Gas log installation sized to your Stoneybrook East fireplace

Minimum firebox size for each burner

Every burner has a smallest fireplace it can go into. In one maker's table, the 18/20 inch burner calls for a firebox no narrower than 26 inches across the front and 20 across the back, at least 15 inches deep and 17 inches tall.

Its 24 inch burner needs 30 inches at the front and 24 at the back, and its 30 inch burner 36 and 29, with the same depth and height. Our crew measures all four dimensions in your firebox and compares them with the table for the set you want.

• Front width
• Rear width, measured at the burner's depth
• Depth from the opening
• Height of the opening

The oxygen depletion safety system

The state fuel gas code requires, in section 621.6, unvented room heaters to have an oxygen-depletion-sensitive safety shutoff system. On vent-free log sets, it is usually built into the pilot, often called an ODS pilot.

One vent-free manual explains that the ODS shuts the heater down if there is not enough fresh air and cuts off main burner gas if the flame goes out. A set that keeps shutting off is telling you something about the air in the room, and our pros never bypass the system.

Fans, drafts and flame patterns

A vent-free flame is sensitive to moving air. One manual warns not to let fans blow directly into the fireplace and to avoid any drafts that alter the burner's flame pattern, and it rules out installing the heater in high traffic, windy or drafty areas.

Ceiling fans, air conditioning registers and doors to the patio can all send air across a firebox. Our crew looks at what moves air around your fireplace and suggests simple changes when a flame is being pushed around.

Walls above a vent-free set

Warm air rising from a vent-free set carries whatever is in the room with it. One manual cautions that installing the heater next to vinyl or cloth wall coverings, or running it where tobacco smoke, scented candles, cleaning fluids or oil lamps are in the air, may cause walls to discolor.

It is a practical point that surprises owners after the first season. Our pros mention it at the planning stage, when the choice between vented and vent-free is still open.

A regulated propane supply

Propane tanks hold gas at pressures far above what a burner can take. One log set maker says the propane source must be regulated, warns against connecting the set directly to an unregulated tank and rules out a portable propane cylinder entirely.

Regulators and tank connections belong to your propane supplier or gas contractor. Our crew checks that the supply reaching the set is regulated and lists any supply work for others on its own line.