An electric fireplace that glows but will not heat: checks in order

Why the flames can work while the heat does not

The flame picture and the heat come from separate parts of an electric fireplace. The flames you see are lighting, LEDs or small bulbs behind a turning rod or a patterned screen. The warmth comes from a heating element with its own fan blowing across it, switched by a thermostat and guarded by a thermal cutoff that kills the heater if the cabinet overheats.

Because they are separate, the flame picture can run perfectly while the heater does nothing. That is useful, because it narrows the search to the heater's supply, its settings and its safety devices. Work through the checks below in order, with the unit switched off and unplugged whenever you are touching anything other than the controls.

Power at the outlet and the breaker

If the electric fireplace is not turning on at all, flames included, start here. Make sure the plug is pushed fully into a wall outlet. The manuals for these units want the plug in a grounded wall outlet, with no extension cord or power strip in between, because the heater's load can overheat them. If the unit is on a power strip, move it to the wall before going any further.

If the outlet has test and reset buttons, press reset. Look at the breaker panel for a tripped breaker. You can test the outlet itself by plugging in a lamp. Some units also have a main power switch on the cabinet, separate from the buttons on the front or the remote, and Dimplex refers to one in its troubleshooting steps; it has to be on for anything to work.

If the outlet is one of those controlled by a wall switch, make sure the switch is on; it is an easy one to miss when the unit sits across the room from the door.

The heat setting and the thermostat

The heater has its own on switch. Where the flame effect can run alone, the heat has to be selected separately with a button, a switch or the remote. Check that the heat is actually selected and not only the flame.

Then look at the thermostat. If it is set at or below the temperature of the room, the heater has nothing to do and stays off. Turn the setting up well above the room temperature and wait a minute. If you use a remote, replace its batteries, and if the unit answers its own buttons but not the remote, the remote may need to be paired with the receiver again, which the manual explains.

A tripped thermal cutoff

The thermal cutoff is a safety device that cuts power to the heater when the inside of the unit overheats. Once it trips, the heat stays off until it is reset. Dimplex describes the reset for its units as switching the main power switch off, waiting 5 minutes and switching it back on. Other makers ask you to unplug the unit for a set time. Follow the steps in the manual for your model.

Find the cause before you reset. Dimplex notes that its cutout trips when the ventilation slot at the bottom of the unit is covered or blocked. Furniture, a rug, a blanket or decor pushed against the grilles can do it. If the cutoff trips again after the airflow is clear, stop resetting it; the same maker advises unplugging the unit and calling for service when it has to be reset over and over.

Dust, lint and pet hair in the grilles

The fan pulls air in through a grille and pushes it out across the element. Dust, lint and pet hair build up on the intake and on the fan blades over time, and a clogged intake both reduces heat and runs the unit hotter inside, which is what trips the cutoff. With the unit unplugged and cool, vacuum the grilles gently with a brush attachment, as the manual describes. Models with an air filter have a filter to clean or replace as well.

Look behind and under the unit as well. Some cabinets draw air in at the bottom or the back, and a unit pushed tight against a wall or sitting on a deep rug can starve its own intake.

Do not take the cabinet apart to clean inside it unless the manual shows you how. The element and wiring sit behind the grille, and cleaning deeper than the manual allows is repair work.

Electric fireplace blowing cold air

A fan that runs while the air coming out is cool points to the fan working without the element. The heat may be set to a low or fan-only mode, the thermostat may be satisfied so the element has switched off, or the element itself may have failed. Some units also keep the fan running for a short time after the heat switches off, to cool the element down, and the manual says whether yours does.

If the heat is selected, the thermostat is set well above room temperature and the air still stays cool for several minutes, the element or its controls need testing. That is a repair, done with the unit unplugged and a meter on each part.

Heat that is weak rather than missing

Sometimes the heater works but the room still feels cool. Check the heat setting first, since units can offer a low and a high setting, and check where the thermostat is set relative to the room. A thermostat that is only slightly above room temperature switches the element on and off in short bursts.

The heater section can only deliver the wattage on its label, and a plug-in unit is built to run from an ordinary household outlet. Placement matters too. A unit set into an old fireplace with the damper open can have cooler air falling down the flue behind it, and a unit near an outside door or a return grille loses its warm air quickly. If the heat is simply less than the room needs, the answer is a larger heat source, not a repair.

Where troubleshooting ends

An electric fireplace not working safely should be switched off and checked if any of these happen:

• The breaker trips each time the heat comes on
• The plug, cord or outlet feels warm or looks discolored
• You smell scorching or hot plastic, beyond the brief odor of first use
• The thermal cutoff trips again after the grilles are clear
• The unit has been wet, or the cord or plug is damaged