Test for carbon monoxide in Alexandria at least once a year before winter, and immediately if you notice symptoms like headaches or nausea near fireplaces or furnaces. Safe levels are below 9 parts per million (ppm) for 8 hours or 35 ppm for 1 hour. Edgar’s Chimney Co. includes CO testing in every inspection, our technicians use calibrated detectors and follow NFPA 211 standards to ensure your chimney isn’t leaking deadly gas into your home.
A carbon monoxide (CO) test measures how much poison gas your chimney or heating system is leaking into your home.
Carbon monoxide is odorless, colorless, and deadly, yet it’s often overlooked in Alexandria’s older homes with brick fireplaces or wood stoves. A CO test uses a calibrated detector to measure parts per million (ppm) of gas in the air near your chimney, furnace, or water heater. The Chimney Safety Institute of America (CSIA) recommends testing annually, especially before winter when heating systems run longer. In Alexandria, where humidity and older masonry can trap moisture and debris, even a small crack in your chimney lining can let CO seep into living spaces. Edgar’s Chimney Co. includes CO testing in every inspection, using professional-grade detectors that meet NFPA 211 standards. We’ll show you the numbers and explain what they mean for your safety. Full details in our service list.
Alexandria’s climate and housing make CO testing critical, here’s why.
Alexandria’s mix of historic brick homes, row houses, and modern condos near the Potomac creates unique risks. Older masonry can develop hairline cracks over time, while newer homes with sealed combustion systems may still have CO leaks if vents are blocked by creosote or animal nests. The EPA notes that improperly vented fireplaces or blocked chimneys are leading causes of CO buildup the U.S. Environmental Protection Agency. In Alexandria’s damp seasons, moisture can weaken mortar joints, increasing the chance of leaks. Edgar’s Chimney Co. sees cases where homeowners near King Street or along the waterfront report CO alarms going off after heavy rains, often because water damaged the chimney lining. That’s why we pair every CO test with a thorough inspection of your chimney’s structure, not just the flue. If your detector reads above 9 ppm over 8 hours or 35 ppm over 1 hour, we’ll pinpoint the source and recommend repairs before it becomes dangerous. Worth a look: contact the office.
What the numbers on your CO detector actually mean, and when to act.
CO levels are measured in parts per million (ppm). Here’s what the numbers mean for your Alexandria home: - Below 9 ppm (8-hour average): Safe for most people. This is the EPA’s recommended long-term exposure limit. - 9–35 ppm (8-hour average): Mild symptoms like headaches or fatigue may occur, especially in children or elderly residents. If your detector consistently reads here, schedule a chimney inspection. - 35–100 ppm (8-hour average): Noticeable symptoms like dizziness or nausea. Immediate action is needed, call Edgar’s Chimney Co. for an emergency inspection. - Above 100 ppm: Life-threatening. Evacuate your home, call 911, and contact us to assess and repair the source.
In Alexandria, we often see readings spike after a chimney sweep if creosote buildup was blocking proper airflow. Our white-glove sweeps remove all debris, ensuring clean, safe operation. We’ll also check for hidden issues like cracked liners or blocked caps that could cause future leaks. You can also review the background and licensing.
How often you should test for CO in Alexandria, based on your home’s age and risks.
The frequency depends on your home’s age, heating system, and local conditions. Here’s our recommended schedule for Alexandria homeowners: - Once a year (minimum): Before winter, especially if you use your fireplace or wood stove regularly. This aligns with CSIA guidelines and catches issues before cold weather traps CO indoors. - Every 6 months: If your home is over 50 years old (common in Old Town Alexandria) or has a masonry chimney. Older bricks and mortar are more prone to cracks. - Immediately after repairs: Any chimney relining, water damage fixes, or animal removal should trigger a CO test to ensure seals are intact. - After heavy rains or storms: Alexandria’s humidity and occasional flooding can weaken chimney structures. If you notice damp spots near your chimney, test right away.
Edgar’s Chimney Co. offers CO testing as part of our standard inspections, or as a standalone service for $99 in Alexandria. We’ll provide a written report with your results and next steps, no guesswork. For homes near the waterfront or in flood-prone areas like Del Ray, we recommend testing twice a year.
5 warning signs your Alexandria chimney is leaking CO, and what to do next.
Don’t wait for a detector to beep. Spot these warning signs in your home: 1. Flickering or yellow flames: A healthy fire burns blue. Yellow or orange flames mean incomplete combustion, often from a blocked or cracked flue. 2. Soot buildup on walls or ceilings: Black residue near the fireplace or even in other rooms signals CO is escaping. 3. CO detector alarms: Even if it’s not your chimney’s fault, investigate nearby sources like furnaces or water heaters. 4. Headaches or nausea after using the fireplace: CO poisoning causes flu-like symptoms without a fever. If these happen near your heating sources, test immediately. 5. Bird nests or debris blocking the chimney cap: Animals or leaves can trap CO inside your home. Edgar’s Chimney Co. removes nests humanely and checks for damage during cleanup.
If you spot any of these, call us for a CO test and inspection. We’ll identify the source, whether it’s a cracked liner, improper venting, or a failing appliance, and fix it with guaranteed workmanship. For example, last winter we found a hairline crack in the liner of a King Street townhome that had been leaking CO for months. The homeowner had no symptoms because the crack was small, but our detector caught it during a routine sweep.
