Set the cover plate back in its place. Once you get the Battery/Batt Low indicator you will have 60 days to replace the batteries before the device stops functioning. Several non-programmable Honeywell thermostats do not require batteries to power the control unit. Follow the steps in the previous section to perform a thermostat system reboot by turning off the breaker switch. Some models use battery compartments; others require removing the faceplate to access the batteries. Gently pull the cover plate off from the base plate. Daniel founded Smart Home Perfected in 2019 as a personal passion project. Take out the cover and replace the battery. I cant locate a battery to replace any suggestions? Make sure to keep the +ve and -ve terminals of the battery right. This image is not<\/b> licensed under the Creative Commons license applied to text content and some other images posted to the wikiHow website. By using our site, you agree to our. I hear later variants of the ST699 may have the battery fully soldered to the board so before rushing out to buy a replacement, take a close look to ensure you are getting the right cell and that you will be able to remove the old one.Step 5. Sorry, something went wrong. To remove the cover plate, place your fingers at the bottom of the thermostat and pull. Single-stage Programmable Thermostat Support, Pro 2000 Horizontal Programmable Thermostat Support. It did, so garage lights just to see if I'll be ordering another one for the front outside lights. It is not uncommon for the low battery indicator to remain active after changing the batteries. When installing or maintaining electronic devices in your home, make sure to observe the manufacturers instructions at all times. Thermostat Replacement; Thermostat Wiring Compatibility; ToP SEARCHED PRODUCTS 3G Service is Ending in 2022; 1-Week Programmable Thermostat Support; To be notified when this item is back In Stock, please enter your Email Address below: Schedule your home lights with a Honeywell Home 7-Day Programmable Light Switch Timer. Honeywell ThermostatBattery TypeNumber of BatteriesBattery Location1000 SeriesAAA2Under the cover plate2000 SeriesAAA2Under the cover plate3000 SeriesAA2Under the cover plate4000 SeriesAA2Under the cover plate5000 SeriesAA2Battery compartment6000 SeriesAA2Battery compartment8000 SeriesAAA3Under the cover plate. That was easy, right? - Reviewed: 05/30/2016 by CharlesMahjoubian. Energy management timers, 24-hour or 7-day time switches (4 pages) Timer Honeywell ST699 Datasheet. I cant remove the keypad from the wall. Non-programmable systems do not have control panels, and therefore do not require batteries. In my case the PCB has a legend indicating positive is the contact nearest the two black relays.Step 7. Without a functioning control unit, the system will not work. How Do You Reset a Low Battery On a Honeywell Thermostat? Fortunately, the systems that require batteries are not very power-hungry, so the batteries will typically last for a long time. We have been using Honeywell light switch timers for years and find them to be the best: easy to program and great tech service, should you need it. A technician SHOULD be able to tell you which. It is always wise to shut off the mains power to the thermostat system. Some Honeywell thermostats use alkaline AA batteries, while others use alkaline AAA ones. Gently pull the cover plate to separate it from the base plate. Also not sure if it takes AA or AAA batteries but I bought both. It isnt programmable either, but it has other top-notch features. This image is not<\/b> licensed under the Creative Commons license applied to text content and some other images posted to the wikiHow website. The furnace itself is working fine; I know because I have hot water. Put the cover plate back on the base plate. wikiHow, Inc. is the copyright holder of this image under U.S. and international copyright laws. Changing the batteries on a Honeywell thermostat system is quite simple. - Reviewed: 04/03/2018 by Antonio Priester. I change my Honeywell L5200 system battery but the low battery icon still showing after some weeks. Can you tell me which current Honeywell thermostats would be a replacement to the old model T874D1165? Relatively easy for a non- electrician to install. Use three AA, 1.5 volt, alkaline batteries. You can now go ahead and turn your thermostat on.