{"product_id":"oso-acc200-superstream-200l-cold-water-accumulator-tank","title":"OSO Acc200 SuperStream 200L Cold Water Accumulator Tank","description":"\u003cstyle\u003e\n  .dw-wrap{font-family:inherit;color:inherit;line-height:1.7;font-size:16px}\n  .dw-wrap p,.dw-wrap li,.dw-wrap td,.dw-wrap th{font-size:16px!important;line-height:1.7}\n  .dw-wrap h2{font-size:22px!important;font-weight:700;color:#1a3a5c;border-bottom:3px solid #008377;padding-bottom:6px;margin:2rem 0 1rem;line-height:1.3}\n  .dw-wrap h3{font-size:17px!important;font-weight:700;color:#1a3a5c;margin:1.2rem 0 0.4rem;line-height:1.4}\n  .dw-wrap p{margin:0 0 1rem}\n  .dw-wrap ul{padding-left:1.5rem;margin:0 0 1rem}\n  .dw-wrap ul li{margin-bottom:0.5rem}\n  .dw-badge{display:inline-block;font-size:13px!important;font-weight:700;border-radius:4px;padding:2px 10px;margin-right:5px;margin-bottom:4px;vertical-align:middle}\n  .dw-badge.blue{background:#008377;color:#fff}\n  .dw-badge.navy{background:#1a3a5c;color:#fff}\n  .dw-badge.teal{background:#0d9488;color:#fff}\n  .dw-badge.green{background:#1a7a3c;color:#fff}\n  .dw-badge.grey{background:#555;color:#fff}\n  .dw-intro-box{background:#e0f2fe;border-left:4px solid #008377CF;padding:1.1rem 1.4rem;border-radius:0 6px 6px 0;margin-bottom:1.5rem}\n  .dw-intro-box p{margin:0!important}\n  .dw-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(230px,1fr));gap:0.85rem;margin-bottom:1.2rem}\n  .dw-card{background:#e0f2fe;border:1px solid #90caf9;border-radius:6px;padding:1rem 1.1rem;line-height:1.6}\n  .dw-card strong{display:block;color:#1a3a5c;margin-bottom:0.35rem;font-size:16px!important}\n  .dw-info-box{background:#f0fdf4;border:1px solid #86efac;border-radius:6px;padding:1rem 1.2rem;margin:1.2rem 0}\n  .dw-info-box p{margin:0 0 0.5rem!important;color:#065f46;font-weight:700}\n  .dw-comp-box{background:#fff3cd;border:1px solid #ffc107;border-radius:5px;padding:0.9rem 1.1rem;margin:0.8rem 0}\n  .dw-spec-table{width:100%;border-collapse:collapse;margin-bottom:1.5rem}\n  .dw-spec-table th{background:#1a3a5c;color:#fff!important;text-align:left;padding:0.7rem 1rem;font-weight:700;font-size:16px!important}\n  .dw-spec-table td{padding:0.6rem 1rem;border-bottom:1px solid #bde0f5;vertical-align:top;font-size:16px!important}\n  .dw-spec-table tr:nth-child(even) td{background:#e0f2fe}\n  .dw-spec-table td:first-child{font-weight:600;color:#111;width:44%}\n  .dw-faq-item{border-bottom:1px solid #bde0f5;padding:0.9rem 0}\n  .dw-faq-item:last-child{border-bottom:none}\n  .dw-faq-item strong{color:#1a3a5c;font-size:16px!important;display:block;margin-bottom:0.3rem}\n  .dw-contents-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(200px,1fr));gap:0.6rem;margin-bottom:1.2rem}\n  .dw-contents-item{background:#f0f9ff;border:1px solid #bde0f5;border-radius:5px;padding:0.6rem 0.9rem;font-size:15px!important}\n\u003c\/style\u003e\n\n\u003cdiv class=\"dw-wrap\"\u003e\n\u003cdiv style=\"margin-bottom:1rem\"\u003e\n\u003cspan class=\"dw-badge blue\"\u003e11007351\u003c\/span\u003e\u003cspan class=\"dw-badge navy\"\u003eAcc200\u003c\/span\u003e\u003cspan class=\"dw-badge teal\"\u003eSuperStream\u003c\/span\u003e\u003cspan class=\"dw-badge green\"\u003e200 L\u003c\/span\u003e\u003cspan class=\"dw-badge grey\"\u003eCold Water Accumulator\u003c\/span\u003e\u003cspan class=\"dw-badge grey\"\u003ePower-Free Booster\u003c\/span\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"dw-intro-box\"\u003e\u003cp\u003e\u003cstrong\u003eOSO Acc200 SuperStream 200 L Accumulator\u003c\/strong\u003e — Patented power-free cold Water Accumulator Tank booster with CAD2 diaphragm technology | Delivers up to ~80 l\/min extra flow | Silent, zero-energy, zero-maintenance solution