Filtrete WiFi Thermostat

Much to my wifes chagrin, I recently purchased yet another thermostat for the home. Our house came with a pretty standard analog style thermostat originally, and after wanting something a tad more ‘tech friendly’, I previously opted for a Home Depot purchased Honeywell touch screen unit. This worked well, but when I discovered the WiFi enabled thermostat from 3M Filtrete, I had to replace it. This was my second foray into thermostat work for the home so I was feeling pretty confident overall in my ability to replace my home unit for the second time.

Please note that I am not an electrician and if you do electrical work incorrectly or disregard any packaging warnings or instructions, you can seriously damage your home HVAC equipment, generally cause electrical home mayhem including tripping circuit breakers and blowing fuses, or cause bodily harm – including death. Do not attempt this unless you’re a savvy electrical type of person and always follow the included safety advice of the product. I recommend you starting this project early in day. In the event you screw something up, you want a window of time during the day that an electrician can help you out!

Now that’s out of the way, you could understand my interest in tying my thermostat into my home wireless network. 1) it’s cool (no pun intended) and 2) think of the possibilities! As it turns out, 3M Filtrete have a relationship with the folks over at RADIO THERMOSTAT to provide the cloud based services to control your home climate from any Internet enabled device – including your phone! After a quick check of the wireless device capabilities and a confirmation that it does indeed support WPA2/AES encryption (albeit PSK only), it was a quick trip to the local Home Depot to pick one up! Those of you out of range of a local Home Depot can conveniently have one shipped to you if you’re interested. The packaging was a pretty traditional ‘hard to open’ plastic clamshell that required some cutting and cajoling to get open:

After some separation of the various bits and pieces, I got a good look at the back of the thermostat which is where the radio module gets installed. This is a ‘standard’ thermostat that has two UNSAP (Utility Smart Network Access Port) radio module slots on the back of it and the WiFi module is actually a separate modular piece:

After digging into the installation directions, there were a few things of significant note: 1) There are a variety of HVAC types of systems and 2) There is no formal standard for wiring them. This means you have to be very diligent about observing the existing cabling from your current thermostat. You should turn off the breaker to your existing HVAC at this point since you’ll be plugging and unplugging live wires. After confirmation that the power to your HVAC is off, you will have to open up your existing thermostat and observe the markings on it to determine and label the wires correctly:

Use the included labels to match up the colors marked on your old thermostat. This is arguably the most intensive part of the whole project. You don’t want to get these wrong and I suggest you take pictures along the way as a reference point in case you have to call an electrician to help you out. Once you’ve labeled all of your existing cables, you can physically remove your old thermostat and begin attaching the new one. This is a matter of lining up your previously labeled cables with the connectors across the top of the unit:

It’s also worth noting that the power to the thermostat must be provided via the ‘C wire’ to power the WiFi radio. If you do not have a C wire, you will need to run a dedicated power source for the thermostat. At this point in the install, if you’re confident that you’ve got it all hooked up correctly, go ahead and install the radio module into the back of the unit. The power to the unit needs to be off to install the module so do it now, or wait until you flip the breakers and install batteries to test it, then turn it back off later to install the module. Wrap the cables across the top channel of the module and affix it to the wall using the included mounting hardware:

Once you remove the protective cover, install the batteries in the bottom of the unit and switch the power back on! You’ll have to run through a small setup to bring the thermostat online and before you move on with configuring the RF module, make sure your unit turns on your heater and AC by following the directions in the installation manual. Once you’ve confirmed it works, install the snap-in covers to hide the wires and batteries and move ahead to the fun part – the wireless setup!

The easiest way to describe the wireless setup is that the radio comes preconfigured with it’s own SSID to attach to, it’s own DHCP server, and a PIN based authentication that is displayed on your thermostat screen. Goto the Radio Thermostat site and create yourself a user account. If you have an iPhone, download the free app from the App Store. The app prompts you to log using your Radio Thermostat credentials, then prompts you to join the SSID hosted by the thermostat (wow, there’s something I never thought I’d type!). You then switch back to the Application, configure the unit to connect to your home wireless (SSID and encryption keys), then enter the PIN displayed on the thermostat to complete the setup.

Once your thermostat is online it does all of the cool things you’d expect it to – it auto updates it’s firmware, sets the time based on NTP and your timezone and then allows you to log into the Radio Thermostat page to create your heating and cooling schedules as well as perform instant changes such as setting away from home, turning on cool/heat, turning on or off the fan, etc.

In all, the installation was fairly painless and intriguing overall. Those of you interested in the wireless capabilities of the unit, it is a 2.4GHz radio that supports 802.11b/g data rates, open SSIDs, WEP, or WPA2 security. Here is what my unit looks like from a Cisco AP:

Those of you wondering, no, the unit does not support CCX. 🙂 I’d strongly advocate anyone that’s not afraid of minor electrical work, and appreciates a good overall WiFi enabled, cloud application give this a try. The effort was very doable and those of you that are afraid of cloud controlled HVAC deployments rest well knowing that the radio module is removable. The thermostat functions as a ‘regular old thermostat’ without it and you can remove it at any time.

