removal of existing Frost Thermostat


Hi Newbie here...Hoping you can help. I installed my tado system a month or so ago and all has been working like a dream. This consists of a Wireless Room Thermostat, a wireless receiver and 8 x smart TRVs. As part of my initial install i removed/unwired the existing wall mounted/wired Honeywell Hall Thermostat but left the existing wall mounted/wired Honeywell "Frost" Thermostat that was on the wall next to it. Fast forward to this week and i decided (as all tado kit was working like a dream) to now remove the Frost Thermostat. I contacted Tado to ask how i unwire the frost thermostat and was told to follow the same "unwiring" instructions as i did for the removal of the room thermostat. I did this yesterday evening no problem. However i have woken up today with all radiators ON (that do not have a tado smart trv fitted) - in fact these (non smart) radiators have been on all night ! this cannot be a conicidence and must be to do with the removal of the wall mounted frost thermostat. Any ideas what i need to fix this please? My phone Tado app shows the heating as OFF but all non smart radiators remain ON? Thanks Dan

Best Answer

  • GrilledCheese2

    Without seeing a wiring diagram it’s difficult to know what you’ve done wrong. Frost stats are generally wired in parallel to the the room stat and are normally open. If I had to guess I’d say you’ve connected two wires together permanently, when they should have been isolated.


  • Thank you - yes that did the trick. i needed to isolate two of the wires 😀