{"product_id":"oso-super-xpress-s2x-300l-direct-unvented-hot-water-cylinder-pre-plumbed-electric","title":"OSO Super Xpress S2X 300L Direct Unvented Hot Water Cylinder | Pre-Plumbed Electric","description":"\u003cstyle\u003e\n ── Reset ── ,\n.qh-pd, .qh-pd *::before, .qh-pd *::after { box-sizing: border-box; margin: 0; padding: 0; }\n.qh-pd { font-family: inherit; font-size: 16px; line-height: 1.65; color: #1a1a1a; }\n\n ── Brand tokens ── ,\n Primary #008377 | Dark #005f55 | Light bg #e6f4f3 | Amber #f4a921 | Warn-orange #e65100 | Info-blue #1565c0 ,\n\n ── Badges ── ,\n.qh-pd .badge-row { display: flex; flex-wrap: wrap; gap: 6px; margin-bottom: 1.25rem; }\n.qh-pd .badge { display: inline-block; font-size: 11px; font-weight: 700; border-radius: 4px;\n  padding: 3px 10px; letter-spacing: 0.05em; text-transform: uppercase; }\n.qh-pd .b-teal   { background: #008377; color: #fff; }\n.qh-pd .b-dark   { background: #005f55; color: #fff; }\n.qh-pd .b-amber  { background: #f4a921; color: #1a1a1a; 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margin-bottom: 1.5rem; }\n.qh-pd .spec-table { width: 100%; border-collapse: collapse; font-size: 13.5px; min-width: 520px; }\n.qh-pd .spec-table th, .qh-pd .spec-table td { padding: 7px 11px; border-bottom: 1px solid #d4eeeb; vertical-align: top; word-break: break-word; }\n.qh-pd .spec-table thead th { background: #005f55; color: #fff; font-weight: 700; text-align: left; white-space: nowrap; }\n.qh-pd .spec-table thead th:first-child { min-width: 200px; }\n.qh-pd .spec-table tbody tr:nth-child(even) td { background: #e6f4f3; }\n.qh-pd .spec-table tbody tr:nth-child(odd)  td { background: #fff; }\n.qh-pd .spec-table tbody td:first-child { font-weight: 600; color: #005f55; }\n.qh-pd .sku { font-family: 'Courier New', monospace; font-size: 12px; background: #e6f4f3;\n  color: #005f55; padding: 2px 6px; border-radius: 3px; font-weight: 700; }\n\n ── Callouts ── ,\n.qh-pd .callout { padding: 0.85rem 1.15rem; border-radius: 0 6px 6px 0; margin: 0.9rem 0;\n  font-size: 14.5px; line-height: 1.7; }\n.qh-pd .callout-teal  { background: #e6f4f3; border-left: 4px solid #008377; color: #00443d; }\n.qh-pd .callout-amber { background: #fef8ec; border-left: 4px solid #f4a921; color: #4a3000; }\n.qh-pd .callout-warn  { background: #fff3e0; border-left: 4px solid #e65100; color: #4a1800; }\n.qh-pd .callout-blue  { background: #e8f4fd; border-left: 4px solid #1565c0; color: #0a2a50; }\n\n ── Steps (flexbox — Shopify safe) ── ,\n.qh-pd .steps { list-style: none; padding: 0; margin-bottom: 1.4rem; counter-reset: step; }\n.qh-pd .steps li { counter-increment: step; display: flex; align-items: flex-start; gap: 0.85rem;\n  padding: 0.75rem; border-radius: 6px; margin-bottom: 0.5rem;\n  font-size: 14.5px; line-height: 1.7; background: #fff; border: 1px solid #d4eeeb; }\n.qh-pd .steps li::before { content: counter(step);\n  display: flex; align-items: center; justify-content: center;\n  flex: 0 0 28px; width: 28px; height: 28px; min-width: 28px; border-radius: 50%;\n  background: #008377; color: #fff; font-size: 13px; font-weight: 800; line-height: 1; margin-top: 3px; }\n.qh-pd .steps li strong { color: #005f55; }\n\n ── FAQ ── ,\n.qh-pd .faq-item { border-bottom: 1px solid #d4eeeb; padding: 0.85rem 0; }\n.qh-pd .faq-item:last-child { border-bottom: none; }\n.qh-pd .faq-q { font-size: 14.5px; font-weight: 700; color: #005f55;\n  padding-left: 1.4rem; position: relative; }\n.qh-pd .faq-q::before { content: \"Q\"; position: absolute; left: 0; color: #008377; font-weight: 900; }\n.qh-pd .faq-a { font-size: 14px; color: #2a2a2a; margin-top: 0.4rem; padding-left: 1.4rem; line-height: 1.7; }\n\n ── Box grid (what's included) ── ,\n.qh-pd .box-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));\n  