{"product_id":"wisualarm-carbon-monoxide-alarm-10-year-sealed-battery-lcd-display","title":"Wisualarm Carbon Monoxide Alarm | 10-Year Sealed Battery | LCD Display","description":"\u003c!--\n  SUGGESTED PRODUCT TITLE (SEO):\n  Wisualarm DHI-HY-GC20D Carbon Monoxide Alarm | 10-Year Sealed Battery | LCD Display | EN 50291-1:2018 | TÜV \u0026 CE Certified\n  MPN: DHI-HY-GC20D\n  Brand: Wisualarm (by Dahua)\n  Category: Fire \u0026 Safety \u003e Carbon Monoxide Alarms \u003e Standalone CO Alarms\n  Note: This is the STANDALONE (non-wireless) variant. For the wireless interconnected version compatible with the Wisulink RF mesh system, see DHI-HY-GC20D-R8.\n  UK Importer: Dahua Technology UK Ltd., 3rd Floor, Quantum House, 60 Norden Road, Maidenhead, SL6 4AY\n--\u003e\n\u003cstyle\u003e\n  .wu-desc * { box-sizing: border-box; }\n  .wu-desc { font-family: inherit; color: inherit; line-height: 1.7; font-size: 16px; }\n  .wu-desc p, .wu-desc li, .wu-desc td, .wu-desc th { font-size: 16px !important; line-height: 1.7; }\n  .wu-desc h2 { font-size: 22px !important; font-weight: 700; color: #1a1a2e; border-bottom: 2px solid #c0392b; padding-bottom: 6px; margin: 2rem 0 1rem; line-height: 1.3; }\n  .wu-desc h3 { font-size: 17px !important; font-weight: 700; color: #1a1a2e; margin: 1.2rem 0 0.4rem; line-height: 1.4; }\n  .wu-desc p { margin: 0 0 1rem; }\n  .wu-desc ul { padding-left: 1.5rem; margin: 0 0 1rem; }\n  .wu-desc ul li { margin-bottom: 0.5rem; }\n\n  .wu-intro-box { background: #fef5f5; border-left: 4px solid #c0392b; padding: 1.1rem 1.4rem; 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gap: 0.85rem; margin-bottom: 1.2rem; }\n  .wu-card { background: #fef5f5; border: 1px solid #f5c0c0; border-radius: 6px; padding: 1rem 1.1rem; line-height: 1.6; }\n  .wu-card strong { display: block; color: #1a1a2e; margin-bottom: 0.35rem; font-size: 16px !important; }\n\n  .wu-reg-box { background: #fff8e6; border: 1px solid #f0d080; border-radius: 6px; padding: 1rem 1.3rem; margin: 1.2rem 0; color: #5a4a00; }\n  .wu-reg-box p { margin: 0 0 0.5rem !important; }\n  .wu-reg-box p:last-child { margin: 0 !important; }\n\n  .wu-safety-box { background: #fef5f5; border: 2px solid #c0392b; border-radius: 6px; padding: 1rem 1.3rem; margin: 1.2rem 0; }\n  .wu-safety-box p { margin: 0 !important; color: #7a1a1a; }\n\n  .wu-variant-table { width: 100%; border-collapse: collapse; margin-bottom: 1.2rem; }\n  .wu-variant-table th { background: #1a1a2e; color: #fff !important; padding: 0.65rem 0.9rem; font-size: 14px !important; text-align: left; }\n  .wu-variant-table td { padding: 0.55rem 0.9rem; border-bottom: 1px solid #e8d8d8; font-size: 14px !important; vertical-align: top; }\n  .wu-variant-table tr:nth-child(even) td { background: #fef5f5; }\n  .wu-variant-table td:first-child { font-weight: 600; color: #111; width: 25%; }\n  .wu-variant-table .col-highlight td:first-child { color: #c0392b !important; font-weight: 700; }\n\n  .wu-spec-table { width: 100%; border-collapse: collapse; margin-bottom: 1.5rem; }\n  .wu-spec-table th { background: #1a1a2e; color: #fff !important; text-align: left; padding: 0.7rem 1rem; font-weight: 700; font-size: 16px !important; }\n  .wu-spec-table td { padding: 0.6rem 1rem; border-bottom: 1px solid #e8d8d8; vertical-align: top; font-size: 16px !important; }\n  .wu-spec-table tr:nth-child(even) td { background: #fef5f5; }\n  .wu-spec-table td:first-child { font-weight: 600; color: #111; width: 44%; }\n  .wu-spec-table .section-head td { background: #c0392b !important; color: #fff !important; font-weight: 700 !important; font-size: 14px !important; text-transform: uppercase; letter-spacing: 0.05em; }\n\n  .wu-install-steps { counter-reset: install-step; list-style: none !important; padding: 0 !important; margin: 0 0 1rem !important; }\n  .wu-install-steps li { counter-increment: install-step; padding: 0.6rem 0.8rem 0.6rem 3rem !important; position: