King Electric Atmoz Wifi (Archive) V3.1-OTA TH1250WF Line Volt Thermostat Tear Down And Quick Review.. 
Let Me Save you Some Reading Time.. This Thermostat Currently is a Big Waste of Time and Money.
If You Want to Use The App and Smart Home Features There May Be a Undisclosed Privacy Risk!
So Far this Device as a manual thermostat is good. but as for the Android App Atmoz and Atmoz 2 is a major failure..
It looks to be a server issue with King Electric’s Smart Home Data Partner Ayla Networks More on that Down Further!!!
Read More If You Wish..
Powered Up.. Has A Nice Display..
As it Was Out of the Box.. 
To Open it it is just one screw you have to open it to be able to mount it on the wall. Yes there is a Non Attached Cover that goes between boards. Removed for Photo. PCB Marked TH1250PWF-V1-1807
Back Side Of Power Board Held In with 2 Small Screws. Again Mixed House Brand Capacitors.. I Did Not Bother Removing the Front PCB Yet. I Will Later and Get the Display Info. The Switching Relay is a 24V 16A SCHRACK – TE CONNECTIVITY RT314024 So it may last a while.. I would really like to see a 20A Here though.. 
Wi-Fi Card is an AMPAK WSDB750GN WiFi-MCU Module FCC Data & User Manual Local Archive
10/29/2025 From the FCC Internal Photos it appears to be a 25L1608E under the shielding I will do a backup attempt of the wifi module would like to do it externally but may have to remove the shielding to do so. (10/30/2025 This is a Custom Module 2 Castellated boards solderer togather) 
MCU is a Renesas Technology Corp RL78/L13 R5F10WMCA (Data Sheet)
11/30/2024, It Looks like My Segger Flasher 5 Pro Supports this MCU But with Renasas its probably locked with a code or security bit. When i get a chance I will attempt a backup. 
Pin out Form Data Sheet Looks Like Pins 9 is TOOL0 and Pin 10 is Reset CON2 is where they to Tool0 Pin 3 / Reset Pin 4
Looking at the Segger Flasher Pro Configuration for the Device I do not see any type of flash ID just a General Security Bit, SO If the Security is not active we should be able to get a read in system. 
Decoding The MCU Info.
R = Renesas
5 = MCU
F = Flash
10W = RL78/L13 Group
M = 80-pin
C = 32KB Rom
A = Consumer applications, operating ambient temperature -40°C to 85°C
Figured they Would Have Used A Code
G, L = Industrial applications, operating ambient temperature -40°C to 105°C
Or Even Better
K, M = Industrial applications, operating ambient temperature -40°C to 125°C
Y = Industrial applications, operating ambient temperature -40°C to +150°C
Jumper Locations And Some Other Connectors! CON2 Is MCU Programming Header 
CON2 Pinouts (Pin 1 has the box around it.)
1 VDD
2 GND
3 TOOL0
4 RESET
Update 10/29/2025 a little bit more reverse engineering time! Ticking away the hours.
I Did some more studding on this device since it is now a necessity to repair it now that king electric manufacturing broke it.
Info from probing around.
Con3 (Appears to be Serial UART) I may have to hook it up to see if I can get a terminal. but the signals appear to be serial.
1 VDD 3.3V
2 RDX?
3 TXD?
4 GND
Con4 (Appears Wifi Programming Header or Another UART / Debug?) No it was another MCU!!
1 VDD
2 SWDIO?
3 CLK ?
4 RST ?
5 GND
10/30/2025 Something did not look right.. So I took the board out to see the reverse side and investigate a little bit further as I could not trace out the pins to the wifi module or mcu.
when i Pulled the board found another MCU hidden under the display… 
STM32F030C8T6 that Explains the Signals above on connector 4 Ill trace it out. This is probably where all the cheesiness spyware is!! The FCC info did not show this to have an MCU. This must be some soft of custom board. with the wifi module on the top. 