gap: 0.6rem; margin-bottom: 1.4rem; }\n.qh-pd .box-item { background: #e6f4f3; border: 1px solid #b2dcd8; border-radius: 6px;\n  padding: 0.6rem 0.75rem; font-size: 13.5px; color: #00443d;\n  display: flex; align-items: flex-start; gap: 0.4rem; }\n.qh-pd .box-item::before { content: \"✔\"; color: #008377; font-weight: 900; flex-shrink: 0; margin-top: 1px; }\n\n ── Dark strip ── ,\n.qh-pd .dark-strip { background: #005f55; color: #fff; border-radius: 6px;\n  padding: 0.8rem 1.1rem; font-size: 14px; margin-bottom: 1.4rem; line-height: 1.7; }\n.qh-pd .dark-strip strong { color: #7fe8df; }\n\n ── Advantage pills ── ,\n.qh-pd .adv-grid { display: flex; flex-wrap: wrap; gap: 0.5rem; margin-bottom: 1.4rem; }\n.qh-pd .adv-pill { background: #005f55; color: #fff; border-radius: 20px;\n  padding: 5px 14px; font-size: 13px; font-weight: 700; }\n\u003c\/style\u003e\n\n\u003cdiv class=\"qh-pd\"\u003e\n\u003cdiv class=\"badge-row\"\u003e\n\u003cspan class=\"badge b-teal\"\u003eDirect Unvented Cylinder\u003c\/span\u003e\u003cspan class=\"badge b-dark\"\u003eS2X 300L\u003c\/span\u003e\u003cspan class=\"badge b-amber\"\u003ePre-Plumbed \u0026amp; Pre-Wired\u003c\/span\u003e\u003cspan class=\"badge b-teal\"\u003e30% More Hot Water\u003c\/span\u003e\u003cspan class=\"badge b-grey\"\u003eTwin 3+3 kW Immersion\u003c\/span\u003e\u003cspan class=\"badge b-outline\"\u003e25-Year Cylinder Warranty\u003c\/span\u003e\u003cspan class=\"badge b-blue\"\u003eOff-Peak Tariff Ready\u003c\/span\u003e\n\u003c\/div\u003e\n\u003cp class=\"prod-desc\"\u003eThe OSO Super Xpress 2.0 (S2X) 300L is a direct electric unvented hot water cylinder that delivers up to 30% more usable hot water than comparable competitor cylinders, thanks to OSO's unique temperature stratification and cylinder geometry optimisation. Using OSO's patented S-DESIGN, all pipework, expansion vessels, and electrical cables are concealed under a lid for a clean, professional finish. The S2X 300L is insulated with 4th-generation PUR foam for excellent heat retention and low standing losses. Twin 3 kW TITANIUM IMMERSION heaters (upper and lower) provide both rapid heat-up and off-peak economy flexibility. The entire G3 Building Regulations kit — expansion vessels, inlet control valve, tundish, drain cock — is factory-fitted, saving significant installation time. The S2X is built from stainless steel using OSO's ULTRAWELD Duplex laser-welded construction and backed by a 25-year cylinder warranty.\u003c\/p\u003e\n\u003cdiv class=\"section-label\"\u003eKey Features\u003c\/div\u003e\n\u003cul class=\"feat-list\"\u003e\n\u003cli\u003eUp to 30% MORE usable hot water than competitor cylinders of the same nominal volume\u003c\/li\u003e\n\u003cli\u003eEffective hot water capacity at 40°C: 495L from a 300L cylinder\u003c\/li\u003e\n\u003cli\u003eS-DESIGN: all pipe connections exit from the rear, all concealed under lid — clean professional finish\u003c\/li\u003e\n\u003cli\u003e4th-generation PUR foam insulation for reduced standing heat loss\u003c\/li\u003e\n\u003cli\u003eTwin 3+3 kW TITANIUM IMMERSION heaters — upper element for rapid heat-up, lower for off-peak economy heating\u003c\/li\u003e\n\u003cli\u003eTARIFF-READY: twin immersion configuration supports off-peak (Economy 7 \/ Economy 10) tariffs\u003c\/li\u003e\n\u003cli\u003e75°C thermostat setpoint — maximises stratification and effective hot water availability\u003c\/li\u003e\n\u003cli\u003eFully pre-plumbed and wired — integral expansion vessels and valve set factory-fitted, saving up to 70% installation time\u003c\/li\u003e\n\u003cli\u003eIntegral G3 kit: 2 × 8L expansion vessels, strainer, PRV, expansion relief, drain cock, tundish — all factory-fitted\u003c\/li\u003e\n\u003cli\u003eMixing valve preset to 60°C — scalding protection at draw-off points\u003c\/li\u003e\n\u003cli\u003eMains pressure hot water delivery to all outlets — no need for a pump\u003c\/li\u003e\n\u003cli\u003eULTRAWELD Duplex stainless steel laser-welded construction — 25-year cylinder warranty\u003c\/li\u003e\n\u003cli\u003eNANOPUR high-grade insulation system\u003c\/li\u003e\n\u003cli\u003eShortest cylinder system on the market — enables downsizing to a smaller volume with the same hot water output\u003c\/li\u003e\n\u003cli\u003eXL tapping profile — suitable for large family homes and high-demand properties\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cdiv class=\"section-label\"\u003eOSO Technology Advantages\u003c\/div\u003e\n\u003cdiv class=\"adv-grid\"\u003e\n\u003cspan class=\"adv-pill\"\u003eS-DESIGN — All Connections Hidden\u003c\/span\u003e\u003cspan class=\"adv-pill\"\u003eNANOPUR — High-Grade Insulation\u003c\/span\u003e\u003cspan class=\"adv-pill\"\u003eULTRAWELD — Superior Corrosion Resistance\u003c\/span\u003e\u003cspan class=\"adv-pill\"\u003eTITANIUM IMMERSION — Hard Water Durability\u003c\/span\u003e\u003cspan class=\"adv-pill\"\u003eTARIFF-READY — Twin Immersions\u003c\/span\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"section-label\"\u003eWhat's Included\u003c\/div\u003e\n\u003cdiv class=\"box-grid\"\u003e\n\u003cdiv class=\"box-item\"\u003eS2X 300L direct cylinder (pre-plumbed \u0026amp; pre-wired)\u003c\/div\u003e\n\u003cdiv class=\"box-item\"\u003eTwin 3+3 kW TITANIUM IMMERSION heaters (factory-fitted)\u003c\/div\u003e\n\u003cdiv class=\"box-item\"\u003eMixing valve — preset 60°C\u003c\/div\u003e\n\u003cdiv class=\"box-item\"\u003eP\u0026amp;T safety valve (10 bar \/ 90–95°C)\u003c\/div\u003e\n\u003cdiv class=\"box-item\"\u003e2 × 8L integral expansion vessels (factory-fitted)\u003c\/div\u003e\n\u003cdiv class=\"box-item\"\u003eInlet control valve (strainer + PRV + expansion relief)\u003c\/div\u003e\n\u003cdiv class=\"box-item\"\u003eDrain cock\u003c\/div\u003e\n\u003cdiv class=\"box-item\"\u003eTundish\u003c\/div\u003e\n\u003cdiv class=\"box-item\"\u003eFitting template\u003c\/div\u003e\n\u003cdiv class=\"box-item\"\u003eInstallation manual\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"section-label\"\u003eTechnical Specifications\u003c\/div\u003e\n\u003cdiv class=\"table-scroll\"\u003e\u003ctable class=\"spec-table\"\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eSpecification\u003c\/th\u003e\n\u003cth\u003eUnit\u003c\/th\u003e\n\u003cth\u003eValue\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eProduct Number\u003c\/td\u003e\n\u003ctd\u003eOSO\u003c\/td\u003e\n\u003ctd\u003e11011690\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eProduct Name\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003ctd\u003eS2X 300\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eNominal Volume\u003c\/td\u003e\n\u003ctd\u003eL\u003c\/td\u003e\n\u003ctd\u003e280\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eEffective Capacity at 40°C\u003c\/td\u003e\n\u003ctd\u003eL\u003c\/td\u003e\n\u003ctd\u003e495\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDimensions (H × Ø)\u003c\/td\u003e\n\u003ctd\u003emm\u003c\/td\u003e\n\u003ctd\u003e1780 × 595\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight (empty)\u003c\/td\u003e\n\u003ctd\u003ekg\u003c\/td\u003e\n\u003ctd\u003e56\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight (full)\u003c\/td\u003e\n\u003ctd\u003ekg\u003c\/td\u003e\n\u003ctd\u003e336\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eThermostat Setpoint\u003c\/td\u003e\n\u003ctd\u003e°C\u003c\/td\u003e\n\u003ctd\u003e75\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eHeat Loss (EN 