for medium-demand homes | Lightweight composite tank | Horizontal or vertical install (horizontal requires cradle – sold separately) | WRAS-approved butyl membrane | 5-year warranty | Requires Upstream Kit 22\/28 mm (sold separately)\u003c\/p\u003e\u003c\/div\u003e\n\u003cdiv class=\"dw-comp-box\"\u003e\n\u003cstrong\u003e✅ Double the usable volume of the Acc130 – perfect for family homes or 2–3 bathroom properties\u003c\/strong\u003eProvides a larger “reserve” of boosted water for simultaneous use of multiple showers, baths, kitchen taps and appliances. No electricity = no running costs, no noise, no servicing. Expandable with additional units for even higher performance.\u003c\/div\u003e\n\u003cp\u003eThe OSO SuperStream Acc200 is the mid-range model in the acclaimed SuperStream series — designed specifically for properties where the Acc130’s 130 L capacity might be stretched during peak times (e.g. morning rush with 2 showers + kitchen running). It delivers the same revolutionary performance as the smaller unit but with double the total volume and approximately double the usable stored water (~100 L effective at 1.5 bar differential), giving noticeably longer high-flow periods before relying solely on incoming mains.\u003c\/p\u003e\n\u003cp\u003eLike all SuperStream accumulators, it uses the patented CAD2 (Controlled Action Diaphragm 2) technology: a food-grade butyl diaphragm separates stored potable water from a nitrogen-precharged air chamber. When demand exceeds supply, the diaphragm gently pushes stored water into the system — boosting flow and stabilising pressure without any pumps, electricity, noise or maintenance. The result is powerful, consistent performance across multiple outlets, even on weak or restricted mains supplies common in many UK homes.\u003c\/p\u003e\n\u003cp\u003eThe corrosion-proof composite fiberglass\/epoxy shell is exceptionally strong yet weighs only 22 kg empty — making it far easier to manoeuvre into lofts, cupboards or plant rooms than traditional steel vessels. A key advantage over the Acc130 is the option for horizontal mounting (using the dedicated Horizontal Cradle 11007329), which is invaluable in space-restricted installations.\u003c\/p\u003e\n\u003ch2\u003eWhat Makes the SuperStream Acc200 Special?\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eZero Running Costs Forever\u003c\/strong\u003e — No electricity, no pump servicing, no filters — truly sustainable and budget-friendly long-term.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCompletely Silent\u003c\/strong\u003e — 0 dB operation — perfect for bedrooms, quiet homes or night-time use (unlike booster pumps).\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePatented CAD2 Diaphragm\u003c\/strong\u003e — Prevents waterlogging, delivers even pressure, maximises usable volume (~100 L effective).\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHorizontal or Vertical Flexibility\u003c\/strong\u003e — Unique in the range — horizontal option saves valuable headroom in lofts\/cupboards (cradle required).\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLightweight \u0026amp; Corrosion-Proof\u003c\/strong\u003e — Composite construction outperforms steel tanks in longevity and ease of handling.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eExpandable to Any Size\u003c\/strong\u003e — Link multiple units in parallel for commercial-level flow without replacing the system.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWRAS \u0026amp; Regulation Compliant\u003c\/strong\u003e — Butyl membrane (WRAS 1501305) safe for drinking water systems; fully meets UK water bylaws.