I will give it a look with the Xeltek ISO1 o the Segegr Flasher Pro attempt a backup but it’s prob locked! 
Sept 2025, The weather is getting cooler and its time to tun the heat on and no Wifi Control!
I had some extra time so I wired this unit up to attempt a backup with the Segger Flasher Pro / Portable Plus.
I went cave man as I did not have any 2.00mm strip headers handy. 
Looks like I should’ve read a little deeper into the R5F10WMCA datasheet. Turns out the RL78 Series chips can’t just be read with a regular in-system flash programmer Just Erase, Program, & Verify. The RL78 Series need an E2 emulator/debugger and a bunch of extra setup. Plus, debugging has to be enabled and the debug monitor installed which probably isn’t the case here.
There are some reverse-engineering tricks out there, but they can be risky and even destructive to the device. I checked the device lists for my Xeltek, BPM Microsystems, and Data I/O programmers, but no luck none of them support an off-board parallel read. So doing something like I was able to do with the Hakko FM-203 firmware recovery is off the table. That said I still have another backup target, the Wi-Fi card! I believe it uses a 25L1608E serial EEPROM from the FCC Data I looked at with the shield removed. I’ll have to take a closer look and see if there’s an external way to back it up since the shielding is soldered on. not sure how much further I want to go.
For what they are charging for these I would think that would go with Name Brand Capacitors but Nope!! Cheap House / Generic Brands! Yes Brands Multiple. 
The App’s are Broken!! The apps will Install and Allow you to Sign Up and you will get an e-mail. But the E-mail is Not Complete!! The Link is there but hidden Missing image or Text.. So the link is Hidden below the Activation / Verification Code See 2nd Image. 
When you Click empty space to trigger the link they sent from your device on the E-mail The Link Launches the App and Will not take Password says it is wrong. 
This is the Link.. IN the Browser..
“https://app-launcher.aylanetworks.com/launch?custom_url=kingI-th1250wf://user_sign_up_token?token=%5B%5Buser_confirmation_token%5D%5D”
The web browser that open gives a 500 Error…
“{“error”:{“code”:”500″,”message”:”500 – Internal server error. The server encountered an internal error or misconfiguration and was unable to complete your request. Please contact the server administrator, admin@aylanetworks.com, and inform them of the time the error occurred. More information about this error may be available in the server error log.”}}”
Atmoz 1 app Will let you log in with a Gmail account But the Atmoz 2 app will Not it gives an Error, And the Face Book Connect Is Broken on both.
The to Enable the Alexa Skill it requires you to link your account Ayla Networks. “Not King Electronics” Via Ayla Networks (Sign in Link) !! King Electric and Ayla if you cannot complete the Sign Up process for an account you cannot link your account to the Atmoz Alexa Skill..
Ayla Networks Phone # Just Goes o Voice Mail..
King Electronics Also Just Goes to Voice Mail..
Facebook Both No Answer..
NO TECH SUPPORT Evening or Weekends = Bad!! I can get a 6.00 China Smart Wifi switch and if there is an issue a Facebook or twitter Response is min’s away..
I was able to get in but it took a little work figuring out and editing their link from a closer inspection of the HTML Above e-mail on a PC.. (%5B%5B) was replaced with (avhx4FFu) your code will be different..
“https://app-launcher.aylanetworks.com/launch?custom_url=kingI-th1250wf://user_sign_up_token?token=avhx4FFu”
You have to do this for both apps.. I am not sure why? it makes it way to complex..
I hope the above and the following helps people having issues.. A Person should not have to spend an entire Saturday messing with something trying to figure out why Aylan Networks and King Electric have these errors!
Update: 9:08 PM I am Still Trying to Link the Alexa Skill But Now Account is Locked.. I Guess To many Log In Attempts LOL… 
Ok, I have Insomnia!
It 10:45 PM I have Connected to Atmoz (1) App, I was able to validate and Log In by making my own link from the e-mails.
