Everything above the damper is the chimney. Everything below it is the fireplace, and it's the part you look at every day. Dampers seize, firebox mortar joints break down under heat, gas assemblies stop lighting, and some fireplaces have never drafted properly since the day they were built.

Signs you'd notice

Illustrated Apex technician straining to free a seized fireplace damper handle

A damper that sticks, won't seal, or won't open
Cracked or missing mortar joints inside the firebox
A gas fireplace that won't light, or that smells of gas
A room that fills with smoke no matter what you do
Cold air pouring in through the fireplace all winter

What happens on the visit

Illustrated Apex technician using a smoke pencil to test fireplace draft

Diagnose the draft, not just the symptom
Smoke in the room has four or five possible causes and only one of them is a dirty flue. Often it's negative pressure — the stack effect in a tightly sealed house, or a range hood and bath fans winning against your chimney. We work out which one you have before selling you a fix.
Repair or replace the damper
Free up and reseat what can be saved. Where the throat damper is beyond help, a top-sealing damper both seals better and stops the winter draft.
Rebuild firebox joints
Failed firebox mortar gets cut out and repointed with refractory mortar rated for direct flame. Regular mortar in a firebox doesn't last a season.
Service gas appliances
Clean and test the burner, pilot, thermocouple, and logs, and confirm the flue is clear. If we find something outside our scope, we say so instead of improvising.

Why it matters

A fireplace that doesn't draft is a fireplace that puts combustion products into your living room. A damper that won't seal is money going up the flue all winter. And firebox mortar exists to keep flame off the surrounding structure — when those joints open up, that protection is gone.