Downdraft Repair

A modern home can be too tight for its own fireplace. When exhaust fans, the dryer, and the HVAC pull a sealed house negative, the fireplace and other combustion appliances can't get the air they need — so they draft poorly, spill smoke, or backdraft combustion gases into the living space. Texas Service Experts diagnose and correct these combustion-air and makeup-air problems at the level of the whole house, not just the firebox — which is exactly the kind of problem a one-crew, whole-home outfit is built to catch, because we're already looking at how air moves through your ducts, vents, and fireplace as one system. The result is an engineered fix for an invisible, sometimes dangerous, problem.

The symptom looks like a chimney problem but usually isn't. A fireplace that smokes only when the kitchen hood runs, a flue that drafts fine on a calm day but spills when the house is buttoned up, a basement appliance that backdrafts in winter — those are makeup-air problems. The house is depressurized below what the flue can overcome, and air (and combustion gas) flows the wrong way. Pinning it down means putting the house into worst-case depressurization — closing doors, running every exhaust device — and measuring whether the combustion appliance zone (CAZ) still drafts or spills. Skip that test and you're guessing, and guessing about backdrafting combustion gas is dangerous.

The correction matches the finding. If the fireplace itself is starved, we run a dedicated outside-combustion-air (OCA) intake to the firebox so it draws makeup air from outdoors instead of the room — designed in, not bolted on. If the whole house is the problem, we add a passive makeup-air opening or, where exhaust loads are heavy, a motorized makeup-air damper interlocked to the range hood or dryer so the house can't depressurize the combustion zone when those run. Where return-duct leakage is depressurizing a zone, we seal it. The right fix is the one that addresses how your particular house loses its balance — which is exactly the kind of whole-home view one crew brings.

A particularly common version is the orphaned water heater. When a high-efficiency furnace is installed and switches to sidewall PVC venting, it often leaves a lone water heater venting into an oversized common flue it can no longer keep warm — so that flue stops drafting and the water heater spills CO. We re-line and resize the flue to the single appliance so it drafts safely. This is a CAZ failure hiding as a venting problem, and it's exactly the kind of cause-level diagnosis you catch when one crew sees the furnace, the water heater, and the flue as parts of the same house.

The verification standard here is the same as on our CO work: after the correction, we re-run the worst-case depressurization test to confirm the CAZ now drafts and doesn't spill, and we document the result. A makeup-air fix that isn't re-tested under worst-case conditions is unverified — and when the failure mode is combustion-gas spillage, unverified isn't acceptable. The measured before-and-after is the deliverable.

TSE performs combustion-air and CAZ correction across the DFW Metroplex and the major Texas metros to one instrument-based standard. Home tightness, climate, and exhaust loads vary widely; the diagnostic and verification discipline is constant — and because the same crew also handles your ducts and venting, the fix is coordinated across the whole air system rather than handed off. We document the testing so the result is verifiable for you and your insurer.

This work protects health and makes the fireplace genuinely usable again — no more smoke when the hood runs, no winter backdraft, no orphaned appliance spilling CO. If your fireplace or appliances draft inconsistently, or you've had unexplained spillage, it's very likely a makeup-air problem worth measuring.