Troubleshooting a Radiant Floor Heat System

A radiant floor heat system is a popular method used to heat homes and buildings. It works by radiating heat upward from the floor and distributes heat throughout the room. These can work well, but sometimes, you'll need to troubleshoot your system to keep it running. Here are some problems and solutions to try if your radiant floor heat system is not operating the way it should:

See Whether the Valves Work

The 3 ports on the valve (hot, cold and mixing) should have water flowing through them at the right temperatures. When there's a problem with the valve, it's often with the mixing valve. It should supply warm water back to the heater system. If it's not, adjust the valves until you get the correct warm temperature that should be flowing through. Compare the mix temperature coming out with the valve setting to make sure they match. If they don't, replace that particular port.

Check the Tubing

The tubing that's installed in the system can become rusty or moldy, especially if it's made of steel or cast iron. This can block your tubes. It's best to remove those tubes and swap them out for tubing made of ethylene propylene diamine, also referred to as SoloRoll. If these become plugged, it's easy to treat with fungicide or to blow out the plug with compressed air.

Change in Floor Covering

The water temperature for the radiant floor heat system is different depending on the type of floor it's installed under. If you don't match the temperature to the type of flooring, you'll have problems. When you install new floors or change floor coverings, check to make sure the type of flooring you have matches the recommended temperature for your boiler, to make sure the heat system works properly.

Heat is Not Enough

If the radiant floor heat system is not giving enough heat, then you may have a problem with the boiler itself or the water temperature. First, check to see whether your boiler turns on and off in cycles. If it's always turned on, then your boiler is too small for the system. Next, check the water temperature to make sure it's not too hot. For example, if it's above 110 degrees F. and is going to concrete or Gypcrete, it's too hot.

Injection Pumping

There might be an issue with the sensors on your supply and injection pipes if you're using injection pumping, as well as the accompanying outdoor sensors. If the outdoor sensor is faulty, it won't provide the right temperature for the supply water, which could produce low heating or other problems. You can check to see if your sensors are working with a resistor that will compare the ohms reading to the recommended temperatures.