relative; border-bottom: 1px solid #e8d8d8; font-size: 15px !important; margin: 0 !important; }\n  .wu-install-steps li::before { content: counter(install-step); position: absolute; left: 0.7rem; top: 50%; transform: translateY(-50%); background: #c0392b; color: #fff; width: 22px; height: 22px; border-radius: 50%; font-size: 13px !important; font-weight: 700; display: flex; align-items: center; justify-content: center; line-height: 1; }\n  .wu-install-steps li:last-child { border-bottom: none; }\n\n  .wu-faq-item { border-bottom: 1px solid #e8d8d8; padding: 1rem 0; }\n  .wu-faq-item:last-child { border-bottom: none; }\n  .wu-faq-item p { margin: 0.4rem 0 0 !important; }\n\n  .wu-infobox { background: #fef5f5; border: 1px solid #f5c0c0; border-radius: 6px; padding: 1rem 1.2rem; margin-top: 1.5rem; font-size: 16px !important; line-height: 1.6; }\n\n  @media (max-width: 600px) {\n    .wu-grid { grid-template-columns: 1fr 1fr; }\n    .wu-stat-bar { justify-content: center; }\n  }\n\u003c\/style\u003e\n\u003cdiv class=\"wu-desc\"\u003e\n\u003cdiv class=\"wu-intro-box\"\u003e\n\u003cp\u003e\u003cspan class=\"wu-badge\"\u003eStandalone\u003c\/span\u003e \u003cspan class=\"wu-badge dark\"\u003e10-Year Sealed Battery\u003c\/span\u003e\u003c\/p\u003e\n\u003cp style=\"margin-top: 0.75rem !important;\"\u003eThe \u003cstrong\u003eWisualarm \u003c\/strong\u003eDHI-HY-GC20D is a standalone carbon monoxide alarm with a \u003cstrong\u003e10-year sealed 3V CR123A lithium battery\u003c\/strong\u003e — designed to provide a full decade of continuous protection with zero battery maintenance. It uses a high-performance \u003cstrong\u003eFigaro electrochemical CO sensor\u003c\/strong\u003e, recognised as one of the most reliable and accurate sensor technologies for domestic CO detection, and is certified to \u003cstrong\u003eEN 50291-1:2018\u003c\/strong\u003e — the current British and European standard for residential CO alarms. An integrated LCD display shows live CO concentration in ppm, combined with a \u0026gt;85dB audible alarm and visual LED indicator, gives occupants clear real-time information when it matters most. A single-button test and silence function makes routine testing and false-alarm management simple.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"wu-stat-bar\"\u003e\n\u003cdiv class=\"wu-stat\"\u003e\n\u003cdiv class=\"num\"\u003e10yr\u003c\/div\u003e\n\u003cdiv class=\"lbl\"\u003eSealed Battery Life\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"wu-stat\"\u003e\n\u003cdiv class=\"num\"\u003e85dB+\u003c\/div\u003e\n\u003cdiv class=\"lbl\"\u003eAlarm Volume @ 3m\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"wu-stat\"\u003e\n\u003cdiv class=\"num\"\u003eLCD\u003c\/div\u003e\n\u003cdiv class=\"lbl\"\u003eLive CO Display (ppm)\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"wu-stat\"\u003e\n\u003cdiv class=\"num\"\u003e~45s\u003c\/div\u003e\n\u003cdiv class=\"lbl\"\u003eSilence Duration\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"wu-stat\"\u003e\n\u003cdiv class=\"num\"\u003eEN 50291\u003c\/div\u003e\n\u003cdiv class=\"lbl\"\u003e-1:2018 Certified\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"wu-stat\"\u003e\n\u003cdiv class=\"num\"\u003e125g\u003c\/div\u003e\n\u003cdiv class=\"lbl\"\u003eWeight\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"wu-reg-box\"\u003e\n\u003cp\u003e🏠 \u003cstrong\u003eUK Legal Requirement — Smoke and Carbon Monoxide Alarm (Amendment) Regulations 2022:\u003c\/strong\u003e Since 1 October 2022, private sector landlords in England are legally required to install a CO alarm in any room with a fixed combustion appliance (excluding gas cookers). This includes rooms with gas boilers, gas fires, oil boilers, solid fuel stoves and open fireplaces. Social landlords have been subject to the same requirement since 1 February 2023. The DHI-HY-GC20D, certified to EN 50291-1:2018, meets the technical standard required to comply with this legislation. Similar requirements apply in Scotland, Wales and Northern Ireland under their respective regulations.