Floor Overheating
Floor too hot? This is a critical fault that can damage flooring and cause discomfort. Follow our emergency guide to protect your floor.
Emergency Steps - Do This First
Turn Off System Immediately
Switch off the UFH controller or isolate the circuit at the consumer unit.
Close Manifold Valves (Wet Systems)
Manually close all flow meters or isolation valves on the manifold.
Open Windows
Ventilate the room to reduce ambient temperature safely.
Inspect for Damage
Check flooring for cracks, warping, or lifting. Document any damage.
Call Professional
Do not restart system until fault is diagnosed and repaired.
Symptoms of Overheating
Floor uncomfortably hot to walk on
Surface temperature exceeds 27-29°C, causing discomfort when barefoot.
Room temperature much higher than thermostat setting
Ambient temperature significantly overshoots the desired setpoint.
Heating continues even when turned off
System appears to ignore off commands or schedule.
Floor surface damage appearing
Tiles cracking, wood warping, or laminate lifting due to excessive heat.
Thermostat showing error codes
Sensor faults or communication errors displayed on controller.
Common Causes & Solutions
Floor Probe Failure
The floor temperature sensor has failed, causing the system to run without temperature feedback.
Solution: Test probe resistance with multimeter. Replace if reading is outside normal range (typically 10kΩ at 25°C for NTC sensors).
Incorrect Temperature Limits
Maximum floor temperature limit set too high or disabled during installation.
Solution: Access thermostat installer settings. Set floor limit to 27-29°C maximum. Consult flooring manufacturer guidelines.
Thermostat Misconfiguration
Thermostat set to air-only sensing when floor sensor should be primary or limiting.
Solution: Reconfigure thermostat to use floor sensor as limiter. Check sensor type matches thermostat settings.
Actuator Stuck Open
Zone valve actuator has failed in the open position, allowing continuous flow.
Solution: Check actuator operation. Replace if stuck. Verify valve pin moves freely when actuator removed.
Mixing Valve Failure (Wet Systems)
Thermostatic mixing valve stuck open, allowing boiler-temperature water into UFH loops.
Solution: Check mixed flow temperature at manifold. Should be 35-55°C. Replace mixing valve if temperature uncontrolled.
Wiring Centre Relay Fault
Relay in wiring centre stuck closed, keeping zone active regardless of thermostat demand.
Solution: Check relay clicks when thermostat demand changes. Replace wiring centre if relays faulty.
Frequently Asked Questions
Need an engineer?
If this guide points to a fault you would rather not tackle yourself, our REFCOM-registered, F-Gas certified engineers cover London and the M25 with 24/7 emergency callout. Engineer time is £120 + VAT per hour with a written quote before any chargeable parts are fitted. Start with the relevant service below, or contact us for a site survey.