{"product_id":"intatec-28mm-straight-by-pass-valve","title":"Inta Heat Pump Automatic Differential Bypass Valve 28mm — ABPS28CP Straight ABPA28CP Angled — Compression Fittings","description":"\u003cdiv style=\"font-size:16px;font-family:Arial,Helvetica,sans-serif;color:#1a1a1a;max-width:900px;margin:0 auto;line-height:1.6;\"\u003e\n\n  \u003c!-- ── INTRO ─────────────────────────────────────────────────────── --\u003e\n  \u003cp style=\"margin:0 0 18px;\"\u003e\n    The \u003cstrong\u003eInta 28mm Automatic Differential Bypass Valve\u003c\/strong\u003e is a \u003cstrong\u003emanually adjustable differential-pressure bypass valve for 28mm heating and heat pump pipework\u003c\/strong\u003e, available in two configurations: \u003cstrong\u003eABPS28CP (straight)\u003c\/strong\u003e for in-line installation on a bypass spur, and \u003cstrong\u003eABPA28CP (angled)\u003c\/strong\u003e for fitting at a 90° corner between parallel flow and return connections. Designed by Intatec specifically for heat pump systems that use 28mm primary pipework, these valves stabilise circulation, maintain the required minimum flow rate through the heat pump, and protect the pump from running against a closed head when zone valves or TRVs shut down. The \u003cstrong\u003evisual adjustment dial sets the bypass opening differential pressure from 0.1 to 0.5 bar\u003c\/strong\u003e — matched to the system's pump curve and the heat pump manufacturer's minimum flow specification. Maximum working pressure \u003cstrong\u003e10 bar\u003c\/strong\u003e, maximum temperature \u003cstrong\u003e100°C\u003c\/strong\u003e, flow capacity \u003cstrong\u003e1 to 5 m³\/h\u003c\/strong\u003e.\n  \u003c\/p\u003e\n\n  \u003c!-- ── AMBER VARIANT CALLOUT ─────────────────────────────────────── --\u003e\n  \u003cdiv style=\"border-left:4px solid #f59e0b;background:#fff8e1;padding:10px 16px;margin-bottom:22px;border-radius:0 6px 6px 0;\"\u003e\n    \u003cstrong style=\"color:#b45309;\"\u003e⚡ ABPS28CP vs ABPA28CP — Which configuration?\u003c\/strong\u003e\u003cbr\u003e\n    \u003cstrong\u003eABPS28CP (straight):\u003c\/strong\u003e Inlet and outlet are in-line — fits on a short straight bypass spur connecting two parallel sections of 28mm flow and return pipework. The most compact installation where flow and return run alongside each other.\u003cbr\u003e\n    \u003cstrong\u003eABPA28CP (angled):\u003c\/strong\u003e Inlet and outlet at 90° — fits directly at a corner between 28mm flow and return pipework without additional bends or offsets. Most commonly used adjacent to the heat pump or in airing cupboard installations where flow and return enter from different wall faces.\u003cbr\u003e\n    Both variants are functionally identical — the choice is determined entirely by the pipework layout at the installation point.\n  \u003c\/div\u003e\n\n  \u003c!-- ── TEAL HEAT PUMP NOTE ───────────────────────────────────────── --\u003e\n  \u003cdiv style=\"border-left:4px solid #008377CF;background:#e6f4f3;padding:10px 16px;margin-bottom:22px;border-radius:0 6px 6px 0;\"\u003e\n    \u003cstrong style=\"color:#005c54;\"\u003eℹ Why 28mm? Heat pump systems require larger pipework\u003c\/strong\u003e\u003cbr\u003e\n    Air source heat pump systems operate at lower flow temperatures and higher flow rates than gas boilers — achieving the same heat output requires moving significantly more water. For this reason, heat pump primary circuits are typically designed in \u003cstrong\u003e28mm rather than 22mm pipework\u003c\/strong\u003e to minimise pressure drop and ensure the pump can deliver the manufacturer's minimum required flow rate. The ABPS28CP \/ ABPA28CP are the correct bypass valves for these 28mm primary circuits; using a 22mm bypass valve with reducing adaptors would create unnecessary restriction and pressure drop.\n  \u003c\/div\u003e\n\n  \u003c!-- ── FEATURES GRID ──────────────────────────────────────────────── --\u003e\n  \u003cdiv style=\"background:#008377CF;color:#fff;font-weight:600;font-size:15px;padding:10px 16px;border-radius:6px 6px 0 0;\"\u003e\n    Features \u0026amp; Benefits\n  \u003c\/div\u003e\n  \u003cdiv style=\"display:grid;grid-template-columns:repeat(auto-fill,minmax(255px,1fr));gap:12px;background:#e6f4f3;padding:14px;border-radius:0 0 6px 6px;margin-bottom:22px;\"\u003e\n\n    \u003cdiv style=\"background:#f0faf9;border:1px solid #c8e6e3;border-radius:6px;padding:13px;\"\u003e\n      \u003cdiv style=\"font-weight:700;color:#008377CF;margin-bottom:5px;\"\u003e✔ Adjustable 0.1–0.5 Bar — Visual Dial\u003c\/div\u003e\n      \u003cdiv style=\"font-size:14px;\"\u003eThe bypass opening pressure is set via a \u003cstrong\u003evisual dial on the valve body\u003c\/strong\u003e, adjustable from 0.1 to 0.5 bar differential pressure. This allows the installer to calibrate the bypass precisely to the heat pump's pump operating curve and the manufacturer's stated minimum flow requirement. A setting of 0.2–0.3 bar is typical for most domestic heat pump systems; the correct value should be confirmed against the pump curve and system hydraulic calculations at commissioning.