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003ch2\u003eKey Features\u003c\/h2\u003e\n\u003cdiv class=\"wu-grid\"\u003e\n\u003cdiv class=\"wu-card\"\u003e\n\u003cstrong\u003e🔬 Figaro Electrochemical CO Sensor\u003c\/strong\u003eThe Figaro electrochemical sensor is a precision CO detection technology that measures CO concentration through a controlled electrochemical reaction. It delivers high sensitivity, excellent selectivity (low cross-sensitivity to hydrogen and other gases that trigger false alarms in cheaper catalyst-bead sensors), fast response to rising CO levels, and a stable, calibrated performance maintained over the full 10-year sensor life.\u003c\/div\u003e\n\u003cdiv class=\"wu-card\"\u003e\n\u003cstrong\u003e📺 LCD Display — Live CO Reading in ppm\u003c\/strong\u003eThe integrated LCD screen shows the current carbon monoxide concentration in parts per million (ppm) in real time. This is particularly valuable to emergency responders and service engineers: rather than just knowing the alarm has triggered, they can see the actual concentration level — helping to determine the severity of a leak and whether evacuation or ventilation is sufficient. The display also shows a peak-level CO memory, recording the highest concentration detected.\u003c\/div\u003e\n\u003cdiv class=\"wu-card\"\u003e\n\u003cstrong\u003e🔋 10-Year Sealed Battery — Zero Maintenance\u003c\/strong\u003eA non-replaceable 3V CR123A lithium battery powers the alarm for its entire 10-year service life. The sealed design eliminates the most common cause of CO alarm failure: occupants removing or not replacing flat batteries. At end of life, the unit emits an end-of-life warning and the entire alarm is replaced — ensuring the sensor and battery are always within their service window. Ideal for rental properties where battery maintenance cannot be guaranteed.\u003c\/div\u003e\n\u003cdiv class=\"wu-card\"\u003e\n\u003cstrong\u003e🔊 \u0026gt;85dB Audible + Visual Alarm\u003c\/strong\u003eThe alarm sounder exceeds 85dB(A) measured at 3 metres, meeting the EN 50291 audible output requirement. A visual LED indicator provides an additional alarm signal — important for occupants with hearing impairment and for confirming alarm status from a distance. The combined audio\/visual indication continues until the alarm is silenced or the CO level drops below the threshold.\u003c\/div\u003e\n\u003cdiv class=\"wu-card\"\u003e\n\u003cstrong\u003e🔕 Test and Silence — Single Button\u003c\/strong\u003eOne button handles both routine self-testing (press to trigger the test cycle, confirming sensor, sounder and battery are functional) and temporary silencing during a nuisance alarm event — typically caused by brief peaks from cooking near the unit. The ~45-second silence duration prevents extended disturbance while keeping the alarm active to detect genuine CO build-up. Silencing does not disable the alarm permanently.\u003c\/div\u003e\n\u003cdiv class=\"wu-card\"\u003e\n\u003cstrong\u003e📍 Standalone — No Wiring, No Hub Required\u003c\/strong\u003eThe DHI-HY-GC20D operates entirely independently — no mains wiring, no Wi-Fi, no gateway, no subscription, no app. It is ready to use straight from the box with a simple wall-mount installation. This makes it the right choice wherever a simple, reliable, code-compliant CO alarm is needed without any infrastructure requirements. For wireless interconnected coverage across a whole property, see the DHI-HY-GC20D-R8 variant.