mind because it is free advertising for them.

Water comes in the top through a tube to the bottom, and when it is too cold, one or both of the heating elements turn on. This heats the water, physics works its wonders, and the hot water travels to the top. This, one would think, causes the water to mix and the temperature to equalize inside due to the motion, but it doesn't quite work that way. The top element actually reaches the set temperatue and shuts off, the bottom element eventually gets to its setting and shuts off also. That leaves around half a tank of hot water at the top and the cooler water at the bottom. 

Water is drawn from the top, so you get hot water at first, but as the water heater is drained, new cold water comes in through the input tube to the bottom, setting off the temperature sensor there and turning the bottom element on. That warm water rises and mixes some of the incoming cold with the hot water at the top. Your water heater is actually being cooled by new water and the circulation of the water inside the heater as it works. 

Then, on go the heating elements and up goes the electric bill. That shower after work and before the family notices how bad you stink from working outside all day combined with Peak Demand Billing just cost you an extra $40 on your electric bill. Those heating elements are usually 4500 watts each, and there are two of them for 9000 watts. If they run for an hour to heat up all that water, you just used 10kWh of power. If that happens during peak demand (like we have here), you WILL see that on your bill at the end of the month.

See why I put in a solar water hot-water heater? That left me somewhat less vulnerable to the chiseling, money-hungry bureaucrats at the power company. When I combined that with literally shutting off the heating element on the water heater during peak periods, I could pretty much thumb my nose at them because the bottom element is actually a radiator hooked to a solar panel on the roof that heats water and a pump circulates it in a closed loop that only transfers heat without stirring up the water inside the heater. Mine is sort of constructed like this:

This is called indirect solar water heating. The bottom heating element has been replaced with a radiator. A pump in the plumbing pushes antifreeze-treated water through the accumulator on my roof so the heating is held to a closed loop. The top element is still there and is called a helper element. It is a combination of both mains-powered electrical heating and indirect solar. My expense is only for the 45 watt circulation pump when the hot Arizona sun is doing its 'thing' and some minor 'top up' actions from the helper element at the top.

Now back to the stratification problem. The obvious (to me) solution is another pump in the plumbing. I have a nice hole in the top of the tank that I can use and another at the bottom as well; I should be able to pump water from one to the other and stir things up so the entire 80 gallons of water are at the same temperature. That will give me more hot water than I need and a long hot shower for the wife (happy wife happy life). All I needed to do was run a pipe from the bottom, through a pump, and into the top. That would solve all my problems. That's exactly what I decided to do.

First I gathered some parts and pieces to do the job: pipe, fittings, pump, and cleared out the garage where the heater was. I dragged in a water hose and hooked it to the drain line, shut off the water, and opened the drain faucet. The idea was to start draining it with pressure applied to force out any material that might have settled to the bottom 

Nothing happened. No water came out of the hose. I waited, still nothing. Felt the hose, and there was a little heat near the faucet, but it didn't go down the hose. What the heck? I went outside, to see if any air was being forced out of the hose, again nothing. I stood there scratchng my head and wondering what was going on. In a bit of desperation, I decided to pull the faucet off the bottom of the heater to see if it was plugged up. 

After turning off the water, I disconnected the hose, and it had some calcium chunks in it surrounded by a milky calcium-laden fluid. Yep, it was plugged. Now how do I drain a full tank of hot water with the faucet removed? And what about the possibility that the bottom of the tank was plugged with this milky stuff? I needed a way to let air into the tank so it would drain as rapidly as possible; how was I ... Oh wait, I also needed to replace the sacrificial anode at the top of the tank!! If I took that out it would let air in the top, and I could mess with the faucet to try and clear it. That's the ticket; pull the anode.

For those of you that have never pulled the sacrificial anode out of a water heater, here's some sage advice from someone that has done it themselves. Call a plumber. 

