Tuesday, September 13, 2011

the taste of ice

Cold and frozen are not necessarily bad adjectives. In other words, they should not always conjure up negative or unwelcome memories. It's just a matter of perspective.

For example, in the Sonoran desert, the simple pleasure of having ice cubes always available to go in your freezer cannot be discounted in the relentless heat of summer.

It's more than simply a cold drink, after all one can simply pull a cold one from the fridge; there is tactile pleasure in the taste of ice. Provided, of course, that the ice tastes good.

A more extreme example: the Four Seasons hotel spa in Doha, Qatar, has a room that's basically a walk-in freezer. I've never seen or experienced anything like it.

You can walk in nearly naked and it feels wonderful for about 5 (to 10) minutes. And then it's not fun anymore.

I know I'm digressing but the point is: even being frozen is welcome sometimes, at least for a little while.

My house has a GE Profile refrigerator from the last owner. It's hardly the Doha Four Seasons, but still, despite GE's boast that the Profile line "offer the best in contemporary design matched with the latest kitchen technologies," it contained no icemaker. And in the desert heat? Go figure.

So it's perhaps a bit strange it's taken me so long to finish this tiny home improvement project. Still, I got it done. Maybe I have more spare time now. (Or I'm desperately trying to avoid some important work project.) On the bright side, perhaps I'm on a roll after that kick-ass wifi thermostat project (see here).

So I ordered and installed the optional GE ice maker specifically designed for my sleek but icemaker-less GE fridge.

A little inconvenient perhaps, you have to disassemble and remove the freezer door to get room to mount the unit. It goes into the top left side of the bottom freezer compartment.

You also need to run a 1/4" water line from the supply line in the wall behind the fridge to supply the electronic icemaker inside the freezer compartment. There is a special hole in the back of the freezer that it pokes through.

Thus equipped, the icemaker painstakingly mints orange segment shaped and sized slices of ice a few at a time. And it drops them into a tray inside the freezer.

Like a tuna boat that goes fishing, you'll want the freshest ice that's at the top layer of the tray. Especially the ones with the still wet sheen.

Older ice are significantly less fresh tasting: over time they absorb any odors from other items in the freezer compartment.

Moreover, the ice segments actually get smaller as well over time since ice dries out.

Unfortunately, this slow and expensive icemaker doesn't come with a water filter. I had to get this separately.

I can hear the clatter every so often when I'm in the kitchen when the icemaker decides to dump a batch of new, virgin ice segments. It's perhaps a little annoying but at the same time the falling ice informs me that I have fresh tuna, sorry, ice ready to go.
(Of course it also has a sensor that tells it when to stop minting ice.)

This is a GXRTDR GE SmartWater Inline Filter Cartridge.

To be clear, it's not a water purifier like the ones you'd use for camping in the wilderness: the water must be potable to begin with. It's not designed to render water sources like streams into drinkable water.

But it's supposed to remove 70% of chlorine, 99.5% of particulates (class V), sediment and rust. (Flouride is not affected.)

It's nothing fancy (read: inexpensive) but it's supposed to improve the taste of the ice as the packaging states (important!). It also lasts for six months.

Since there is no provision for mounting the filter inside or on the fridge. I drilled a hole for a snap-in bracket next to the supply line tap. Seems better than velcroing the filter to the backside of the fridge at any rate.

They stock this at Home Depot and the installation is clearly designed for hamfisted homeowners like me. In other words, it's trivial.

You snip the 1/4" plastic water line, plug one end into the top of the filter and the other end into the bottom.

It uses a simple but ingenious capture-mechanism that grabs the plastic hose, and automatically and securely makes it watertight (at reasonable pressures).

(You don't want to install an icemaker or filter and have the headache of water leaks.)

It has the unfortunate side-effect of making my slow icemaker work even slower. I guess that's to be expected. After all, my Brita water filter jug drips the water slowly too.

Still, well then, how does it feel to have good, fresh-tasting ice?

Well, to be honest, like some things in life, I kinda regret having waited so long. Summer is just about over. You see, it's already the week after Labor day now, and it's cooling down here.

Maybe, we'll have an Indian summer. Maybe I'll make a few fresh fruit smoothies just for the fun of it. And perhaps there's next year.

