Level 1 sweep and inspection to the NFPA 211 annual standard - flue, crown, cap, and flashing checked and photographed
Chimney sweep logs do not sweep chimneys. They loosen some creosote - which then falls where a brush and vacuum still have to collect it.
Olympia Chimney Damper Repair: The Ashburn Owner’s Guide
Olympia Chimney damper repair in Ashburn typically runs $280-$450 installed for a standard throat damper replacement, and we stock the most common Olympia Chimney-compatible parts on our trucks. Most Ashburn homeowners who call us notice the problem first as a draft they cannot close or a damper handle that spins without catching. Russell Haines and our crews have replaced these in everything from the older colonials near One Loudoun to new construction along Loudoun County Parkway, and the failure pattern is usually the same: the cast iron frame outlasts the steel plate and linkage by a decade or more.
Which Olympia Chimney Models This Applies To
Olympia Chimney manufactures throat dampers in several series, and the critical detail is whether your fireplace has a standard rectangular throat or the wider opening found in some of their builder-grade units from the early 2000s. The model plate is usually stamped on the damper frame itself, visible from the firebox with a flashlight, or on a metal tag above the lintel. We most often see the OCM-24, OCM-30, and OCM-36 series in Ashburn homes, though the OCM-42 appears in the larger family rooms common in Brambleton and Loudoun Valley Estates.
Here is the compatibility gotcha: Olympia Chimney changed their pivot-pin diameter in 2008. A post-2008 damper plate will not seat correctly on a pre-2008 frame, and the difference is three-sixteenths of an inch, easy to miss if you are ordering by eye. We carry both pin sizes and the hybrid bushings that sometimes bridge the gap. For OEM, we source direct from Olympia Chimney’s distributor network; for faster turnaround or discontinued models, we use professional-grade aftermarket equivalents from Gelco and Famco that match the original spec without the original markup. Hearthstone Chimney Co. is an independent service provider, not affiliated with Olympia Chimney.
Signs Your Olympia Chimney Damper Repair Is Failing
- The handle turns but the plate does not move. The linkage between the handle spindle and the damper plate has corroded or the cotter pin has sheared. In Ashburn’s humidity swings, this rusts through faster than owners expect, especially if the chimney cap has been missing or damaged.
- You feel cold air dropping even when the damper is “closed.” The plate has warped or the frame has developed a gap. Olympia Chimney’s cast iron frames rarely crack, but the steel plate can bow from repeated heating cycles, and a 1/8-inch gap is enough to lose significant conditioned air up the flue.
- The damper is stuck fully open or fully closed. Debris, creosote buildup, or a failed spring has jammed the mechanism. We see this often in Ashburn homes where the chimney has not been swept in three or more years, the creosote hardens against the plate edges.
- You hear rattling or flapping when the wind blows. The plate has detached on one side and is hanging by a single pivot. This will worsen until the plate drops into the firebox or blocks the flue entirely.
- Smoke spills into the room on startup. The damper is not opening fully, or the plate has shifted and obstructs part of the throat. This is the symptom that usually prompts the call, and it means the failure has progressed to where the fireplace is unsafe to use until repaired.
Replacement Cost & What’s Included
| Service | Price Range |
|---|---|
| Olympia Chimney throat damper replacement (standard) | $280 - $380 |
| Olympia Chimney throat damper replacement (oversized / OCM-42) | $340 - $450 |
| Frame repair or re-mortar (if needed) | $120 - $180 additional |
| Level-2 camera inspection with photo report | Included |
The range depends on three things: whether we can access the damper from the firebox or need to drop the smoke chamber, whether the frame itself needs re-mortaring into the throat, and whether your model requires the pre- or post-2008 pin size we need to match. Our estimate is the number on the invoice. We do not charge diagnostic fees separately when you proceed with the repair, and every damper replacement carries our 90-Day Done Right Promise in writing, no arguing.
DIY or Call Us?
An owner can safely check whether the handle turns freely and whether the plate moves with it, using a flashlight and a fireplace poker to nudge the plate gently. Do not force it, a seized linkage can snap and drop the plate.
Where DIY goes wrong: the damper plate sits at the top of the firebox throat, often in a space too narrow for shoulders and too dark for accurate work. The pivot pins are under spring tension, and a slipped tool can send a cast iron plate down the flue or onto the firebrick below. More critically, a damper that does not seat squarely creates a gap that you cannot see from below, you will think the repair succeeded until the first cold snap brings the draft and the heating bill. We bring the right light, the right reach tools, and the camera to verify the seal before we leave. The flue doesn’t lie, and neither do we.
Call (571) 701-8135 for a free estimate. We answer live, 24 hours a day.
FAQs
A properly installed Olympia Chimney throat damper typically lasts 15 to 20 years in Northern Virginia’s climate, though we have seen them fail in 10 when the chimney cap was missing and rainwater accelerated rust. Ashburn’s freeze-thaw cycles and summer humidity both stress the steel linkage more than drier western climates. Call (571) 701-8135 if yours is past 12 years and showing any stiffness.
Sometimes. A sheared cotter pin or detached handle linkage can be re-pinned or re-welded if the plate and frame are sound. We will not know until we inspect, and we will show you the camera footage so you can see what we see. If the plate is warped or the frame is cracked, replacement is the only sound fix. Estimates are free.
Most Olympia Chimney damper replacements take 90 minutes to two hours from ladder set to final camera check. If the smoke chamber needs to be dropped for access, add an hour. Our technicians carry the common parts and aim to complete the job in a single visit.
We stock the OCM-24, OCM-30, and OCM-36 plates and linkages, plus both pre- and post-2008 pivot hardware. The OCM-42 and some discontinued series we source overnight from our distributor. We will tell you before we book whether your part is on the truck or needs ordering.
Written by Russell Haines, Owner & Master Sweep, Hearthstone Chimney Co. at Hearthstone Chimney Co., serving Ashburn and nearby areas.





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