Category Archives: Tips

Waterfree Urinals – how refreshing!

Today, I attended a music recital at one of Santa Clara University’s concert hall. During the intermission, as usual, I had to use the restroom. So I relieved myself on this Falcon Waterfree urinal but I couldn’t find the flushing valve when I was done. Upon reading the sign, I discovered this was a waterfree urinal. I’ve heard about this from Wall Street Journal last year or so but never used one. The natural thing for me to do was to take a deep breath and tried to sniff out any odd oder. None. How curious and nice!

When I came home, I did my research on how this water free urinal work and was utterly impressed with its simplicity. Click here for more details on this technology. I was suspicious of the proprietary cartridge cost, which is $35 for 7000 usages. Not bad at all. They even have monthly plan with or without installation.

This is a real winner from the business, and users’ and environmental perspective. Would be nice to install one at home. Probably hard to justify since I’m the only male in the household. 🙂

Movie “I am Legend” and DVD Play Kiosk

Yesterday, we rented the movie “I am Legend” from the DVD Play Kiosk box at my local PW Supermarket. This is the first time we use this srevice. I thought it’s a pretty good business model. The customer gets the convenience of renting and returning the DVD from/to the place they shopped – supermarket. The supermarket gets the customers to return to the store the next day for more shopping experience. Of course, if the customers don’t want to return the next day, there is a $1/day penalty. Very nice business model – win win for everyone.

Now back to the movie. “I am Legend” is about this guy who managed to survive the biggest catastrophe of the man kind – a viral outbreak that wiped out majority the people and turn a minority into “darkseekers” – vampire-like, super-aggressive human that only come out at night to hunt on the not-yet infested people or other animals. The movie evolved from the a calm, boring scenario like “Castaway” where the “only” survivor lives an extemely lonely, isolated kind of life, roaming around the empty New York streets littered with abandoned cars and weeds. As the story goes, the audiences start to discover the “dark” side of the silence in the day time. At that point, the movie turns into a horror movie. Will Smith becomes the Legend due to his discovery of the serum and the sacrifice of his own life to save the serum.

I think Will Smith’s acting is very good – believable – in this movie. The “nightseekers’ are clearly computer graphics and not as believable – too plastic. Overall, the movie has entertaining value and is not bad for people who enjoy scifi and horror movies. The empty New York street scenes are very rstrange – hard to imagine New York to be that quiet. Furthermore, the movie makes people think what is like to be the survivors of the earth where the majority of the people disappear suddenly. Perhaps, a run-away man-made virus is one the of the ways to make human extinct like the dinosaurs. Hopefully, we are still a long way from extinction.

Understanding “Sacrificial Anode”

In today’s Discovery Channel program “Some Assembly Required,” I saw how a metal coffin casket was made. Besides the usual heavy metal stamping and automated welding machines, the topic of “sacrificial anode” was explained. In my opinion, this is probably the most important “technology” used in the design of the coffin. The sacrificial anode, normally made of zinc, was attached to the bottom of the steel casket to sacrifice itself to the oxidation (losing electrons) process with the soil outside, instead of the steel being oxidized. A Wikipedia explanation is here. I was surprised to know that almost all the water heaters has an sacrificial anode rod to perform the same function. A longer-warranty heater may have a larger or even two of the anode rods made of magnesium or aluminum. Here’s a good explanation for it.

I like this program. It’s entertaining and I usually learn something.

Sprinkler system kept blowing the fuse

The winter raining season is almost over. It’s time to turn on the sprinkler system to keep the lawn green. When I did that over a week ago, I noticed that the sprinklers did not work. I went to check on the automatic sprinkler system and noticed that the power was off; the backup battery was keeping the system up with a display of “POWEROFF.” I traced the problem being the fuse was blown. No problem. I went to Fry’s and bought a box of 5 fuses (Glass type: 3AG 500mA) at 750mA (Fry’s ran out of the 500mA type). So I replaced the fuse. Done.

After a couple of days, I noticed the sprinkler still did not turn on. (I should have checked the sprinkler in manual mode – a lesson to be learned – validate your fix immediately.) I then spent sometime to manually stepping through each station and found that the fuse gets blown during station 1. So I removed the wire to station 1 and verified that the wire has been shorted. I suspected that the transformer for Station 1 may be broken/shorted.

During the weekend, I checked the entire wiring for all the wires and found that the wires were all cracked up under the sun. After some debugging, the short (1~2 ohm vs. 25 ohm normally) turns out to be at the mid point at the exit point of the house, not at/near the sprinkler station. I took the opportunity to replace all of the wire joints and added brand new insulating electrical tape to the wiring. The problem was then fixed.

Fixing the flood light

My flood light had not worked for a while now because the battery-operated remote motion sensor kept the lights turned on all the time, wasting lots of electricity. Today, I went to Home Depot and purchased a new one with the built-in motion sensor, hopefully getting rid of the need to replace batteries. But as it turned out, the diameter of the plate for the new flood light was 4″ instead of 5″ for the existing plate. I had to return it. Thanks to the liberal policy of Home Depot, they took it back without asking any question.

