How Electric Underfloor Heating Works
Heating Element
Electric cables or mats beneath the floor convert electrical energy to heat through resistance.
Thermostat Control
A thermostat with floor sensor monitors temperature and controls power to maintain your set temperature.
Electrical Supply
Connected to your home's electrical system via a dedicated circuit with RCD protection for safety.
When any component fails, the entire system can stop working or develop faults. Below are the most common electric underfloor heating problems we diagnose and repair.
Common Electric Underfloor Heating Faults
Click each fault to learn about symptoms, causes, and our repair solutions
Heating Cable Break
Symptoms
- •Complete heating failure in affected area
- •Partial floor heating
- •System worked before floor work
Common Causes
- •Damage during flooring installation
- •Furniture leg puncture
- •Cable wear over time
- •Incorrect installation
Our Solution
Our engineers use specialist equipment to locate the exact break point and perform targeted repairs without replacing the entire system.
Learn more →Thermostat Failure
Symptoms
- •Display not working
- •System not responding to temperature changes
- •Erratic heating patterns
- •Error codes showing
Common Causes
- •Electrical surge damage
- •Battery failure (wireless)
- •Sensor malfunction
- •Programming corruption
Our Solution
We diagnose thermostat issues, replace faulty sensors, and install new thermostats compatible with your system.
Learn more →Cold Spots on Floor
Symptoms
- •Uneven floor temperature
- •Specific areas remain cold
- •Rest of floor heats normally
Common Causes
- •Cable spacing issues
- •Insulation problems
- •Localised cable damage
- •Incorrect mat sizing
Our Solution
Using thermal imaging, we identify cold spot causes and recommend the most cost-effective repair approach.
Learn more →Tripping Circuit Breaker
Symptoms
- •RCD trips when heating activates
- •Intermittent power cuts
- •Burning smell (urgent!)
Common Causes
- •Moisture ingress to cables
- •Damaged cable insulation
- •Overloaded circuit
- •Faulty connections
Our Solution
We perform insulation resistance testing to identify faults and make safe, compliant repairs.
Learn more →High Energy Bills
Symptoms
- •Unexpected increase in electricity costs
- •System running constantly
- •Floor not reaching temperature
Common Causes
- •Poor insulation beneath system
- •Thermostat sensor issues
- •Incorrect wattage for room size
- •Heat loss to substrate
Our Solution
We assess system efficiency, recalibrate thermostats, and advise on insulation improvements.
Learn more →Floor Overheating
Symptoms
- •Floor too hot to walk on
- •Damage to floor covering
- •Thermostat shows normal temperature
Common Causes
- •Faulty thermostat sensor
- •Incorrect sensor placement
- •Wrong thermostat type
- •Runaway heating element
Our Solution
Emergency inspection and thermostat replacement to prevent floor damage and safety hazards.
Learn more →DIY Checks vs Professional Repair
Safe DIY Checks
- Check thermostat settings and batteries
- Verify circuit breaker hasn't tripped
- Check isolation switch is on
- Reset thermostat to factory settings
Requires Professional
- Any work involving electrical connections
- Locating and repairing cable breaks
- Insulation resistance testing
- Thermostat replacement/wiring
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.