12897)\u003c\/td\u003e\n\u003ctd\u003eW\u003c\/td\u003e\n\u003ctd\u003e82\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eHeat Loss \/ 24 hrs\u003c\/td\u003e\n\u003ctd\u003ekWh\/day\u003c\/td\u003e\n\u003ctd\u003e1.968\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAnnual Energy Consumption\u003c\/td\u003e\n\u003ctd\u003ekWh\/year\u003c\/td\u003e\n\u003ctd\u003e4478\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eEnergy Efficiency\u003c\/td\u003e\n\u003ctd\u003e%\u003c\/td\u003e\n\u003ctd\u003e37.4\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eEnergy Rating\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003ctd\u003eD\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTapping Profile\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003ctd\u003eXL\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImmersion Power\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003ctd\u003e3+3 kW\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eElectrical Supply\u003c\/td\u003e\n\u003ctd\u003eV\u003c\/td\u003e\n\u003ctd\u003e240 V single-phase\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMax Operating Pressure\u003c\/td\u003e\n\u003ctd\u003ebar\u003c\/td\u003e\n\u003ctd\u003e6\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eExpansion Vessels\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003ctd\u003e2 × 8L factory-fitted\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMixing Valve Preset\u003c\/td\u003e\n\u003ctd\u003e°C\u003c\/td\u003e\n\u003ctd\u003e60\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eP\u0026amp;T Valve Rating\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003ctd\u003e10 bar \/ 90–95°C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCylinder Material\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003ctd\u003eStainless steel — ULTRAWELD Duplex laser-welded\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImmersion Type\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003ctd\u003eTITANIUM IMMERSION (upper + lower)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eInsulation\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003ctd\u003e4th-generation PUR foam (NANOPUR)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCylinder Warranty\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003ctd\u003e25 years\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003c\/div\u003e\n\u003cdiv class=\"callout callout-teal\"\u003eℹ️ \u003cstrong\u003eDownsize with confidence:\u003c\/strong\u003e Because the S2X 300L delivers up to 30% more usable hot water than competitor cylinders of the same nominal size, many installers can specify a smaller S2X model and achieve the same or better hot water delivery. A smaller cylinder also means lower standing heat losses, helping with SAP \/ Part L compliance.\u003c\/div\u003e\n\u003cdiv class=\"section-label\"\u003eInstallation Overview\u003c\/div\u003e\n\u003cdiv class=\"callout callout-warn\"\u003e⚠️ \u003cstrong\u003eG3-qualified installer required:\u003c\/strong\u003e Installation must be carried out by an installer holding a current G3 Unvented Hot Water Systems qualification. All electrical work must comply with BS 7671. Notify Building Control if required by local authority.\u003c\/div\u003e\n\u003col class=\"steps\"\u003e\n\u003cli\u003e\u003cdiv\u003e\n\u003cstrong\u003eCheck dimensions and floor load:\u003c\/strong\u003e Confirm the cylinder footprint (1780mm H × 595mm Ø) fits the installation space. Allow a minimum 150mm clearance at the rear for connections and 400mm above the unit. Verify the floor can support the loaded weight (336 kg).