https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/229696#M46278 <P>Hey there Bob99,<BR /><BR />I'm just checking up on this thread, did you have any more questions or need any additional help?&nbsp;<BR /><BR />Thank you for helping out on this thread, everyone!<BR /><BR />Best regards,<BR />Jeran<BR />&nbsp;</P> Wed, 31 Aug 2022 15:56:42 GMT Jeran 2022-08-31T15:56:42Z https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/179111#M36398 <P>So I fitted the Nest before Xmas last year. Heating system works perfectly. Hot water responds to all scheduled requests but also randomly comes on during the week. Late at night, lunchtime, different days. Cant tie it in to any other activity in the house.<BR />When the water switches itself On, the app tells me it’s “off”. I need to manually switch the boiler off. This has been going on for months to the point where I have removed all scheduled requests and only use Boost requests. I’ve tried going thru “Reset All” several times but it doesn’t change anything.&nbsp;<BR />I feel I’ve investigated this to the point where Ive proven the Nest is faulty and I’m going to return it for a replacement. Having installed this **bleep** thing for efficiency purposes it has cost me money in unrequested gas consumption.&nbsp;</P> Fri, 10 Jun 2022 15:32:49 GMT https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/179111#M36398 Bob99 2022-06-10T15:32:49Z https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/209892#M42113 <P>We’ve had our NEST for 4 years now (2nd gen) and ours has just started doing exactly the same. Hot water randomly comes on but shows off on the thermostat. Solution much appreciated please. Darryl</P> Sun, 31 Jul 2022 09:13:18 GMT https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/209892#M42113 Dazza429 2022-07-31T09:13:18Z https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/210750#M42261 <P>I have a Gen 3 nest recently installed and it also is randomly turning on the boiler to heat the water. The only way I can stop it is to turn the hot water tank thermostat to minimum and this turns off the boiler. I have turned off the the water scheduling and the legionaries bacteria prevention feature and it still randomly turns on. &nbsp; Any ideas how to fix this.&nbsp;</P> Mon, 01 Aug 2022 21:22:03 GMT https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/210750#M42261 Big-Al 2022-08-01T21:22:03Z https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/210764#M42263 <P>I still have the problem. Expect it’s either the Nest hub or possibly an earthing fault in the switching circuit.&nbsp;</P> Mon, 01 Aug 2022 21:23:50 GMT https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/210764#M42263 Bob99 2022-08-01T21:23:50Z https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/210768#M42265 <P>The tank thermostat doesn’t seem to affect my system. Switching seems entirely random. Sorry can’t be more help.&nbsp;</P> Mon, 01 Aug 2022 21:28:51 GMT https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/210768#M42265 Bob99 2022-08-01T21:28:51Z https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/210794#M42276 <P>Have you disabled the bacterial prevention feature?</P> Mon, 01 Aug 2022 22:13:14 GMT https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/210794#M42276 Big-Al 2022-08-01T22:13:14Z https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/210800#M42277 <P>I posted elsewhere on the forums, I got in touch with NEST technical help. It’s early days but disabling the bacteria prevention feature seems to have fixed it for me. But if doing that still hasn’t fixed yours, it’s costly, but the item I replaced before this was the Hot Water zone valve, I convinced myself it was stuck open and therefore sending a signal to fire up the boiler, maybe look to troubleshoot that? My system is “S” plan.</P> Mon, 01 Aug 2022 22:20:28 GMT https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/210800#M42277 Dazza429 2022-08-01T22:20:28Z https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/210808#M42278 <P>It is anew boiler installation so I suspect it is a setup issue, although if there is a fault that would be covered by warranty. I have just gone through the bacterial prevention disable process again and this time I also did a reset so hopefully that will fix it.&nbsp;</P> Mon, 01 Aug 2022 22:44:52 GMT https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/210808#M42278 Big-Al 2022-08-01T22:44:52Z https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/211090#M42327 <P>My system is 20+ years old. There is no anti bacteria feature to disable.