Sunday, September 4, 2011

Brave new world of wifi thermostats

A couple of years ago, I was looking around for a wireless thermostat for my house that I could access and set via the internet.

I was looking for the ability to save energy and remotely set the temperature to cool down the house while I am at the office just a couple of hours before I know I will be home.

Back then this stuff was not so easily available. Some required running an ethernet cable. Others required interfacing via some home control box. And they were expensive.

Now the technology has truly arrived at the mass market level. You can get wifi thermostats at Home Depot - which is where I picked up this one re-branded by 3M. Cost is $99.88 plus tax. Not a big premium over non-wifi enabled touch screen thermostats.

This one has a touch-sensitive screen plus the crucial ability to accept a separate wifi radio module.
(Actually it can accept up to two modules. Other than wifi, I guess there is at least a ZigBee home control module available separately.)

There's nothing wrong with my boring, old thermostat. It works reliably but there is no remote control capability.

You actually have to get up and go to the panel to set it or look at the temperature. On the new one, I'll be able to set things using my laptop or iPhone from anywhere in the house or the world for that matter.

In order to replace it, we have to figure out the existing wiring.

Let's pop the cover and take a look shall we? There are many possible wiring configurations depending on factors such as gas/electric heat, heat pump, single or dual stage or other options.

We need to figure out what wires are connected to the old one and what wires we need for the new thermostat.

A close up of the old thermostat with the wires coming in from the wall into the terminal block in the center reveals that I have a fairly standard heat/cool 4-wire single transformer HVAC setup.

In other words, RH/RC are jumpered together and there is a red wire into RC. A white wire into W, yellow into Y and green into G. Perfectly color-coded.

Unfortunately, my old thermostat is AA battery-powered only. The new thermostat requires 24V power via a C wire, which doesn't exist in my configuration.

According to the installation guide, you can separately buy and install a transformer to give you power but my friend Yuxiang Lin gave me an excellent piece of advice. He said that 24V is probably available at the furnace end of the wiring. And that I could connect this up using one of the spare wires. Wouldn't have to buy and install that pesky separate transformer mentioned in the installation guide.

Removing the old thermostat, I decide to prepare the (unused) orange wire shown here for the C wire.

My furnace sits in the garage. I decided it was a good time to change the HEPA filter too.

Removing the front panel, I see there is a large circuit board.
(Note, of course, needless to say we must switch off power to the A/C and furnace first before we remove the cover.)

Looking more closely, the white cable contains the other end of the wires that started at the thermostat inside the house.

Connected up in a row at the top left of the board are the white (W), green (G), red (R) and yellow (Y) wires.

Crucially, there is a terminal labeled C. Mercifully, a red wire connects there from another cable. So we have 24V power from somewhere!

We can also spot an orange wire peeking out. That is the same unused orange wire that I prepared at the other end. All we have to do is share this orange wire at the C terminal.

(I confess I screwed this part up initially. I connected yet another unused orange wire, which was the wrong one. Yuxiang Lin pointed out my mistake.)

So we've solved the missing but necessary C wire problem.

Back to the inside of the house, we can connect up the C (orange), W (white), Y (yellow), RH (red) and G (green) wires to the new thermostat as shown.

There are also two switches at the top left. Normal (NORM) or heat pump (HP). And gas (GAS) or electric (ELEC) heat. For my house, the settings are NORM and GAS.

The thermostat also requires 3 AA batteries (as backup perhaps?).
Anyway, we slot in the wifi module, reconnect the power to the furnace and A/C, and the thermostat boots up and works normally, even displaying a radio beacon.

However, it is not yet the all-singing and all-dancing remote wifi-accessible thermostat that it will be shortly.

To do that, we have to set it up on our home wireless network.

This involves two parts. Part one, we connect directly to the device via wifi (using a browser). Initially, it's its own ad-hoc network found at We just tell it the WPA2 password to join the home wireless network. Once done, it get a regular DHCP address on the home network just like a laptop would.
(To discover that assigned address, I had to connect to my router. This was before I had downloaded the iPhone app. The information is also available there.)
I guess one day this step could be done using the control panel itself. But currently, you need to aim your browser at the device first.