Why Edgar’s Chimney Co. includes CO testing in every inspection, and how it saves you money.
Most chimney sweeps in Alexandria won’t test for CO unless you ask. We include it because we’ve seen firsthand how small issues turn into emergencies. Here’s how our approach protects you: - Early detection: Catching CO leaks early prevents costly repairs down the line, like relining a chimney or replacing a furnace. - Peace of mind: After your sweep, you’ll get a CO reading and a clear explanation of what it means, no confusing jargon. - Comprehensive safety: We check for CO and creosote, blockages, and structural issues in one visit. Our white-glove sweeps leave your chimney spotless and safe. - Deep local knowledge: We understand Alexandria’s homes and chimneys better than anyone. From the brick row houses near the waterfront to the modern condos in Potomac Yard, we tailor our inspections to your home’s risks.
For example, in a recent job in Oxon Hill, we found a CO leak from a blocked chimney cap, and discovered the homeowner had been using a cheap, non-certified sweep who never checked for gas. The repair cost was minimal, but the risk was high. Our inspections start at $149 in Alexandria and include CO testing, a written report, and a 30-day warranty on our work. Schedule your CO safety check today, it’s the smartest way to protect your family.
Your CO detector just sounded, here’s exactly what to do next in Alexandria.
If your detector alarms, follow these steps to stay safe: 1. Evacuate immediately: Leave your home and go to a neighbor’s or a fresh-air area. Do not re-enter until the source is identified as safe. 2. Call 911: If anyone is experiencing symptoms like confusion, vomiting, or chest pain, seek emergency medical help. 3. Do not re-light fires or use gas appliances: This can worsen the problem. 4. Call Edgar’s Chimney Co.: We’ll respond within 24 hours for an emergency inspection. Our technicians bring portable CO detectors to pinpoint the source. 5. Check nearby sources: CO can come from furnaces, water heaters, or even car exhaust near open windows. We’ll inspect all potential leaks.
Last fall, we responded to a CO alarm in a Springfield home where the homeowner thought the issue was their gas stove. Our team found a cracked chimney liner from years of undetected moisture damage. The fix was a reline, but the homeowner avoided a far worse scenario. If your detector alarms, don’t panic, but do act fast. Contact us for emergency CO testing, we’re available 24/7 for critical situations.
| Home Type | Testing Frequency | Why It Matters | Edgar’s Chimney Co. Service |
|---|---|---|---|
| Older brick homes (pre-1980) | Twice a year (spring & fall) | Aging mortar and masonry are prone to cracks that let CO seep in. | Full inspection + CO test: $199 |
| Modern homes with fireplaces | Once a year (before winter) | Sealed combustion systems can still fail if vents are blocked. | CO test only: $99 |
| Condos or apartments with gas heating | Once a year (or after repairs) | Shared vents or nearby older infrastructure can introduce risks. | Quick CO check: $79 |
| Homes near waterfront or flood zones | Every 6 months | Moisture weakens chimney structures faster. | Emergency CO + inspection: $149 (24-hour response) |
Frequently Asked Questions
My CO detector keeps going off near the fireplace, but I don’t smell gas. Is this normal?
No, it’s not normal. Even if you don’t smell anything, CO is dangerous. The issue is likely a cracked chimney liner, blocked flue, or improper venting. Edgar’s Chimney Co. sees this often in Alexandria’s older homes, especially after heavy rains weaken mortar. We’ll inspect your chimney, test for leaks, and recommend repairs before it becomes a health risk. Never ignore a detector alarm, even if it’s ‘just’ near the fireplace.
I live in a newer condo in Potomac Yard. Do I still need CO testing if I don’t have a fireplace?
Yes. Even modern homes with sealed combustion systems can develop CO leaks from furnaces, water heaters, or blocked vents. Alexandria’s humidity and older infrastructure nearby can also affect newer buildings. The EPA recommends testing near all heating sources, not just fireplaces. Edgar’s Chimney Co. offers quick CO checks for condos and apartments, it’s a smart precaution, especially if you’ve noticed drafts or strange smells near vents.
My chimney was swept last year, but my CO detector just went off. What could have changed?
Several things can cause a sudden CO leak after a sweep: new cracks from shifting bricks, a blocked chimney cap from debris or animal nests, or even a change in your wood-burning habits (like using wetter wood). In Alexandria, heavy rains or tree roots near your home can also stress chimney structures. Edgar’s Chimney Co. will re-inspect your chimney, check for hidden blockages, and test for leaks. We’ve seen cases where a perfectly fine chimney developed a leak after a neighbor’s tree fell and damaged the masonry.
How much does a CO test cost in Alexandria, and is it worth it?
A standalone CO test with Edgar’s Chimney Co. costs $99 in Alexandria. It’s worth it if you use your fireplace, have an older home, or live near waterfront areas where moisture can damage chimneys. Many homeowners skip testing until they have symptoms, but by then, the damage (or worse) may already be done. We recommend pairing CO tests with annual chimney inspections, especially before winter. For $149, you get a full inspection, CO testing, and a written report with clear next steps.