&nbsp;</P> Tue, 02 Aug 2022 07:28:40 GMT https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/211090#M42327 Bob99 2022-08-02T07:28:40Z https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/211092#M42329 <P>It’s a 20+ Yr old system. No anti bacteria feature that I’m aware of.&nbsp;</P> Tue, 02 Aug 2022 07:33:11 GMT https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/211092#M42329 Bob99 2022-08-02T07:33:11Z https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/211093#M42330 <P>It’s a good call but it has been replaced in the last couple of years. Maybe time to replace it again. Covered under a maintenance contract so no cost to me.&nbsp;</P> Tue, 02 Aug 2022 07:35:21 GMT https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/211093#M42330 Bob99 2022-08-02T07:35:21Z https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/211099#M42332 <P>Bob99 - it’s a nest thermostat feature nothing to do with the boiler. See link below&nbsp;</P><P><A href="https://support.google.com/googlenest/answer/9256656?hl=en-GB#zippy=%2Cturn-bacteria-prevention-on-or-off" target="_blank">https://support.google.com/googlenest/answer/9256656?hl=en-GB#zippy=%2Cturn-bacteria-prevention-on-or-off</A></P> Tue, 02 Aug 2022 08:05:56 GMT https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/211099#M42332 Big-Al 2022-08-02T08:05:56Z https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/211103#M42334 <P>Bob99, my experience and research, Honeywell may be slightly more expensive but you get what you pay for, far superior. If yours is Drayton, there is a chance that it could well have failed again!</P> Tue, 02 Aug 2022 08:18:58 GMT https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/211103#M42334 Dazza429 2022-08-02T08:18:58Z https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/211104#M42335 <P>Big-Al, two other things they got me to do while sorting mine, turn-off auto-scheduling and erase the hot water schedule and then re-enter it. No idea why but just a couple more things to try before getting the installer back under warranty. Good luck</P> Tue, 02 Aug 2022 08:23:59 GMT https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/211104#M42335 Dazza429 2022-08-02T08:23:59Z https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/211105#M42336 <P>I’ve just read that link and realise now exactly what happened. We had our hot water come on for two hours in the morning and two in the evening. To save money about a month ago I changed them to an hour, which is one of the conditions of bacterial protection. My money saving exercise cost me £96 for a new valve!!……..I’m sure it was about to fail<span class="lia-unicode-emoji" title=":face_with_tears_of_joy:">😂</span></P> Tue, 02 Aug 2022 08:32:06 GMT https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/211105#M42336 Dazza429 2022-08-02T08:32:06Z https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/211110#M42337 <P>Thanks, didn’t realise. Will try and let u know.&nbsp;</P> Tue, 02 Aug 2022 09:25:59 GMT https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/211110#M42337 Bob99 2022-08-02T09:25:59Z https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/211111#M42338 <P>I tried this several times but had no effect.&nbsp;</P> Tue, 02 Aug 2022 09:26:33 GMT https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/211111#M42338 Bob99 2022-08-02T09:26:33Z https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/211116#M42339 <P>I think I have exhausted my sum total knowledge on this subject, sorry</P> Tue, 02 Aug 2022 09:40:14 GMT https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/211116#M42339 Dazza429 2022-08-02T09:40:14Z https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/211117#M42340 <P>There’s only two of us in the house so I set for one hour in the morning and boost later if needed. Bacteria was set on so prob was the root cause of the random triggers. Have set to off now. Will let u know how things go over the next week….unless we are hospitalised with legionnaires of course 🤪. Many thanks for your help.&nbsp;</P> Tue, 02 Aug 2022 09:43:13 GMT https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/211117#M42340 Bob99 2022-08-02T09:43:13Z https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/211118#M42341 <P>Thx anyway. Big Al may have nailed it. Bacteria settings. It’s like a bloody video game with hidden secrets and cookies.&nbsp;</P> Tue, 02 Aug 2022 09:45:29 GMT https://www.googlenestcommunity.com/t5/Nest-Thermostats/My-Nest-Thermostat-randomly-switches-my-hot-water-on/m-p/211118#M42341 Bob99 2022-08-02T09:45:29Z