I didn't do that; instead, I tried a crescent wrench, then a bigger crescent wrench, then a piece of pipe on the handle of the wrench, then a longer piece of pipe. Nothing would budge that stupid thing. What exactly was the manufacturer's goal in putting that fitting in so tight? Did they locktite it in place to show us common folk how inadequate homeowners are at maintenance? Was it a plot to guarantee a plumber's trip to the house? Do plumbing manufacturers conspire with plumbing unions to guarantee work? Could it have been cousin Bubba, your 300-pound relative with a breaking bar, chuckling about how frustrating it would be for someone 10 years later trying to get it out? I suspect it was the setting on an automatic wrench on an assembly line in some factory somewhere. Some lazy inspector or quality control 'specialist' is not doing their job, and we get to pay for it in time, money, and frustration.

I didn't have a socket that would fit it; those things take a 1 1/16 socket. Who has one of those in their toolbox? Amazon to the rescue: I ordered a kit containing both the anode and the correct socket, then played the waiting game. My project ground to a halt, the garage stayed a disaster zone, and I was left entirely at the mercy of the delivery driver. For many hours, my immediate future, and the progress of my project were completely out of my hands. "Please mighty King Amazon, have mercy on your subject."

My whining must have worked because they arrived the next day, and I took the socket and my brand-new 1100 ft/lb impact wrench, and with a little wrangling around, I got the darn thing to unscrew. Think about this for a moment; I had to use an impact wrench that I have used to take the lug nuts off a 20,000 pound backhoe for a neighbor. I've intentionally broken the heads off rusted 3/4 inch bolts so I could drill out the hole it was in with that thing. I have to be careful to make sure the wrench doesn't turn me instead of the bolt. That kind of power should be reserved for an adventure with the bucket of an excavator, not a silly plumbing fitting on a residential water heater. Note to manufacturers: never underestimate the homeowner; we will overcome.

When I pulled it out:

Yes, maybe I should have changed it sooner...

The white stuff on it is calcim, not magnesium like it was supposed to be. Let this be a lesson to you readers: check that anode. However, in my defense, I couldn't get the darn thing out in the past. Yes, I tried several times, and this was the one time I actually succeeded. The power of the big impact wrench finally overcame the resolve of the rod being evicted from its home. Now I had air going into the water heater to let the water out. 

I placed a bucket under the drain faucet at the bottom of the heater and turned the water on. Nothing. This time there wasn't even a drip. Standing back and looking at it, I was a bit overwhelmed. So I tried a coat hanger as something to punch the calcium around until I could get some water flowing to rinse this thing. The coat hanger wire hit a hard stop in the faucet and wouldn't budge at all. Fine, I have pipe wrenches; it was time for the last resort ... pull the darn faucet out. 

I grabbed a good-sized pipe wrench, moved the bucket out of the way, and throwing caution to the wind, unscrewed the stupid faucet. Since there was no pressure other than the weight of the water, I actually got a slow flow of milky white goo. A little prodding with the coat hanger loosened it, and it actually started to drain on the floor of the garage. I just stood there and celebrated my limited success. Sure, I had a mess, but it was actually draining after hours of messing around with it. 

Turning my attention to the faucet, it was obvious why the darn thing defied me:

This is a view of the whole thing. Notice how they put on one that isn't like our normal hose bib out in the yard. This thing is long and looks like it is special in some fashion. Next is a view straight down the hose end of the faucet. Notice the typical valve that anyone who has worked with outdoor faucets is very familiar with. 

Let's look down the other end.

See that teeny, tiny hole down there? That's all that's provided to drain the darn water heater, that tiny little hole. That's what the chunks of calcium hit and wouldn't let water pass. That poor excuse for a drain is obviously designed to impede maintenance of the water heater instead of allowing it. Solar water heaters are expensive devices that should make life easier and cheaper. We pay big bucks to save money, and they put a faucet on for cleaning out the tank that limits flow to roughly what Grandma can suck through a martini straw. I decided right then that faucet was not going back into my water heater. 