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eKey Features\u003c\/h2\u003e\n\u003cdiv class=\"dw-grid\"\u003e\n\u003cdiv class=\"dw-card\"\u003e\n\u003cstrong\u003eHigh Flow Boost\u003c\/strong\u003eSupplements mains by up to ~80 l\/min — ideal for 2–3 simultaneous outlets.\u003c\/div\u003e\n\u003cdiv class=\"dw-card\"\u003e\n\u003cstrong\u003eZero Energy \u0026amp; Zero Noise\u003c\/strong\u003ePassive system — no power, no sound, performs in outages.\u003c\/div\u003e\n\u003cdiv class=\"dw-card\"\u003e\n\u003cstrong\u003eLarger Usable Reserve\u003c\/strong\u003e~100 L effective storage at typical differential — longer high-flow periods.\u003c\/div\u003e\n\u003cdiv class=\"dw-card\"\u003e\n\u003cstrong\u003eHorizontal Mounting Option\u003c\/strong\u003eUse with Cradle (11007329) for low-height spaces.\u003c\/div\u003e\n\u003cdiv class=\"dw-card\"\u003e\n\u003cstrong\u003eHygienic WRAS Membrane\u003c\/strong\u003eButyl rubber approved for potable water (ref 1501305).\u003c\/div\u003e\n\u003cdiv class=\"dw-card\"\u003e\n\u003cstrong\u003eComposite Construction\u003c\/strong\u003eFibreglass\/epoxy — 22 kg empty, corrosion-free, 5-year warranty.\u003c\/div\u003e\n\u003cdiv class=\"dw-card\"\u003e\n\u003cstrong\u003ePre-Charge Adjustable\u003c\/strong\u003eFactory 1.4 bar — fine-tune on site for best results.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003ch2\u003eTechnical Specifications\u003c\/h2\u003e\n\u003ctable class=\"dw-spec-table\"\u003e\u003ctbody\u003e\n\u003ctr\u003e\n\u003cth\u003eSpecification\u003c\/th\u003e\n\u003cth\u003eValue\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePart Number\u003c\/td\u003e\n\u003ctd\u003e11007351\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTotal Vessel Volume\u003c\/td\u003e\n\u003ctd\u003e200 litres\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eUsable Water Volume\u003c\/td\u003e\n\u003ctd\u003e~100 litres (at 1.5 bar differential pressure)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDimensions (Ø × Height – vertical)\u003c\/td\u003e\n\u003ctd\u003e542 × 1098 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eEmpty Weight\u003c\/td\u003e\n\u003ctd\u003e22 kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFull Weight (approx.)\u003c\/td\u003e\n\u003ctd\u003e122 kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eConnections\u003c\/td\u003e\n\u003ctd\u003e1¼\" BSP male × 28 mm compression\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMax Working Pressure\u003c\/td\u003e\n\u003ctd\u003e8.6 bar (860 kPa)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePre-charge Pressure\u003c\/td\u003e\n\u003ctd\u003e1.4 bar (factory — adjustable)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMax Boost Head (closed valve)\u003c\/td\u003e\n\u003ctd\u003e4.3 bar\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWater Temperature Range\u003c\/td\u003e\n\u003ctd\u003e4 °C to 35 °C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAmbient Temperature Max\u003c\/td\u003e\n\u003ctd\u003e40 °C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMembrane Material\u003c\/td\u003e\n\u003ctd\u003eButyl rubber (WRAS 1501305)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTank Construction\u003c\/td\u003e\n\u003ctd\u003eContinuous strand fibreglass + epoxy resin\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWarranty\u003c\/td\u003e\n\u003ctd\u003e5 years (vessel \u0026amp; diaphragm)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\u003c\/table\u003e\n\u003ch2\u003eWhat's in the Box\u003c\/h2\u003e\n\u003cdiv class=\"dw-contents-grid\"\u003e\n\u003cdiv class=\"dw-contents-item\"\u003e✔ 1 × Acc200 SuperStream Accumulator Vessel\u003c\/div\u003e\n\u003cdiv class=\"dw-contents-item\"\u003e✔ 1¼\" BSP male to 28 mm compression