Wood Burning Fireplace Grate Heaters:

Fireplace grate heaters (aka) hearth heaters can dramatically increase the heat output of your current fireplace without the expense of a chimney liner.

A fireplace grate heater system typically consists of a series of C-shaped steel tubes which are designed to increase the efficiency of a fireplace by adding a convective component to the heat output. The idea behind this approach is straightforward. When a fire is built over the lower section of the tubes, heated air in this section expands, causing an upward flow through the tubes. The simplest tube heater designs rely solely on the natural flow of heated air to move warm air into the room. A more effective system, however, is obtained by adding a fireplace blower to force out a greater volume of heated air.

To be effective, a non-blower model must be positioned so that the upper ends of the tubes are flush with the fireplace opening and within 2 inches (5 cm) of the top of the fireplace. Such placement will force the heated air far enough into the room to prevent it from being sucked back into the fireplace with the combustion air. A non-blower, when used with a glass door, can increase the heat output of a fireplace by 50 percent.

Blower-equipped tube heaters come equipped with a manifold fastened to the lower tubes with a flexible metal hose leading to a remote fan and motor, or with both motor and fan mounted directly on front of the heater tubes. Both styles require a nearby electrical outlet. Blower-equipped heater tubes can double the heat output of a fireplace.

When buying a tube heater, pay close attention to the quality of construction. Look for units with heavy gauge or stainless steel pipes. Lightweight units will burn out quickly. On blower-equipped units, turn on the fan to check the noise level and air output. Blowers need to have a capacity of at least 100 cubic feet per minute (cfm) to be effective; but the larger the blower, the noisier it will tend to be.

Fireplace heater systems come in a wide variety of forms and size. Be sure to choose one that matches the type and dimensions of your firebox or fireplace opening.