Instead, I fashioned a new drain valve out of a short length of pipe, a brass fitting, and a nice ball valve that wouldn't restrict the water. Something like this:

These things allow full flow through the pipe and don't have a tiny little hole to plug things up. After I got that put together, I just plugged in the new sacrificial anode into the top using a lot of teflon tape coated with pipe dope and tightened it down with a regular short crescent wrench. I was not going to tighten that new rod in like the old one was; I wanted to be able to change it with an 8" crescent next time. I used one of those 'flexible' anode rods because I didn't want to inadvertantly screw up the radiator at the bottom of the tank. If I shoved one of the flexible rods into the tank, it wouldn't gouge a dent into the radiator. 

Then by attaching a water hose leading out to the yard, I was able to finally flush the heater of all the crap that had accumulated over the years. I filled the water heater, left the water pressure on and opened the valve. 

I watched the water come out the end of the hose, and the chalky residue flushed out pretty quickly while I watched for that demon of water heater destruction ... RUST. Fortunately, there wasn't any rust flushed out. Apparently, with the exception of the useless and damaging drain faucet, I had a good water heater. It hadn't rusted in spite of my lack of maintenance. 

I had just spent two entire days and hadn't made any progress at all toward my actual goal of putting in a recirculating pump to counter the stratification of the water heater. Two trips to Home Depot and a lot of stomping around the garage in frustration, and I was still just starting the actual process. Speaking of which, what's up with Home Depot? Have any of us ever found all the pieces we need? There is the advantage of getting more fittings than we need because they are great about returns, but having to go to ACE Hardware for a fitting when Home Depot is out is a pain. I do like the folks at both stores though, especially the ones at the return desk. 

BUT, it was time to get the hot water back on and clean up some of the mess I had with calcium all over the wet garage floor. The wife-comfort aspect of home automation is important. She should look forward to the new improvements in lifestyle, not cringe at her water heater being down for days while we stumble around making stupid mistakes and overcoming bad design decisions from some manufacturer or assembly line worker. Especially the part about waiting for an Amazon order to arrive.

So, I double-checked for leaks, dragged the hose out in the yard, and turned the heater back on for the night; the next step could wait until tomorrow. 

See you in part 3.

 

The 24-Volt Insurgency: Why Desert Packrats Are Mocking Your Peppermint Oil

There is a specific, primal horror to waking up in the middle of an Arizona summer night in a pool of your own sweat, checking the thermostat, and seeing a crisp 89 degrees staring back at you.

It’s even worse when you grab a flashlight, walk out into the hot, dark, pre-dawn desert air to inspect your air conditioner, and find that a furry, four-legged demolition specialist has systematically snipped your 24-volt control line, converting your life-saving air conditioner into a heater.

If this happens once, it’s an annoyance. If it happens three nights in a row, it’s a battlefield between the primal forces of nature and civilization as we know it.

What was going on?

For the last week, my northern AC unit became the epicenter of a tactical showdown between human engineering and rodent persistence. A huge inconvenience to me, but after a few midnight flashlight repairs and some serious crime-scene analysis, I’ve cracked the code on why they do it, why the internet’s favorite DIY remedies are absolute garbage, and most importantly, how to build a defense grid that actually works.

Add to that the safety factor. The default factor in home AC heat pumps is to heat. It seems better to be awakened to the heater running unexpectedly instead of the cooling. The engineers seem to think that uncomfortable heat is better than freezing to death in the winter from a rat breaking the 24-volt circuit. Living in Arizona, I might argue that, but my relatives in the Northeast would object.

The Soy-Plastic Myth vs. The "Perfect Toothpick" Reality

If you spend ten minutes on automotive or HVAC forums, you will run into the classic urban legend: "The government forced manufacturers to change the insulation to soy-based plastics, and now the wires taste like food!"

Let's set the record straight. While it’s true that modern car manufacturers did switch to soy-based bioplastics over the last decade (creating a multi-thousand-dollar buffet under modern truck hoods), it wasn't due to US regulations. It was companies pandering to environmental concerns.

