Home / Troubleshooting / TH115 Floor Heating Thermostat Does the TH115 Floor Heating Thermostat have GFCI Built In? TH115 Floor Heating Thermostat Yes, the TH115 has GFCI built in. Underfloor Heating Thermostats Heated Floors Further Questions? Installation Installation of the floor sensor probe of the TH115 Floor Heating Thermostat What if my TH115 Floor Heating Thermostat says system is on however the floor is not heating up? Why does my heater have a ground wire but the thermostat has no terminal for ground? Troubleshooting What if my TH115 Floor Heating Thermostat says system is on however the floor is not heating up? What if my TH115 floor heating thermostat is not turning on? TH115 Floor Heating Thermostat Error Message: LO TH115 Floor Heating Thermostat Error Message: HI My Floor has No Heat but There Are No Error Messages? Does the TH115 Floor Heating Thermostat have GFCI Built In? How to Fix TH115 Error Message: “ER” Floor Heating Thermostat Programming TH115 Floor Heating Thermostat Error Message: LO TH115 Floor Heating Thermostat Error Message: HI Does the TH115 Floor Heating Thermostat have GFCI Built In? How to Fix TH115 Error Message: “ER” Floor Heating Thermostat Miscellaneous questions Does the TH115 Floor Heating Thermostat have GFCI Built In? Why does my heater have a ground wire but the thermostat has no terminal for ground? Wiring Why does my heater have a ground wire but the thermostat has no terminal for ground?