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003ch2\u003eWhere to Install\u003c\/h2\u003e\n\u003cp\u003eCO alarms should be installed wherever a combustion appliance is present and wherever occupants sleep. The following guidance is based on BS EN 50292 (the installation standard that accompanies EN 50291) and HSE recommendations:\u003c\/p\u003e\n\u003cul class=\"wu-install-steps\"\u003e\n\u003cli\u003e\n\u003cstrong\u003eEvery room with a fixed combustion appliance\u003c\/strong\u003e — gas or oil boiler, gas fire, wood-burning stove, open fireplace, log burner, or pellet stove. The alarm should be on the same level as the appliance, within 1–3 metres where possible.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEach sleeping level of the home\u003c\/strong\u003e — CO is particularly dangerous at night when occupants cannot self-evacuate. An alarm in or adjacent to sleeping areas provides the earliest possible warning.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMounting height\u003c\/strong\u003e — CO has a similar density to air and disperses evenly. EN 50292 recommends mounting on a wall or ceiling. Wall mounting: between 1.5m and 2.1m above the floor. Ceiling mounting: as per manufacturer instructions (minimum 300mm from walls\/corners).\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAvoid\u003c\/strong\u003e — direct sunlight, areas of high humidity (bathrooms, directly above cookers), areas with strong airflow (directly next to windows, fans or air conditioning vents), and garages or enclosed parking areas (vehicle exhaust will trigger the alarm).\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eStandalone vs Wireless Interconnected — Which Variant?\u003c\/h2\u003e\n\u003ctable class=\"wu-variant-table\"\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003eFeature\u003c\/th\u003e\n\u003cth\u003eDHI-HY-GC20D ★ (this product)\u003cbr\u003e\u003csmall\u003eStandalone\u003c\/small\u003e\n\u003c\/th\u003e\n\u003cth\u003eDHI-HY-GC20D-R8\u003cbr\u003e\u003csmall\u003eWireless Interconnected\u003c\/small\u003e\n\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eWireless interconnection\u003c\/td\u003e\n\u003ctd\u003e✗ No\u003c\/td\u003e\n\u003ctd\u003e✓ Yes — up to 24 Wisulink devices\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eApp \/ smart home integration\u003c\/td\u003e\n\u003ctd\u003e✗ No\u003c\/td\u003e\n\u003ctd\u003e✓ Optional — via DHI-HY-GW01A Gateway\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBattery\u003c\/td\u003e\n\u003ctd\u003e10-year sealed CR123A (non-replaceable)\u003c\/td\u003e\n\u003ctd\u003e10-year sealed CR123A (non-replaceable)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLCD CO display\u003c\/td\u003e\n\u003ctd\u003e✓ Yes\u003c\/td\u003e\n\u003ctd\u003e✓ Yes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAlarm volume\u003c\/td\u003e\n\u003ctd\u003e\u0026gt;85dB @ 3m\u003c\/td\u003e\n\u003ctd\u003e\u0026gt;85dB @ 3m\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eEN 50291-1:2018 certified\u003c\/td\u003e\n\u003ctd\u003e✓ Yes\u003c\/td\u003e\n\u003ctd\u003e✓ Yes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOperating temperature\u003c\/td\u003e\n\u003ctd\u003e-10°C to +40°C\u003c\/td\u003e\n\u003ctd\u003e-10°C to +55°C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBest for\u003c\/td\u003e\n\u003ctd\u003eSingle-room compliance, simple installs, rental properties, cost-effective standalone protection\u003c\/td\u003e\n\u003ctd\u003eMulti-room or whole-home coverage, properties where alarm in one room should sound all alarms, smart monitoring via app\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cdiv class=\"wu-safety-box\"\u003e\n\u003cp\u003e⚠️ \u003cstrong\u003eCarbon monoxide — know the symptoms:\u003c\/strong\u003e CO is colourless and odourless — it cannot be detected by the senses alone. Symptoms of CO poisoning include headache, dizziness, nausea, breathlessness and confusion. If your CO alarm sounds: \u003cstrong\u003edo not ignore it\u003c\/strong\u003e. Open windows and doors, evacuate immediately, do not re-enter until declared safe by the emergency services or gas-safe engineer. Call the Gas Emergency number: \u003cstrong\u003e0800 111 999\u003c\/strong\u003e.