Cisco WLC 7.2 FUS code release

Cisco recently released version 7.2 of their Wireless LAN Controller code. Along with this update came something new for several administrators in the form of an ‘FUS’ update. This update is available for the 5500 , WiSM 2, and the Flex 7500 platforms and contains a variety of firmware specific updates for each platform including:

  • For the 5500 and WiSM2
  • Field Recovery image update
  • Bootloader updates to 1.0.16
  • Offline Field Diagnostics to version 0.9.28
  • USB Console to 2.2
  • MCU image update too 1.8 (5500 only)
  • FPGA update to 1.7 (5500 only)

For the Flex 7500 controllers, there is a RAID firmware update. There is no FUS update for the 2500 controller or any of the legacy platforms (they’re not supported in release 7.2 in general anyway). Buried in the release notes are a variety of nuggets, but it is imperative that this update be installed by itself with a reboot between it and the main 7.2 code release. The order is not important, just the fact that there is a reboot in-between. Additionally, in order for the FUS image to actually update the various components, you need to have a serial attachment to the WLC during the reboot and you must interact with the image upgrades in order for them to execute. This means that if you’re used to doing the ER updates that you just ‘apply and forget’, this is going to be a deviation from that process. To add to this, each update requires you to answer ‘yes’ in order happen but they’re not quick. You will end up burning somewhere south of about a half an hour to pull off a complete upgrade and if you happen to miss one, you’ll have to reupload the image and step through it again. Cisco is nice enough to tell us during the update approximately how long each will take and these numbers are fairly close to what I’ve experienced in the field. The tally on a 5500 is:

Upgrade Bootloader from 1.0.1 to 1.0.16

  • Erasing Flash (estimated 6 seconds)
  • Writing to Flash (estimated 41 seconds)
  • Checking Boot loader integrity (estimated 2 seconds)
  • Total: 49 seconds

Upgrading FPGA from rev 1.3 to rev 1.7

  • Upgrade takes about 75 seconds to complete

Upgrading Env from rev 1.6 to rev 1.8

  • Upgrade takes about 4 seconds to complete

Upgrading USB from rev 1.27 to rev 2.2

  • Upgrade takes about 11 seconds to complete

Upgrade OFD from version WLCNG OFD 0.8.1 to WLCNG OFD 0.9.28

  • Erasing Flash (estimated 24 seconds)
  • Writing to flash (estimated 111 seconds)
  • Total: 135 seconds

Upgrade Field Recovery Image from version to

  • Erasing Flash (estimated 49 seconds)
  • Writing to flash (estimated 716 seconds)
  • Total: 765 seconds

Yes, you read that correctly – the Field Recovery Image takes a whopping 13 minutes to execute! Of interest to those of you that use the USB serial console built into the WLC is the fact that the USB update will flat out break your session. Once you kick off that particular update, you should suspend you session and wait for it to complete. The kicker of course is that you won’t know since you don’t have a console session. The lesson here is that while it is possible to perform these updates using the USB console, you’ll not regret preferring the good old fashioned RJ-45 console cable method.

If you happen to miss an update and have to reapply the image, you’ll notice that the FUS image will proactively check to see if the updates have been applied already:


Checking for Bootloader upgrade

Bootloader upgrade …

Bootloader 1.0.16 is up to date.


Checking for FPGA upgrade

FPGA upgrade …

FPGA image is up to date

It will perform this check for all components, but when it gets to the Field Recovery Image, it will actually ask you if you want to re-apply it:

Field Recovery Image upgrade …

        Field recovery image Current version is up-to-date.

        Answer “y” below will force upgrade to run again.

        Are you sure you want to proceed (y/N) ? n

Again, note that if you re-apply this particular update, you’re in for a thrilling 13 minutes of ‘edge of your seat’ thrills while it completes. There is no way to cancel it and as you’re warned numerous times throughout the FUS process in bad english:

      * Lost POWER will completely kill this unit and not recoverable. *

      * There may be multiple reboot. Please let the program run.      *

Once you’ve completed your updates, and you’re observing the production image boot, it will verbosely tell you what the version of all of these components are so you can tell that they’ve been successfully applied or not:

Cisco AireOS Version

Firmware Version FPGA 1.7, Env 1.6, USB console 2.2

Initializing OS Services: ok

Applying these updates is important and does resolve a variety of issues so it is recommended to go through whatever outage window you’re going to require to apply them or you may want to consider pulling a spare (+1) controller out of service, upgrading it and moving all of your Access Points over to free up your primary for upgrade. Either way, you should do this – just make sure the updates actually apply!