Part two involves registering for a Filtrete Remote Access Thermostat account. It's free.
(Initially I screwed up slightly here. I inadvertantly selected Eastern Standard Time and found the thermostat was 3 hours ahead of me. Easy to fix.)

It also asks for a PIN number which is displayed in lieu of the time when the thermostat boots up.

Using a browser on my laptop pointing to www.radiothermostat.com, once I'm logged in, I can view and set the thermostat by clicking on the picture of the thermostat. I can do this at home if I'm too lazy to get up and walk to the actual thermostat - like when I'm lying in bed.

Better yet, I can do this from work. Better still, I can check the thermostat and current temperature of the house when I am away traveling as long as I have an internet connection. No more uncomfortable nagging feeling as I board my flight wondering whether I've forgotten to switch off the A/C.

And best of all, I don't even need a laptop. I can see and control my thermostat from the iPhone.

So I also downloaded the free Wi-Fi enabled Radio Thermostat iPhone app (see here).

When I signed in, the app automatically downloaded the latest firmware for the thermostat and rebooted it remotely.
(I'm not sure if the web browser interface can do this. Have to check.)

Some other screens from the iPhone app:

As you can see, you can control everything from Modes (Off, Heat, Cool, Auto) to Fan (Off/Auto) to overriding temperatures for the current time period (Morning/Day/Evening/Night). (The exact duration of each time period can be defined via the browser or control panel directly.)

You can set a temperature and override for all time periods (Hold) until the hold is canceled. There is also a Home/Away button. (See first iPhone screenshot above.)

Moreover, I understand Radio Thermostat of America released an API that's well documented. I guess I should download that. However, since the iPhone app is so good, I haven't tinkered with writing code to control it without having to go through their server.

You can set up the 7 day + holiday programs via a web browser or from the control panel directly. However, this seems to be the only function not available from the iPhone app.

When I login using a browser and select Manage Devices, it shows my thermostat as model CT50 version 1.09. (See bottom picture below.) However, that's not the firmware version. The iPhone app shows that as 1.04.71. (See 2nd last picture from the bottom.) And there is an Update Firmware button that one can push if necessary.

In this brave new world of internet-enabled thermostats, I believe I can save energy without having to plan and stick to a preprogrammed 7 day timer (which I never program). This suits my lifestyle.

For example, I can pre-cool the house to an appropriate level if someone calls and wants to come to practice table tennis at my house. Or I can leave the thermostat at a higher temperature if I decide to hang out and work until closing time at that cool coffee shop near the campus. Awesome.

Friday, September 2, 2011

A sunset run

Today, we move to a new phase of my run training for this season. I did my first outdoor run today at 6pm. That's the time the university recreational running club meets on a daily basis.

So far I've only been running indoors on a treadmill: the simple reason being that even at 6pm it's still 37C (100F) outside at the moment.

6pm has its advantages though. The sun sets as the run proceeds. And this Friday's run is special: the club has decided to do one of my favorite runs on campus, namely the Parking Garages Run at the university. The idea is conceptually simple and beautiful in its implementation.

We run from multistorey parking garage to multistorey parking garage at sunset. These are dotted around the university. At each garage, we run up and down the stairs and across the rooftops. And if one is not in too heavy an oxygen debt to notice, one can catch a good view of the sunset and its colors at each location.

Here is a "bird's eye view" of the loop. Starting from the university Rec Center, we trace a clockwise route around the main campus visiting the 6th St garage, then Tyndall and the Main Gate garages, cut across campus and tunnel under Speedway to do Park Ave and Highland garages, then tunnel back under Speedway and finish with the 2nd and Cherry St garages. Oh, plus down and up the ILC (Integrated Learning Center) steps which - strictly speaking - is not a garage, and actually descends underground. Total distance is about 2.7 miles but that doesn't include running up and down the stairs at each garage twice. My iPod nano reports 400 kcal and and an optimistic total of 3.7 miles in just under 35 minutes.

Running in 100 degree heat is quite a challenge, not to mention the motivation of trying not to get totally left behind by the running club students. As a result, my max heart rate (HR) hit 170 bpm by the end. I must admit I felt quite out of shape. Still, it's a great run and as beautiful as one can get on this large and crowded campus.