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003ch2\u003eTechnical Specifications\u003c\/h2\u003e\n\u003ctable class=\"wu-spec-table\"\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003eSpecification\u003c\/th\u003e\n\u003cth\u003eDetail\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr class=\"section-head\"\u003e\n\u003ctd colspan=\"2\"\u003eProduct Identity\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eModel number\u003c\/td\u003e\n\u003ctd\u003eDHI-HY-GC20D\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBrand\u003c\/td\u003e\n\u003ctd\u003eWisualarm (by Dahua)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eVariant\u003c\/td\u003e\n\u003ctd\u003eStandalone (non-wireless)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr class=\"section-head\"\u003e\n\u003ctd colspan=\"2\"\u003eDetection\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSensor type\u003c\/td\u003e\n\u003ctd\u003eElectrochemical (Figaro)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eGas detected\u003c\/td\u003e\n\u003ctd\u003eCarbon monoxide (CO)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSensor life\u003c\/td\u003e\n\u003ctd\u003e10 years\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr class=\"section-head\"\u003e\n\u003ctd colspan=\"2\"\u003eAlarm Output\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAlarm volume\u003c\/td\u003e\n\u003ctd\u003eOver 85dB(A) at 3 metres\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAlarm mode\u003c\/td\u003e\n\u003ctd\u003eVisual (LED) and audible\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSilence function\u003c\/td\u003e\n\u003ctd\u003eSupported\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSilence duration\u003c\/td\u003e\n\u003ctd\u003eApproximately 45 seconds\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDisplay\u003c\/td\u003e\n\u003ctd\u003eLCD — live CO concentration (ppm) and peak-level memory\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr class=\"section-head\"\u003e\n\u003ctd colspan=\"2\"\u003ePower\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePower source\u003c\/td\u003e\n\u003ctd\u003e3V CR123A lithium battery (non-replaceable, sealed)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBattery life\u003c\/td\u003e\n\u003ctd\u003e10 years\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLow battery warning\u003c\/td\u003e\n\u003ctd\u003eYes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eEnd-of-life warning\u003c\/td\u003e\n\u003ctd\u003eYes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr class=\"section-head\"\u003e\n\u003ctd colspan=\"2\"\u003eEnvironmental\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eUsage environment\u003c\/td\u003e\n\u003ctd\u003eIndoor use only\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOperating temperature\u003c\/td\u003e\n\u003ctd\u003e-10°C to +40°C (+14°F to +104°F)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRelative humidity\u003c\/td\u003e\n\u003ctd\u003e≤95% RH (non-condensing)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr class=\"section-head\"\u003e\n\u003ctd colspan=\"2\"\u003ePhysical\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDimensions (L × W × H)\u003c\/td\u003e\n\u003ctd\u003e116.4 × 71.7 × 28.3mm (4.58\" × 2.82\" × 1.11\")\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e125g\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eHousing material\u003c\/td\u003e\n\u003ctd\u003ePC + ABS\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eInstallation method\u003c\/td\u003e\n\u003ctd\u003eWall mount\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr class=\"section-head\"\u003e\n\u003ctd colspan=\"2\"\u003eCertifications \u0026amp; Standards\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eStandard compliance\u003c\/td\u003e\n\u003ctd\u003eEN 50291-1:2018\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCertifications\u003c\/td\u003e\n\u003ctd\u003eTÜV, CE\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWireless interconnection\u003c\/td\u003e\n\u003ctd\u003eNot supported (standalone only)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch2\u003eFAQs\u003c\/h2\u003e\n\u003cdiv class=\"wu-faq-item\"\u003e\n\u003ch3\u003eDoes this alarm comply with the Smoke and Carbon Monoxide Alarm Regulations 2022?