20 Common Underfloor Heating Faults & Errors
Complete diagnosis guide covering every major underfloor heating fault, from cold spots to thermostat errors. Identify symptoms, understand causes, and know when to call a professional.
Jump to Fault
Critical Faults
Require immediate attention
Moderate Faults
Schedule repair soon
Minor Issues
Can often self-diagnose
Complete Fault Reference
Diagnostic Tools We Use
Our engineers use professional diagnostic equipment to accurately identify faults without unnecessary floor damage.
Thermal imaging cameras
Detect heat patterns and locate cable breaks
Multimeter & resistance testing
Check electrical continuity
Pressure decay testing
Identify leaks in wet systems
Flow & temperature probes
Measure water flow and temps
Endoscope inspection
Visual pipe inspection
When to Call a Professional
Call Immediately
- Floor overheating (safety risk)
- Water leak detected
- System repeatedly trips RCD
- Burning smell from floor
- No heat during cold weather
Schedule Soon
- Persistent cold spots
- Thermostat error codes
- High energy bills
- Slow warm-up times
- Gurgling noises in pipes
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.