Shaun Merrigan's Information Pages


Category: NEST Thermostat


NEST Thermostat Network Isolation

Posted by Shaun Merrigan in NEST Thermostat, Ring Doorbell, Tech. Comments Off on NEST Thermostat Network Isolation

6th February

NEST Thermostat Network Isolation

With the proliferation of IoT (Internet of Things) objects such as smart thermostats, sensors of all kings, video cameras, video doorbells, light bulbs, media hubs and the like it comes as no surprise that security problems are cropping up.  These IoT devices are proving to be a door through which malicious software can gain direct access to your home network behind your router.  An excellent summary of the potential security problems with IoT devices can be found here InfoSec Resources Iot Security Summary.   The takeaway is that these devices are vulnerable, and attackers can use them to penetrate your home network.  Once an attacker gains access to the network behind your router, they have the “keys to the kingdom”.  What is the solution?  As usual with home network security, there are several solutions ranging from relatively … Read More »


Nest connectivity and charging problems solved

Posted by Shaun Merrigan in NEST Thermostat. Comments Off on Nest connectivity and charging problems solved

9th November

Nest connectivity and charging problems solved:

I have two NEST thermostats; one first generation and one second generation.  I experienced intermittent connectivity issues with my gen1 Nest soon after I installed it.  Initially I determined that it was not charging properly so I brought out the “C” (AC Common) wire from my furnace control board to the NEST and the charging problem was solved.  When I  installed the gen2 NEST, I made sure the “C” wire was available at installation.  I have no charging problems with either NEST now.

 

Connectivity problems would come and go, sometimes going many weeks or months between incidents.  I tried many solutions (port forwarding .lease times, static ip, etc) with varying degrees of success.  The connectivity problems were irritating rather than debilitating; most of the time the NEST worked fine.  The same pattern occurred after I installed … Read More »


NEST Connectivity Issues Solved

Posted by Shaun Merrigan in NEST Thermostat, Tech. Comments Off on NEST Connectivity Issues Solved

12th October

I have two NEST thermostats, one v1 and one v2. The v1 had been ticking along fine until about July 2014 when I began to experience connectivity problems. More specifically, the thermostat itself would say that it was connected properly,  but the NEST browser and mobile apps would show it as offline. I tried all the usual fixes: reboot, restart, reset, both (router and NEST), static ip, DHCP Leasetime tweaks, etc.  Long story short, nothing I did solved the connectivity issues.

As it turned out, I was reconfiguring my home network and decided to change my main router from a Netgear WNDR4500 to an ASUS RT-AC68U. This change has resolved all my NEST connectivity issues. NEST Connectivity Issues Solved !  Both my NEST thermostats are fully connected and accessible any time I check them. It turns out that the RT-AC68U has … Read More »


Nest thermostat: Should I assign an IP or Not?

Posted by Shaun Merrigan in NEST Thermostat, News, Tech. Comments Off on Nest thermostat: Should I assign an IP or Not?

25th June

Nest thermostat: Should I assign an IP or Not?

The question is: Does assigning the NEST thermostat a static IP using your router result in a more reliable wireless connection?  For my first generation NEST running v4.2.3 of the NEST software, the answer is a definite no.

Background:

I am using my home router as a DHCP  server in order to assign IP addresses to various devices behind it.  This is the typical default behavior of most home routers.  I like to tweak the setup, however and assign static IP addresses to various devices so that troubleshooting is simplified and  IP address conflicts are avoided.

My NEST thermostat connectivity had been generally very good, until a couple of weeks ago when I found that the NEST thermostat could not connect reliably to my router.  (I had updated my router firmware about that time as … Read More »


NEST Thermostat Update and Voltage Measurements

Posted by Shaun Merrigan in NEST Thermostat, News, Tech. 1 Comment

18th November

NEST Thermostat Update and Voltage Measurements

I have had my NEST Gen1 for almost 16 months now and I probably could not go back to a regular dumb thermostat, given the choice.  The NEST charging problem has been solved by connecting the “C” (AC Common) wire from my furnace to the NEST.  See this post for details: Nest Thermostat Charging Solution

I find the monthly NEST Energy Reports very useful, and I am saving them so that when I make important changes to our house (new windows, more insulation, more efficient furnace, etc) I can see an actual difference.

 

I thought it would be helpful to anyone still troubled by the charging problem if I posted my NEST reported and measured voltages:

Furnace running (heating) NEST Reported Voltages: Voc 38.33V, Vin 31.57V, Vbat 3.864V, Lin 100mA (i)

Voltage measured between Rc and C (Power and … Read More »


NEST Thermostat Functioning Well after Wiring Change

Posted by Shaun Merrigan in NEST Thermostat, News, Tech. Comments Off on NEST Thermostat Functioning Well after Wiring Change

16th March

NEST Thermostat Functioning Well after Wiring Change:

Over a month on since I changed my NEST v1 thermostat wiring to include the “C” or 24Vac Common wire, it is working flawlessly again. We have had several cycles of cold (-20C) and warm (+8C) and there have been no problems with charge levels, network communication or connectivity.

I wonder why NEST does not strongly recommend the use of the “C” wire when it is so simple to install? BTW, if you are looking for a wiring diagram of your furnace and controller, check the back side of the access panel (Doh!!) on the furnace; it should be there.

I have e found a couple of very useful links for anyone in a similar situation and seeking a solution:

Adding a C wire to a Thermostat

When-Nest-needs-a-common-C-wire

Shaun M