\u003c\/h3\u003e\n\u003cp\u003eYes. The DHI-HY-GC20D is certified to EN 50291-1:2018, which is the standard specified in the statutory guidance accompanying the Smoke and Carbon Monoxide Alarm (Amendment) Regulations 2022 (England). It meets the technical requirements for a compliant CO alarm for private and social rented properties. The regulations require CO alarms in rooms with fixed combustion appliances (excluding gas cookers); this alarm is appropriate for those locations when used as a standalone unit. For properties requiring interconnected alarms across multiple rooms (e.g. to meet Scottish regulations under the Housing (Scotland) Act 2006), the wireless DHI-HY-GC20D-R8 variant should be considered.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"wu-faq-item\"\u003e\n\u003ch3\u003eCan the battery be replaced when it runs low?\u003c\/h3\u003e\n\u003cp\u003eNo — the battery is permanently sealed within the unit and is not designed to be replaced. This is a deliberate safety feature: the sealed design ensures the alarm cannot be inadvertently disabled by battery removal, and the 10-year service life is matched to the sensor's operational lifespan. When the end-of-life warning sounds (typically after 10 years), the entire unit should be replaced. This is consistent with BS EN 50291 guidance on CO alarm replacement intervals.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"wu-faq-item\"\u003e\n\u003ch3\u003eWhat is the difference between this and the DHI-HY-GC20D-R8?\u003c\/h3\u003e\n\u003cp\u003eThe \u003cstrong\u003eDHI-HY-GC20D\u003c\/strong\u003e (this product) is a standalone alarm — it operates independently, with no wireless connectivity to other alarms. It is the simpler, lower-cost option for single-room CO protection or for properties where interconnection is not required. The \u003cstrong\u003eDHI-HY-GC20D-R8\u003c\/strong\u003e adds Wisulink RF wireless interconnection, allowing it to communicate with up to 24 other Wisualarm devices (smoke alarms, heat alarms, CO alarms) — when one triggers, all sound simultaneously. It can also be connected to the optional Wisualarm Gateway (DHI-HY-GW01A) for smartphone app alerts. Both share the same Figaro electrochemical sensor, LCD display and 10-year sealed battery.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"wu-faq-item\"\u003e\n\u003ch3\u003eMy alarm is beeping briefly every minute — is this an emergency?\u003c\/h3\u003e\n\u003cp\u003eA single brief beep every 30–60 seconds typically indicates either a low battery warning or an end-of-life signal — not a CO alarm event. A CO alarm triggers a continuous or rapid pattern of beeps. Refer to the user manual for the specific beep pattern meanings for this model. If the rapid alarm pattern sounds, treat it as a CO emergency, evacuate, and call the gas emergency line (0800 111 999) — do not assume it is a false alarm without investigation by a qualified engineer.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e","brand":"Wisualarm","offers":[{"title":"Default Title","offer_id":63582067130717,"sku":"DHI-HY-GC20D","price":17.95,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0958\/2051\/3629\/files\/WisuAlarmCOMonoxideAlarmDHI-HY-GC20D.png?v=1771922374","url":"https:\/\/qualityheating.co.uk\/products\/wisualarm-carbon-monoxide-alarm-10-year-sealed-battery-lcd-display","provider":"AIZO Quality Heating","version":"1.0","type":"link"}