tado Error Codes & Diagnostics
Complete diagnostic directory for official tado fault codes. Verify root causes, safe troubleshooting steps, and replacement part numbers before calling a technician.
tado Smart Radiator Thermostat E1 calibration error
tado defines Smart Radiator Thermostat E1 as calibration failure because the closed valve position was not detected. The support path focuses on secure mounting, the correct adapter, adequate batteries, and a valve pin that moves and returns properly. E2 and E4 are different calibration outcomes and should not be merged into E1. Applies to: tado Smart Radiator Thermostat This page follows tado's E1, E2, and E4 radiator-thermostat support article. Hardware generation, mounting bracket, adapter, and valve body vary, so use the instructions for the exact tado device. Owner-safe checks: Use the exact tado mounting guide, fit compatible fresh batteries, confirm the correct adapter and secure head, and never dismantle the water valve. Qualified technician: Leaking, bent, seized, damaged, or uncertain radiator valves, pressurised components, and recurring calibration after correct mounting need heating or tado support.
tado radiator E2 versus E4: no pin contact or too little valve travel
E2 means calibration found no contact between the thermostat motor and the radiator-valve pin. E4 means contact was found but the distance between the detected open and closed positions was too short. E2 starts with mount and adapter geometry; E4 starts with valve-pin travel and battery condition. Applies to: tado Smart Radiator Thermostat V3+ and earlier devices in the cited support flow These meanings apply to tado V3+ and earlier Smart Radiator Thermostats in the cited support article. Display symbols differ on the Basic model, and newer product generations require their own support path. Owner-safe checks: Identify the exact code, check the documented adapter and extender, use fresh approved batteries, and keep all work outside the wet valve body. Qualified technician: Leaking, seized, bent, corroded, or uncertain valve hardware and repeated calibration after correct mounting require heating or tado support.
tado calling for heat with nothing happening: where the demand stops
When a tado control shows a heat demand and the appliance stays cold, the demand is stopping somewhere between the two. The chain runs from the thermostat, through the radio link, to a receiver or extension kit, and finally through a pair of contacts into the boiler, and each of those can fail while the one before it reports success. Applies to: tado smart thermostat systems using a wireless receiver or an extension kit between the control and the heating appliance tado has shipped several generations with different radio arrangements, including the newer tado X range which is not wired or paired like its predecessors. Match the product names on the devices you actually own to the tado support material for that generation before following any instruction. Owner-safe checks: Try to produce heat from the appliance or from any control other than tado, and note whether it works. | Look at the receiver or extension kit and note whether it shows any indication at all. | Write down anything that changed in the property recently, including furniture, appliances, routers, or a relocated thermostat. Qualified technician: Wiring between a receiver and a heating appliance carries mains voltage on United Kingdom installations, so terminal work belongs to a qualified person. | An appliance that produces no heat by any route is a heating fault and needs a Gas Safe registered engineer rather than control support.