\u003c\/div\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cdiv\u003e\n\u003cstrong\u003eFix the fitting template:\u003c\/strong\u003e Tape the supplied template to the rear wall. Mark and drill the positions for the rear pipe tails. The S-DESIGN has all connections exiting from the rear — connect the pre-cut pipe tails to your distribution pipework before sliding the cylinder into place.\u003c\/div\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cdiv\u003e\n\u003cstrong\u003eCold water supply:\u003c\/strong\u003e Connect the mains cold supply to the integrated inlet control valve. Ensure mains pressure is within the 6-bar working pressure limit — fit an upstream PRV if needed. Do not use the balanced cold outlet for anything other than mixer showers (Water Regulations).\u003c\/div\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cdiv\u003e\n\u003cstrong\u003eHot water and distribution pipework:\u003c\/strong\u003e Connect the hot water outlet to your distribution pipework. The factory-set 60°C mixing valve provides scalding protection. The S2X delivers mains pressure hot water — no pump is required.\u003c\/div\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cdiv\u003e\n\u003cstrong\u003eTundish and discharge pipe:\u003c\/strong\u003e Connect the tundish discharge to a suitable indirect discharge pipe with the correct air gap, positioned in accordance with BS 6700 and Building Regulations Part G.\u003c\/div\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cdiv\u003e\n\u003cstrong\u003eElectrical connections:\u003c\/strong\u003e Connect each immersion heater element to its own dedicated 240V 13A FCU. The lower element is typically wired to an off-peak tariff supply (Economy 7 \/ Economy 10) and the upper to the standard supply for top-up heating. Follow the wiring diagram in the installation manual.\u003c\/div\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cdiv\u003e\n\u003cstrong\u003eFill, commission and test:\u003c\/strong\u003e Fill slowly with cold water. Bleed air from all hot outlets. Check for leaks. Switch on and allow to reach operating temperature. Test the mixing valve outlet temperature. Complete the G3 commissioning record.\u003c\/div\u003e\u003c\/li\u003e\n\u003c\/ol\u003e\n\u003cdiv class=\"section-label\"\u003eFrequently Asked Questions\u003c\/div\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cdiv class=\"faq-q\"\u003eHow does the S2X deliver 30% more hot water than other cylinders?\u003c\/div\u003e\n\u003cdiv class=\"faq-a\"\u003eThe S2X achieves this through a combination of precise cylinder geometry, temperature stratification at 75°C, and OSO's unique design. At 75°C, the stored water volume contains significantly more heat energy than competitors' cylinders set at 60°C. The effective usable capacity at 40°C draw-off temperature is 495L — well above the nominal 300L. This means you can often downsize, saving cost, space, and standing heat losses.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cdiv class=\"faq-q\"\u003eWhat is the difference between the upper and lower immersion heaters?\u003c\/div\u003e\n\u003cdiv class=\"faq-a\"\u003eThe S2X has twin 3 kW immersion heaters. The upper element heats only the top portion of the cylinder for quick heat recovery — useful when you've used some hot water and need a rapid top-up. The lower element heats the full cylinder volume and is typically connected to an off-peak tariff (Economy 7 or Economy 10) to heat the whole tank overnight at cheaper rates. Both work independently.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cdiv class=\"faq-q\"\u003eIs the S2X suitable for off-peak electricity tariffs?\u003c\/div\u003e\n\u003cdiv class=\"faq-a\"\u003eYes — the twin immersion design is specifically described as TARIFF-READY. The lower immersion can be wired to an off-peak supply and the upper to a standard supply. During off-peak hours, the lower element heats the full cylinder; during the day, the upper element provides top-up heating at any time. This can significantly reduce running costs.