fittings\u003c\/div\u003e\n\u003cdiv class=\"dw-contents-item\"\u003e✔ Pre-charge adjustment \u0026amp; orientation guide\u003c\/div\u003e\n\u003cdiv class=\"dw-contents-item\"\u003e✔ Full installation \u0026amp; commissioning manual\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"dw-info-box\"\u003e\u003cp\u003e✅ Essential companions: Upstream Kit 22\/28 mm (11007380) for the first unit + Add-on Kit (11007327) for each extra accumulator. For horizontal install use Horizontal Cradle (11007329). For very low incoming pressure add Charger Pump (11007348).\u003c\/p\u003e\u003c\/div\u003e\n\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\n\u003cdiv class=\"dw-faq-item\"\u003e\n\u003cstrong\u003eDoes the Acc200 require electricity or regular servicing?\u003c\/strong\u003eNo — 100% passive, silent (0 dB), zero power consumption and zero maintenance for the 5-year warranty period and beyond.\u003c\/div\u003e\n\u003cdiv class=\"dw-faq-item\"\u003e\n\u003cstrong\u003eHow much extra flow\/pressure does it provide?\u003c\/strong\u003eSupplements incoming mains by up to ~80 litres per minute (pipework dependent) — excellent for 2–3 simultaneous high-flow outlets without noticeable drop-off.\u003c\/div\u003e\n\u003cdiv class=\"dw-faq-item\"\u003e\n\u003cstrong\u003eIs it safe for drinking water systems?\u003c\/strong\u003eYes — WRAS-approved butyl membrane (ref 1501305) stores wholesome potable water with no treatment chemicals or risk of contamination.\u003c\/div\u003e\n\u003cdiv class=\"dw-faq-item\"\u003e\n\u003cstrong\u003eCan I install it horizontally?\u003c\/strong\u003eYes — unlike the Acc130, the Acc200 supports horizontal mounting when used with the dedicated Horizontal Cradle (11007329) — perfect for lofts or low-ceiling plant rooms.\u003c\/div\u003e\n\u003cdiv class=\"dw-faq-item\"\u003e\n\u003cstrong\u003eHow many units can I connect together?\u003c\/strong\u003eAs many as needed — parallel installation is straightforward. Use one Upstream Kit for the first accumulator and one Add-on Kit per additional unit.\u003c\/div\u003e\n\u003cdiv class=\"dw-faq-item\"\u003e\n\u003cstrong\u003eWill it help my combi boiler or unvented cylinder?\u003c\/strong\u003eAbsolutely — many customers fit the Acc200 to eliminate pressure\/fl ow complaints on weak mains, improving hot water delivery and recovery times.\u003c\/div\u003e\n\u003cdiv class=\"dw-faq-item\"\u003e\n\u003cstrong\u003eWhat if my mains pressure is below 1.5–2 bar?\u003c\/strong\u003eFor dynamic pressures consistently below ~2 bar, combine with the SuperStream Charger Pump (11007348) to raise incoming pressure — then let the accumulator handle peak demand boosting.\u003c\/div\u003e\n\u003cdiv class=\"dw-faq-item\"\u003e\n\u003cstrong\u003eHow long does the air pre-charge last?\u003c\/strong\u003eThe nitrogen pre-charge is sealed for the life of the vessel. Simple pressure checks\/adjustments are possible but rarely needed in normal use.\u003c\/div\u003e\n\u003cdiv class=\"dw-faq-item\"\u003e\n\u003cstrong\u003eIs the composite tank more durable than steel?\u003c\/strong\u003eYes — fibreglass\/epoxy construction is highly corrosion-resistant, lighter to handle, and less prone to internal rust or failure over time compared to traditional steel vessels.\u003c\/div\u003e\n\u003c\/div\u003e","brand":"OSO Hotwater","offers":[{"title":"Default Title","offer_id":63733965979997,"sku":"Acc200","price":900.0,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0958\/2051\/3629\/files\/OSOSuperStreamColdWaterAccumulatorTank.jpg?v=1772780702","url":"https:\/\/qualityheating.co.uk\/products\/oso-acc200-superstream-200l-cold-water-accumulator-tank","provider":"AIZO Quality Heating","version":"1.0","type":"link"}