Radiant ceiling heat is a style of heating a building that relies on thermal radiation rather than convection. While typical furnaces or boilers heat the air in a building, a radiant heating elements applies infrared energy directly to the objects in the building. This makes it useful for workshops and garages. It is also possible to set up multiple heating zones by controlling the radiant ceiling heaters in each room with a single thermostat. Occupants will notice the effects of radiant heat much faster than hydronic or forced air heat. The heaters also cool down faster as well. This flexibility and responsiveness makes radiant ceiling heat a highly energy efficient choice in some situations.
However, radiant ceiling heat is subject to failure just like any other mechanical system. Determining the cause of the problem is much easier if you are lucky enough to have an infrared scanner to locate faulty panels. Some repairs are simple and straightforward. Others are next to impossible, and not economically feasible from a practical perspective. You may have to replace a few parts, or scrap the system altogether.
Step 1 - Check Circuit Breaker
The first step to take when you suspect a problem with the radiant ceiling heat is to check the circuit breaker. Radiant heating elements are wired directly into a 120-volt or 240-volt power supply. If the breaker is tripped, reset it. The heat should start working again immediately. If the breaker continues to trip, the circuit may be overloaded. Have an electrician inspect it further.
Step 2 - Repair Faulty Wiring
If the radiant ceiling isn't heating up because of an incomplete circuit, there are several possible causes. First, check the visible wiring. Begin at the breaker box, tracing back through the walls and attic. Look for corroded or snapped wires. If this is the source of the problem, repairs are fairly easy. Lock out the circuit and replace the damaged wires. Splice in a new cable with a wire crimper or wire nuts.
Step 3 - Replace Burned-Out Heating Elements
If the wires to the ceiling are intact but the heating element doesn't work, it may be burned-out. Use a multimeter to check for continuity across the elements. In older construction, radiant ceiling heat often consisted of wires sandwiched between a layer of drywall and a layer of plaster. When these wires burn out, it is very difficult to repair the system without tearing out most of the ceiling. Modern radiant ceiling heat panels are much more convenient. The panels are modular, so when one breaks, it is easy to unscrew it from the ceiling. Swap out the faulty panel for a new one.
Step 4 - Adjust Thermostat
Radiant heat generally operates in a much larger temperature window because it warms the air slower. To reduce this window, you have two options. Putting the thermostat closer to the ceiling's "line of sight" will make it more responsive. You can also try circulating heat throughout the room by running a ceiling fan or box fan.