How To Troubleshoot Radiant Floor Heat

Radiant floor heat systems circulate heat through the floor to make the winter warmer. Radiant floor heaters work by either circulating water through under ground pipes or by running electricity through a cabled system. 

However, when you turn them on for the first time after a long summer, you may experience some problems. It is easy to troubleshoot your radiant floor heating system by following these tips.

Adjust Zone Valves

Radiant floor systems have three valves: hot water, cold water, and mixing valve to control water temperature. These commonly between the hot water pipe and the heating coil pipe, or refer to your manual for location. If you aren't getting enough heat, the problem is often the mixing valve not heating at the correct temperature. Adjust the valves until you get the desired temperature. 

Sometimes, the valves can get clogged with debris and need cleaning. Shut off the power, disconnect the valves, and clean the debris. The valves could also be defective and need replacing, which requires working with solder.  If you don't feel comfortable with solder, hire a professional HVAC. 

Inspect the Circulation Pump

The gauges on the circulation pump could cause insufficient heat and reduction in pressure. One gauge reads the temperature of exiting water, while the other gauge records the temperature as the water returns. 

The temperature difference should be between 15 and 30 degrees F. Adjust the temperature so it is 15 degrees Fahrenheit or greater, and test the unit. If that doesn't work, or pressure still drops slowly, you may need to upgrade the tank to better accommodate the system.

Pressure that drops slowly can also be caused by a pipe leak. Check the crawl space or basement for puddle of water, which indicates a leak. Otherwise, lift the section of flooring to inspect the pipe. 

If you notice condensation under the floor or musty smells, it signals a leak. Turn on the pump, let it run, then turn on the waste spigot at the heater base. Shut the pump off, and get the pipes repaired.

Test the Thermostat and Cables

If you aren't getting any heat at all, check the thermostat, The thermostat radiant flooring system regulates voltage going to the cables. Check the thermostat for voltage with a non-contact voltmeter. Also, test the cables in cabled systems, commonly located between the finished floor or subfloor or rough flooring.

A reading of 0 means a breaker has tripped. Use a screwdriver to open the service panel screws, and check for tripped breakers. Tripped breakers commonly shift to the center or opposite the other breakers. 

 If you recently changed flooring, it could interfere with the system temperature. The type of flooring should correspond with the suggested boiler temperature. Contact a company, like Dick Kearsley Service Center , for more help.