During the replacement process, I discovered there is a flip door that opens underneath the remote sensor. After switching on the “test” mode, I discovered that the remote sensor seemed to work OK. I re-seated the batteries and slided the mode to 1-min turn-off time. After testing for a few times, I was now convinced that the remote sensor was working just fine. The 1-min turn-off makes the “validation” so much easier and faster. Also, there is an LED that lights up when motion is sensed. This also helped the validation process. I guessed my original problem was that the batteries weren’t seated properly and I was testing it during day time, which caused the motion sensor to turn off completely due to the photocell within the sensor. (There is a switch inside the battery compartment to turn on the motion sensor during day time.)

My main learnings are as follows:
1) Don’t assume the system is broken under you understand how the system works first. Since I didn’t have the instruction manual, I had to check a comparable system at Home Depot to truly understand the definition of the remote sensor switches.

2) Before buying a new system, make sure the it will fit into the old system, or you may end up with a lot of retrofitting – it’s hard to cover a big hole with a small plate. In this case, it’s cheaper to replace the system with the same model.

Furthermore, during the same trip to Home Depot, I purchased a couple of timer-controlled sockets for the two front portion lights because we tend to turn on the lights at night and forget to turn them off even in the next day, resulting in lots of wasted electricity. There are several ways to resolve this problem. 1) Buy a timer-controlled light sockets that turn off the light after a certain number of hours or the built-in photo-cells can turn off the lights automatically when the day light is detected. 2) Use a timer switch to control the turn-on/off time automatically. 3) Use low-wattage fluorescent light bulbs and make it a habit to turn it off in the morning.

Well, here we go again. Obviously, I chose the #1 option (timer-controlled socket). The timer socket extends the light bulb too far down, thus exposing the light bulb – not pretty. #2 option costs $20 and some wiring work and I dread programming any timer. I decided to go with #3. It is simply not worthy of my thinking about it. Sometimes, the best solution is just changing your behavior. In the case, I can make it a habit for me to turn it off on my way back from picking up the newspapers. Done!

Replacing Filters for a Reverse Osmosis Water Filtration System

Today is the MLK Holiday – my day off. I decided to replace the filters in my 5-stage reverse osmosis (RO) system (Watt’s Premier Water WP5). According to my record, it’s been almost two years already since I replaced the filters. The filters consist of a sediment filter (1st stage), two carbon block filters (2nd and 3rd stage), the membrane (not replaced this time due to its high cost ~ $60) and the final finishing filter or GAC filter. As it turns out, the filters were not that badly soiled. Compared to my experience in my previous San Jose home, the Sunnyvale water is a lot cleaner.

GAC = Granular activated charcoal is made from raw materials (such as coconut shells or coal) that are high in carbon. Heat is used to increase (activate) the surface area of the carbon; this is why these filters are sometimes referred to as “charcoal” filters. The activated carbon removes certain chemicals that are dissolved in water passing through a filter containing GAC by trapping the chemical in the GAC. However, other chemicals, like sodium or nitrate, are not attracted to the carbon and are not removed.

I first shut off the valve to the RO system and proceeded drained the clean water, ~ 2 gallons, from the storage tank until the water is completely drained out. I then replaced the filters from the 1st stage to the last. This took me about 1/2 hour. The key things to watch out for: 1) Have a large towel already to handle the excessive water during the removal process – even after the valve is shut off. 2) Use the paper towel to clean the inlets of the cartridges and the inside surface of the cartridges. 3) Use Teflon tape to seal the threads on the tubes going into and out of the last GAC filter.

After I was done with it, I checked the Internet for several interesting facts for my own knowledge.
1. The principle of reverse osmosis was first apply to getting solvent out of solution. It’s very interesting that the membrane act as a barrier to separate out large molecules (impurities, minerals and etc.) from the clean water. The clean water will infiltrate into the dirty water to reach an equilibrium – an osmosis process. By applying the pressure on the raw water side, thus the name “reverse osmosis,” one can separate out the clean water. It’s like using the city’s water pressure topush the clean water through the membrane, which traps the impurities. The residual impure water gets flushed out of the RO system as brine water. More diagrams below. The salt water de-salination works the same way.

2. The zero-waste RO system redirects the brine (waste) water back to the hot water faucet for recovery. Not sure what purpose this would serve. My experience is that they tend to get drained out first because it isn’t hot enough in the first place.

3. The permeate pump is an interesting concept to reduce the water waste. By regulating/reducing the permeate output pressure, the RO membrane can work more efficiently, wasting less water or producing less brine water. A good explanation of how it works is here.

My conclusion is that I like to keep things simple. Having more parts and more interconnects will likely make the system less reliable, thus susceptible to water leaks and other maintenance issues. The water waste is not that bad for a 3-member household like mine. It’s much harder for me to justify adding the complexity just to save a few gallons of water. Yesterday, I visited Costco and saw a new version of RO system that has a quick-release for the filters, thus making the filter replacement work a lot easier. It’s definitely a step in the right direction. They would sell more filters (~$20 per set of 4 filters, except for the membrane) because the filters are much easier to replace.