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cdiv class=\"faq-q\"\u003eCan I install an S2X 300L as a replacement for an existing vented cylinder?\u003c\/div\u003e\n\u003cdiv class=\"faq-a\"\u003eYes, but you'll need to ensure your water supply is mains-fed (i.e. adequate mains pressure) and that there is no gravity-fed storage tank supplying the current system. A G3-qualified installer must carry out the installation, and Building Control notification may be required. The S-DESIGN rear-connection system also means the cylinder must have rear wall clearance of at least 150mm.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cdiv class=\"faq-q\"\u003eWhat warranty does the S2X carry?\u003c\/div\u003e\n\u003cdiv class=\"faq-a\"\u003eThe stainless steel cylinder carries a 25-year warranty against defects in materials and manufacture — one of the best warranties in the UK market. Electrical components and valve gear carry a 2-year warranty.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cdiv class=\"faq-q\"\u003eIs the S2X hard water compatible?\u003c\/div\u003e\n\u003cdiv class=\"faq-a\"\u003eYes. TITANIUM IMMERSION heaters are used throughout the S2X range, providing superior durability in hard water areas compared to standard stainless steel or incoloy elements. The Duplex stainless steel cylinder body is also inherently scale-resistant.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cdiv class=\"faq-q\"\u003eDoes the S2X need a pump to deliver mains pressure hot water?\u003c\/div\u003e\n\u003cdiv class=\"faq-a\"\u003eNo. The S2X is an unvented cylinder connected directly to the mains cold water supply. Hot water is delivered at mains pressure to all outlets — no pump or header tank is required. This makes it ideal for power showers and multi-outlet simultaneous use.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cdiv class=\"faq-q\"\u003eWhat is the tapping profile and what does XL mean?\u003c\/div\u003e\n\u003cdiv class=\"faq-a\"\u003eThe tapping profile is an ErP (Energy-related Products) classification describing how much hot water the cylinder can deliver in a standardised draw-off test. XL is a high-output profile, confirming the S2X is suitable for large households with multiple simultaneous outlets or high hot water demand.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cdiv class=\"faq-q\"\u003eIs G3 compliance documentation included with the cylinder?\u003c\/div\u003e\n\u003cdiv class=\"faq-a\"\u003eYes — the factory-fitted G3 kit (expansion vessels, PRV, strainer, expansion relief, tundish, drain cock) means all the compliance components are already installed. Your G3-qualified installer will complete the commissioning checklist, which forms the compliance record for Building Regulations Part G3.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cdiv class=\"faq-q\"\u003eCan the S2X be installed in an airing cupboard?\u003c\/div\u003e\n\u003cdiv class=\"faq-a\"\u003eYes. The S2X 300L requires 1780mm height clearance and 595mm diameter, plus 150mm rear clearance. The S-DESIGN concealed pipework keeps the installation tidy.\u003c\/div\u003e\n\u003c\/div\u003e\n\n\u003c\/div\u003e","brand":"OSO Hotwater","offers":[{"title":"Default Title","offer_id":63639983423837,"sku":"11011690","price":1350.0,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0958\/2051\/3629\/files\/OsoSagaXpress150LUnventedDirectHotWaterCylinderPre-Plumbed.jpg?v=1770020582","url":"https:\/\/qualityheating.co.uk\/products\/oso-super-xpress-s2x-300l-direct-unvented-hot-water-cylinder-pre-plumbed-electric","provider":"AIZO Quality Heating","version":"1.0","type":"link"}