This new insulation will, over time and exposure, decay—unlike petrochemicals that last forever. It’s lighter, easier to form, weighs less, and fills that niche of environmental awareness that sells so well to city dwellers who seldom actually see, much less live in, the environment they talk so much about preserving. The unintended consequence of this corporate virtue signaling? Your expensive vehicle or outdoor equipment has been converted into a gourmet snack.

However, before you go blaming a corporate marketing department for your broken AC unit, there’s a twist: your standard residential air conditioner thermostat wire isn't soy. It's still old-school, petroleum-based Polyvinyl Chloride (PVC). It smells like chemical garbage, not dinner.

So why did the rats keep coming back to my north unit to slice the exact same wire?

During day three of my investigation, I noticed something critical: The rats completely ignored the thick outer cable sheath. They only attacked the thin, individual 18-gauge colored wires after the sheath had been peeled back for the connections. "But why?" one asks.

It turns out it's a matter of biological imperatives. A rodent’s incisors grow continuously—up to five inches a year. If they don't constantly gnaw on things to file them down, their teeth will literally grow through their own jaws. This provides some clues to why, but also some cautions.

The thick outer jacket of an AC cable is too wide and smooth; they can't get a jaw around it. But an individual 18-gauge strand? That is the exact diameter of a small root or a piece of desert scrub. It fits perfectly into the sweet spot of their jaw mechanics. It's not dinner—it's a precision-engineered toothpick. Something to gnaw on to help grind down their teeth, and a low enough voltage not to roast them into a carbon footprint. 

Why Internet Remedies Fail: The Evaporation Trap 

Before we talk about what works, let’s talk about the absolute sales BS cluttering up the internet. In my time fighting the desert wire-eaters, I have systematically tested the "feel-good" remedies. Here is the field report:

• Peppermint Oil: I once sprayed a literal quart of high-concentration peppermint oil around the engine compartment of my truck. The result? I had the best-smelling, mintiest rodent hotel in Arizona. Once the initial vapor shock wears off in a few hours, the rat’s drive to chew completely overrides any objection the rat has to the smell. Trusting that home remedy cost me $2400 at the dealer having wiring harnesses replaced.

• Bitter Sprays: Products designed to stop dogs from chewing work for about 48 hours. In our brutal desert environment, the intense sun, heat, and ambient dust cause the bitter compounds to volatilize and vanish. Also, remember, the rat has to chew enough of it to taste the bitters. Our own experience with canine bitters has mixed results; some dogs react to it, and others ignore it and still chew off our baseboards and chair legs. How well would we expect it to work on a rodent that eats cactus (thorns and all), chews the bark off our fruit trees, gathers dried dog poop and uses it as a front door to its home, and leaves trails of its scat under our BBQ?

• Predator Urine: Buying fox or coyote urine sounds tactical, but rodents are highly adaptable. A desert packrat has no evolutionary memory of a European Red Fox. Even if you use local coyote scent, if the smell just sits there day after day without a physical coyote ever showing up, the rats figure out within 48 hours that it’s a ghost threat. Renewing the dosage only helps the rat to learn that the smell is not left by a predator simply because the threat never materializes. 

The Real Culprit: The Oasis Effect

While inspecting the unit on day four, I finally found the smoking gun. I noticed a distinct, wet patch of condensation pooling right on the base tray of the compressor housing. Look closely at the dust, and you can see the tiny, muddy footprints.

In the middle of a scorching summer, a guaranteed, daily source of fresh, dripping water is worth more than gold. The copper pipe carrying cold refrigerant into the air handler inside the house condensed the limited humidity of our desert air and dripped into that little reservoir at the bottom of the compressor casing. My AC unit wasn't just a hardware store; it was a five-star desert oasis. The rats were stopping by for a cool drink of AC sweat to beat the heat and then deciding to utilize the local 24-volt toothpicks while relaxing by the pool.

