Tuesday, December 15, 2015

Almond+ Router/Smarthome Hub Plus CT100 Thermostat = Remote Control Heat

A few years have gone by since I wrote about the original Almond touchscreen wi-fi router and range extender and my consulting relationship with Ram Malasani, the founder of the company that makes it.

Since then Ram initiated a Kickstarter campaign to fund a successor product that he dubbed Almond+.  I joined 7,606 backers who pledged $855,625 to fund the campaign and ponied up $95 for an early production unit, which combines an advanced wi-fi feature set with built-in Z-Wave and ZigBee smarthome capabilities.  (Ram also asked me to produce a user guide for Almond+, but despite managing to knock out basic set-up instructions I found I was unsuited to the hectic pace of documentation writing.)

During my brief stint writing Almond+ documentation Ram supplied me with a couple of other Almond+ test units, both of which have performed flawlessly, plus a few low-end smarthome gizmos (e.g., power plugs and motion detectors) and, eventually, a 2Gig CT100 Z-Wave thermostat.

The CT100 got my attention.  My wife and I have a cottage in upstate New York, where winter temperatures routinely drop into the single digits.  Being able to monitor the cottage’s thermostat remotely and turn it up before arriving sounded pretty sweet.

Last month I finally had the chance to remove the old thermostat upstate and replace it with the CT100.  And because I’d already made a video illustrating how easy it is to set up the original Almond as a range extender, I thought it would be useful to make another illustrating how easy it is to install the CT100 and pair it with Almond+.  Have a look:

Truth in advertising prompts me to admit that as easy as I made this installation appear, there’s an important power issue about the CT100 that, for the sake of brevity, I left out of my video.

How Long Will the CT100 Work on Batteries?

As my installation makes plain, the Honeywell thermostat I removed, like an old-fashioned landline telephone, doesn’t need an external power source to function.  The CT100, on the other hand, needs at least four AA batteries.  Long before installing the CT100 I removed the cover from the Honeywell unit and, with a little online research, determined that neither of the two wires it uses supplies current.  Once I’d satisfied myself that the CT100 would work on battery power alone I began to wonder: just how long would it work?

In principle I wasn’t crazy about using a thermostat whose batteries had to be changed periodically, and frankly I was worried about the batteries running low in the dead of winter when the cold and snow make upstate visits a hassle.  Then there was the prospect of a power outage.  In the absence of power the original Honeywell thermostat is also useless, but I wasn’t sure if the CT100 and Almond+ would resume chatting to each other—and to me via the Internet—once the power came back on.

Especially since, long before installing the CT100,  I’d done a test pairing with Almond+ and noticed that after a few days Almond+ seemed to lose touch with the thermostat.  That, at least, was the conclusion I reached when I used the free iOS app that Securifi provides for monitoring and controlling connected smarthome devices.

While at the cottage upstate I’d try turning up the heat on the working Honeywell thermostat, wait for the temperature to rise a few degrees, and then, once the CT100’s internal thermometer also reflected the change, see if its new temperature readout successfully reached the app on my iPhone.

Unfortunately, it often didn’t.

Rebooting Almond+ solved the problem, but only temporarily.  In a matter of days it would once again lose touch with the CT100.

When I told Ram about the problem he suggested I try using a beta version of the Almond+ firmware—one that allows a user to set automated rules, including one to tell Almond+ to reboot at regular intervals.  (BTW: This beta version has since been released.)  Sure enough, after telling the firmware to reboot Almond+ every morning at 5 AM I found it reliably communicating with the CT100.

But then, I was still stuck with a thermostat that relies on battery power to function.

The Key to Running Thermostats on Household Current: The “C” Wire

As I was to learn, because the thermostat wiring in our cottage is missing the mysterious “C” or Common wire, which supplies current, I had no choice.  (The original Honeywell thermostat was so simple it didn’t need external power.)

And yet, when I took a closer look at the thermostat wiring coming out of the wall I discovered there weren’t two wires sheathed in the bundle, there were three.  One had been tied off because it wasn’t needed.

I took a look at the controller attached to the furnace and saw that, sure enough, the third wire in the bundle was tied off at the other end, too (see the red arrow):

Would it be possible to replace this controller with one that supplies current?

Grayfurnaceman to the Rescue!

What I needed was a furnace nerd.  A little searching on YouTube revealed a channel called Grayfurnaceman and a related website called Grayfurnaceman.com.  The website homepage graciously offers a contact form “for comments, questions and help with troubleshoot[ing].  Feel free to ask and I will try to help.”

So I asked, and Grayfurnaceman helped:
There is a control that includes a 24 volt transformer that can power the thermostat.  Here is the Honeywell part #:  R8184M1051/U.  It has pretty much the same high voltage wiring as your control.  Hope this helps.
It does.  Thanks, Grayfurnaceman!

Lately Honeywell part #: R8184M1051/U has been on my mind. Since I installed the CT100 my Almond iPhone app has been reporting a declining % battery charge in those fresh AA batteries I installed.  Here’s a screencap I did today:

That 83% charge is worrying.  It’s been only 5 weeks since I installed the CT100.  If its batteries lose 17% of their power every 5 weeks they clearly won’t last more than 6 months!

Aside #1: When I first installed the batteries in the CT100 it reported their charge as 97%, so I suppose it’s arguable they’ve lost only 14% of their power over the first 5 weeks.

Aside #2: For a while I had my iPhone’s Almond app set to notify me anytime the CT100 recorded a temperature change.  So every few hours I was getting push notifications about swings of a single degree as the thermostat kept turning the furnace on and off to keep the house at the steady 60 degrees Fahrenheit I’d selected.  Suspecting these notifications were adding to the drain on the batteries, I eventually turned them off.  So it’s possible that alarming 17% loss is attributable largely to my profligacy with push notifications.

Almond+ Now Supports Nest, Too

And this just in: yesterday’s edition of The Verge reports that Almond+ now supports the Rolls Royce of thermostats, the Nest, as well as such other Nest products as the Nest Protect smoke detector and Nest Cam security camera.

A little Googling tells me the Nest thermostat currently goes for about 3 times the price of the CT100—and the Nest definitely requires an external power source, so running it on batteries isn’t an option.

A brief look at the Nest’s installation guide also suggests that the CT100’s installation instructions, though text heavy, are less ambiguous and more comprehensible.

Of course, as my video makes clear our furnace is pretty basic—so my installation was straightforward.  And the Nest supposedly learns about your heating preferences and will act on its own without requiring your intervention.  Which could be cool.

For the moment, though, I’m pretty happy with the CT100.

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