I was able to Enable the Alexa Skill and Connect to the Ayla Networks.
I was able to Get Alexa to Discover the Device! Alexa
Another Issue. The Reset Button on the Side Would NOT Reset the Wifi to Default.
I had to turn off The 1st Router I connected to under my Gmail Login, Reset the Device, Connect Wifi Direct to The Atmoz, and Connect Phone to another Internet Enabled router to be able to login and have the Atmoz app discover the device. Then plug the Main Router Back in, and Set it Up!!
This software is buggy as hell.. Way over complicated!! I hope I do not have to go thru this much hassle to reset the wifi again if I change a SSID or Want to Connect to another network.
After this experience there is No way would I would pay the price because of the poor build quality, poor software, complex setup, and!!
The Other Big Thing!!
That King Electric is outsourcing the Data Custodian of these Devices to Ayla Networks which is worrisome has me wondering if Ayla Networks can be trusted with the meta data collect from the app.. Here is their (Privacy Policy) Do a google search ayla data collection and sales.
I had to learn this without any upfront disclosure on the King Website, Catalog Page, Printing on the Box, or on the google play app page. All the photo’s say Atmoz by King.. it should be disclose upfront that Ayla Networks handles the data not King. What is funny in their November 7th What’s New “Fix Password Error Message For Registration”.. Nope King You Did Not Fix It!!
As of Now With The King Line Volt Wifi Thermostat Do Not Walk But Run Away or Just Buy the K702E-2 SIMPLSTAT or One of the other Wifi Choices. For Line Volt Thermostats
Update: 09/2021
This thermostat has major bugs #1 is it will loose it s settings and the heater will come on unexpectedly, Will not hold set temp if using the panel controls but will if using the app. Still searching for an affordable alternative.
Update 11/30/2024
King Just Killed These Off!
Atmoz-EOL-Customer-Letter-2024
Update 09/11/2025
Progress With King Electric.. the Right to Repair Schematics, and Firmware. I spoke with a Brad Wilson VP of the company. We discussed the right to repair and possible solution to the Atmoz thermostats wifi connectivity being disabled. There may be hope for the Atmoz owners.
09/17/2025 Brad Wilson sent some illegible UL paperwork thinking it would be OK for the documents part.. They are not legible a total slap in the face!
Pages from ATMOZ UL Report 160726126GZU_CDR_V4 .2-1
October 13th 2025 Wife complained it was cold so I turned the breakers for the heating system on within about an Hour i received an e-mail form Alya Systems that the account has been deleted.
October 15th 2025 Wife has a hard time seeing and using these thermostats in manual mode So, I made sure king was aware and that we needed to get this resolved! 
All I received the crickets so I pushed a little harder we needed to get this resolved or I was going to escalate this to small claims court.
The reply was Basically he said I was threatening and cyber bulling and just flat out rude and disrespectful. He Never did send the replacement units as he insisted he would back in September
He again I feel Mocks My Wife Disability!
This is the message that sealed the seal for the escalation was the 2nd time he made comments like this.
10-31-2025 the Discussions Stalled and This Situation has Escalated into a Law Suit. I don’t like it when people break my stuff.
I will still attempt to try and negotiate a resolution that benefits EVERYONE who owns these ATMOZ Thermostats it’s not about the money, it’s about the principle of ownership. I don’t think they will negotiate in good faith so this will most likely go to trial. The 1st court date is December 8th 2025 that’s the order to go to mediation. I will stream it all or post on my youtube channel.
If you’re located in Vancouver, WA and have Atmoz thermostats, I’m willing to help you file a small claims suit against King Electric Manufacturing Co. I may even cover your filing fee and process service costs upfront “only pay back if ya win and are awarded court costs” let me know your story!
You can reach me at kesc @ stevenrhine.com Use Subject: King Electric Small Claims or it will go to a black hole.
Last Updated on November 3, 2025 by Steven Rhine