Carbon monoxide kills around 40 people in the UK every year and hospitalises around 4,000. The cause is almost always a poorly maintained fuel-burning appliance. We test combustion, inspect flues, and fit certified CO alarms — independent of any boiler sale.
Combustion analyser-tested · Independent (not tied to any install) · CO alarms to BS EN 50291 supplied & fitted
Yes
Local to Coventry CV2
Before any work
Written quotes
7 days/week
Open 24/7
Always
Customer service first
Combustion analysis on every gas appliance (boiler, fire, cooker), flue spillage testing (kit and smoke pellet), CO alarm presence and function check, ventilation adequacy assessment, room-sealed appliance integrity check (where applicable), and certified CO alarm supply and installation where missing or expired. Written report with combustion readings on every appliance tested.
Homeowners with older boilers (over 10 years) where CO risk creeps up with age. Landlords meeting their Smoke & Carbon Monoxide Alarm (England) Regulations 2022 obligations. Families with babies, young children, or elderly relatives in the home — the most vulnerable to CO. Anyone moving into a property and wanting independent verification before they trust the existing heating.
Annually on every gas appliance — alongside or as part of the annual boiler service. Immediately if a CO alarm has activated (even briefly). Immediately if anyone in the household has had repeated headaches, dizziness, nausea or unexplained tiredness in the home but not when away. Immediately after any work on the gas system that wasn't done by a Gas Safe engineer.
Most CO checks are done by the same engineer servicing the boiler — fine if they're honest, but it removes the second opinion that can save lives. An independent CO check, separate from any sale or service, gives a clean verdict from someone with no skin in the boiler-replacement game.
Carbon monoxide is the deadliest hazard in any home with a fuel-burning appliance — and the one homeowners think about least.
High CO concentrations cause unconsciousness inside 10–15 minutes and death inside 30. Survivors of acute episodes often have permanent neurological damage.
Sub-acute exposure (under 30 ppm sustained) causes headaches, tiredness, irritability, cognitive issues and depression — routinely misdiagnosed for years as anxiety, IBS or chronic fatigue.
Smaller body mass and faster respiratory rate means children absorb CO faster. Elderly with existing cardiovascular conditions are at higher risk of cardiac event from CO.
Pets often show symptoms (lethargy, vomiting, balance issues) before humans. If a pet has been unwell in a way that resolves when the boiler's off — investigate CO immediately.
Boiler case, flue route, flue terminal, ventilation provisions, gas cooker, gas fire, any solid-fuel appliances. Look for soot staining, scorching, condensate ingress.
Calibrated combustion analyser (Kane 458s) on every appliance flue. CO ppm reading, CO2 percentage, ratio (CO/CO2), and oxygen content all logged. Pass/fail clearly stated on report.
Smoke pellet test for non-room-sealed appliances, flue terminal inspection for room-sealed. Confirms combustion products go up the flue, not into the room.
Existing alarms tested with calibrated source. Expiry date checked (typical sensor life 7–10 years). Replacement or new install with BS EN 50291-certified alarms (Kidde, FireAngel) where missing or expired.
Full report with all combustion readings, alarm locations, and clear recommendations. If anything fails, what fails it and what to do — separately quoted, no upsell pressure.
Not tied to a boiler sale. If your boiler is safe, we'll tell you. If it isn't, we'll tell you why with the combustion data.
Every appliance's combustion ratio recorded — useful for resale, insurance and ongoing reference.
BS EN 50291-certified alarms (Kidde, FireAngel) with 7–10 year sensor life, supplied and fitted in the right locations.
Meets Smoke and Carbon Monoxide Alarm (England) Regulations 2022 — applicable to all let properties.
The single best night's sleep is the one after a clean CO check on a properly serviced boiler.
Routine CO checks are inexpensive. The alternative — even a single ambulance call-out — is anything but.
Carbon monoxide is produced any time a fuel doesn't burn completely. Knowing why combustion is incomplete is the entire point of a proper check — not just whether the alarm beeps.
Discuss your projectGas boilers (most common — particularly older non-condensing models or poorly maintained condensing ones). Gas fires (decorative live-fuel-effect particularly). Gas cookers (mostly during long simmering or grill use). Solid-fuel stoves and open fires. Oil-fired AGAs and Rayburns. LPG appliances on properties off-grid. Even barbecue grills used inside garages.
Good combustion gives CO under 100 ppm at the appliance flue with a CO/CO2 ratio under 0.004. Marginal is 100–400 ppm or ratio 0.004–0.008. Failure is over 400 ppm or ratio over 0.008. We measure and document every appliance against these thresholds.
Within 1–3 metres of each fuel-burning appliance. In every room where occupants sleep. At head height (CO has roughly the same density as air, so doesn't pool low or high). NOT in bathrooms or kitchens (false alarm triggers from cooking steam). Mains or sealed-battery long-life types only — never user-replaceable AA-battery alarms in let properties.
Open-flue appliances inspected for downdraft, terminal damage, bird nest blockage. Room-sealed appliances inspected for case integrity, flue collar seal, terminal external clearance to opening windows. Condensate traps inspected — a blocked condensate trap is one of the most common silent CO risks on modern condensing boilers.
Domestic CO check covers every fuel-burning appliance per visit. HMO and let property CO compliance is governed by the Smoke & Carbon Monoxide Alarm (England) Regulations 2022 — every room with a fixed combustion appliance must have a CO alarm, every storey of the property must have a smoke alarm. Commercial CO testing on larger plant requires CCN1 + COMCAT qualifications and additional regulatory reporting.
Open all windows and doors immediately. Turn off any fuel-burning appliance you can safely reach. Get everyone out of the property — including pets. Don't re-enter until a Gas Safe engineer (or emergency service) has confirmed it's safe. Call the National Gas Emergency line on 0800 111 999. Get medical attention — symptoms can develop hours after the initial exposure.
Coventry, CV2 & the wider West Midlands.
Still unsure? Call 07385 732137 — no obligation.
Call us or request a written quote — we'll come back to you fast.
Local plumber · Coventry CV2 · Open 24/7