Before your environmental instincts kick in and you comment on how bad for the environment rat poison is, I had been three nights without sleep in a sweltering puddle of sweat, listening to complaints about the AC continuing to fail. What exactly would you have done? Cut me some slack here. Plus, this is some of the incredibly expensive rodenticide that only kills once. 

Even worse? Those green poison pellets I threw down were sitting completely untouched right in the puddle. The rats literally marinated their poison while ignoring it to chew on my wiring.

The Counter-Insurgency Playbook

To win a war, you have to change the environment. Here is the two-phase strategy I used to take back the north wall.

Phase 1: The Tactical Retreat to the High Ground (The Free Fix)

The rats were successful because the 24V lines were sitting on a low-level "lounge deck" right at chest height for a sitting rodent.

The service access to the AC compressor

Close up of the wiring area after two

repair attempts. 

I pulled the thin AC control lines completely out of that bottom open shelf. Then I rerouted the multi-conductor line from the house upward and fed it directly into the side knockout of the upper, enclosed high-voltage metal service area.

The 24VAC wires are on the bottom

And the 240VAC wires are on top.

By making all the wire-nut connections inside a sealed metal box, the target wires were protected. The only thing left downstairs near the concrete pad is a smooth, unbroken stretch of factory cable jacket. They showed up the next night, drank their water, and realized the wire playground was locked and went off to some other rat playground. We are currently four nights in with zero outages.

Phase 2: The Permanent Armor (The Parts List)

Once the immediate crisis is averted, it's time to build a maintenance-free fortress. Because we are dealing with a whole desert ecosystem—from tiny mice to heavy-jawed gophers, ground squirrels, and don't forget, rabbits—your best bet is to armor-plate the entire run from the wall to the chassis.

1. Mechanical Armor (Techflex F6 Heavy Wall Braided Sleeving: Instead of tearing your fresh wiring apart to slide a tube over it, use a split braided sleeve. The heavy-wall version has a built-in lateral overlap that snaps shut around the existing wire. A rat's teeth slide right through the slick woven matrix rather than grabbing and cutting it. Plus, the wire sticks them in their mouth, making it unpleasant enough to leave alone. 
   
   

   
   I've used this on my pool for months. 

2. Chemical Deterrence (Genuine Honda Rodent Tape) This stuff is the gold standard for a reason. Honda bakes micro-capsules of pure capsaicin (chili pepper extract) directly into the vinyl substrate. It doesn't wash away or evaporate in the sun like a spray. When a rodent punctures it, the capsules burst directly into their mucous membranes. It's true that the rodent has to actually chew on the tape to get the burst of capsaicin, but that's what rats do, chew.
   
   

   Safety Note: Always wear heavy gloves when handling the spicy tape, and for the love of God, do not rub your eyes, scratch your privates, or pick your nose afterward. You might also warn a repairman, but that's your choice.

End Result

Here's a picture of the AC unit after I finished it up. It has (so far) held up against the wandering rodents seeking cover and water. 

All the points where wires might get exposed are wrapped with rodent tape and  all the wiring is inside the wire sheath. Yes, those are stainless steel zipties; plastic doesn't last long here. I suspect this will hold up for a long time, but I'll keep an eye on it just in case of sun deterioration. 

Final Lessons from the Desert

If you live out in the rural desert, nature is always trying to reclaim your assets. If you park a vehicle outside, leave the hood up. Rats hate open spaces where hawks can see them, and they hate the sun. I've had reasonable luck with flashing lights; get some flashing Christmas tree lights and toss them under your vehicle to chase rodents away. This method does run the risk of the extension cord from the vehicle to the outlet getting chewed up though. For vehicles I use a combination of open hood and flashing lights that has worked well.

If your AC goes down, look for the water source, move your connections into protected areas, and armor the gaps. Let the neighbors deal with the mint sprays and the ghost coyote urine—stick to solid mechanical engineering and really spicy unexpected treats.