The First Fire of the Season: What to Check First

What changes in a chimney over the summer

A fireplace that sat idle from April to October has been open to the weather and to wildlife the whole time. Birds and squirrels look for exactly this kind of sheltered vertical space, and an uncapped flue is an invitation. Leaves and seeds blow in. Humid summer air soaks into old creosote and soot and makes them smell. Freeze-thaw damage from the previous winter shows up as loose mortar or a piece of flue tile that drops onto the smoke shelf.

None of this is visible from the living room. That is why the first fire deserves a few minutes of checking that later fires do not.

Checks before you strike a match

Do these with the fireplace cold and a good flashlight.

• Open the damper fully and make sure it stays open without being held
• Look up past the damper for twigs, leaves, nest material or a blocked view of daylight
• Check the firebox floor and smoke shelf for chunks of tile, mortar or brick
• Remove any summer cover, chimney balloon, insulated pillow or magnetic damper panel
• Test the smoke alarms and carbon monoxide alarms
• Clear rugs, cushions, baskets and decorations from the hearth and the front of the opening

Reading what you find

Twigs or straw packed above the damper mean a nest. Do not try to burn it out; a nest is dry tinder that can catch and burn up the flue, and in some cases the birds are protected. Have it removed and put a cap on. Pieces of orange or tan clay on the smoke shelf are usually flue tile, which means the liner has cracked or spalled somewhere above and the fireplace should not be used until it is inspected. Rust flakes on the damper and a stained firebox point to water coming down the flue, often through a missing cap or a cracked crown.

A clean shelf, a damper that moves freely and a clear view up the flue are good signs, though they do not replace a proper inspection.

The smell of the first fire

Over the summer, dust settles on the grate, the firebox walls and the damper. The first heat burns it off, which gives a short-lived smell much like a space heater switched on in the fall. Old soot and creosote warming for the first time add a smoky, slightly sour note. Both usually fade within the first part of the fire.

A wood stove does the same, often more strongly, because dust sits on hot steel. A new stove, or one with new paint or gaskets, also gives off fumes during its first few burns as the coatings cure. The stove's manual usually describes this break-in period and how to handle it; ventilating the room while it happens is normal practice.

Smells and signs that are not normal

Some first-fire smells point to a real problem. Know these before you light up.

• Musty or rotting smell: often an animal, nest or debris in the flue. Put the fire out and have the flue checked
• Hot plastic or rubber: something in the firebox, or finishes or wiring too close. Put it out and find the source
• Smoke rolling into the room: a blockage, a cold flue or a damper not fully open. Check the damper; if it continues, put the fire out
• Rotten eggs near a gas fireplace: a possible gas leak. Leave the house and call the gas company from outside
• CO alarm sounding: exhaust is entering the room. Get everyone outdoors, then call 911

How to light the first one

A chimney that has been cold for months is full of heavy, cool air that resists the first smoke. Warm it before loading the fire: hold a rolled sheet of newspaper, lit at the top, up near the open damper for a few seconds until you feel the air pull upward. In a tight house, cracking a window in the same room helps the fire get the air it needs.

Then build a small fire of dry kindling with two or three split logs, and light it. Keep the screen or glass doors positioned as your fireplace's instructions direct. Resist the urge to build a big fire to test the chimney. A large first fire on top of a season's leftover creosote is exactly the wrong experiment.

Watching the first half hour

Stay with the fire for the first thirty minutes. Smoke should rise cleanly into the opening, the flames should stay bright, and the room should not smell of smoke after the first few minutes. Listen too: a steady crackle is normal, while a roaring or rushing sound from the chimney itself, or popping and cracking from above the damper, can mean creosote is burning in the flue. That is a chimney fire. Close the glass doors if you have them, get everyone out, and call 911 from outside.

If the fire burns well but the room smells smoky by the end of the evening, make a note. That pattern often points to a draft problem worth raising at the next inspection.

Gas fireplaces and inserts at season start

Gas units have their own first-use routine. Spiders and insects like the pilot assembly and burner ports over the summer, and dust on the logs and burner gives the same short burning smell as a wood fireplace. If the pilot was turned off for summer, relight it following the instructions on the unit or in the manual, and watch that the flame is steady and blue rather than lazy and yellow. Glass on a sealed unit should be clean and properly latched before lighting.

Wood stoves and inserts benefit from a look at the door gasket and glass gasket before the first burn. A gasket that has gone flat or loose lets the stove pull extra air, which makes it run hot and hard to control. The paper test, closing the door on a strip of paper and pulling it out, shows whether it still seals.

When to call before lighting at all

If the chimney has not been inspected since last winter, book that before the first fire. NFPA 211 puts chimneys and fireplaces on a yearly inspection cycle, with sweeping whenever deposits have built up. Call sooner, and skip the fire, if you saw animals going in over the summer, if water came into the firebox, if pieces of tile showed up on the hearth, or if last season ended with smoke problems. A local crew can sweep and inspect in one visit and tell you plainly whether the fireplace is ready.