\u003c\/div\u003e\n    \u003c\/div\u003e\n\n    \u003cdiv style=\"background:#f0faf9;border:1px solid #c8e6e3;border-radius:6px;padding:13px;\"\u003e\n      \u003cdiv style=\"font-weight:700;color:#008377CF;margin-bottom:5px;\"\u003e✔ Protects the Heat Pump — Minimum Flow Maintained\u003c\/div\u003e\n      \u003cdiv style=\"font-size:14px;\"\u003eHeat pump manufacturers specify a \u003cstrong\u003eminimum flow rate through the heat exchanger\u003c\/strong\u003e at all times — if flow falls below this threshold, the heat pump triggers a fault, goes into low-flow protection mode, or reduces output. When zone valves close down or UFH circuits limit flow, the bypass opens to maintain circulation. This is particularly important in multi-zone heat pump installations where individual zones can be off while others are calling — the bypass ensures the heat pump circuit always has adequate flow.\u003c\/div\u003e\n    \u003c\/div\u003e\n\n    \u003cdiv style=\"background:#f0faf9;border:1px solid #c8e6e3;border-radius:6px;padding:13px;\"\u003e\n      \u003cdiv style=\"font-weight:700;color:#008377CF;margin-bottom:5px;\"\u003e✔ Protects the Circulation Pump\u003c\/div\u003e\n      \u003cdiv style=\"font-size:14px;\"\u003eWithout a bypass, a circulation pump running against a closed or near-closed system creates a condition known as \u003cstrong\u003eclosed-head pumping\u003c\/strong\u003e — the pump circulates in a tight loop with minimal flow, overheating the motor, and creating high differential pressure that stresses pipework joints and heat exchanger plates. The bypass valve prevents this by providing an alternative flow path as soon as the differential pressure reaches the set point.\u003c\/div\u003e\n    \u003c\/div\u003e\n\n    \u003cdiv style=\"background:#f0faf9;border:1px solid #c8e6e3;border-radius:6px;padding:13px;\"\u003e\n      \u003cdiv style=\"font-weight:700;color:#008377CF;margin-bottom:5px;\"\u003e✔ 1–5 m³\/h Flow Capacity\u003c\/div\u003e\n      \u003cdiv style=\"font-size:14px;\"\u003eA flow capacity range of \u003cstrong\u003e1 to 5 m³\/h (approximately 17–83 litres\/minute)\u003c\/strong\u003e covers the full range of domestic heat pump primary circuit flow rates — from a modest 3–5 kW micro-system to a 16 kW multi-zone installation running at maximum duty. The 28mm bore ensures low resistance even at higher flow rates.\u003c\/div\u003e\n    \u003c\/div\u003e\n\n    \u003cdiv style=\"background:#f0faf9;border:1px solid #c8e6e3;border-radius:6px;padding:13px;\"\u003e\n      \u003cdiv style=\"font-weight:700;color:#008377CF;margin-bottom:5px;\"\u003e✔ 28mm Compression — No Specialist Tooling\u003c\/div\u003e\n      \u003cdiv style=\"font-size:14px;\"\u003eStandard \u003cstrong\u003e28mm compression fittings\u003c\/strong\u003e connect directly to copper tube without soldering or specialist tools — appropriate for retrofit on existing 28mm pipework or new installations. The compression connections also allow the valve to be removed for replacement without cutting the pipework, simplifying future servicing.\u003c\/div\u003e\n    \u003c\/div\u003e\n\n    \u003cdiv style=\"background:#f0faf9;border:1px solid #c8e6e3;border-radius:6px;padding:13px;\"\u003e\n      \u003cdiv style=\"font-weight:700;color:#008377CF;margin-bottom:5px;\"\u003e✔ Reduces System Noise from Zone Valves\u003c\/div\u003e\n      \u003cdiv style=\"font-size:14px;\"\u003eAs UFH circuits and zone valves close down during a heat pump heating cycle, increasing flow restriction can cause \u003cstrong\u003epipework noise and pump whine\u003c\/strong\u003e. The bypass valve opens progressively to maintain a stable system pressure and prevents the pressure surges that propagate as noise through 28mm pipework runs. This is particularly noticeable in open-plan properties where pipework passes through habitable areas.\u003c\/div\u003e\n    \u003c\/div\u003e\n\n  \u003c\/div\u003e\n\n  \u003c!-- ── SPEC TABLE ─────────────────────────────────────────────────── --\u003e\n  \u003cdiv style=\"background:#008377CF;color:#fff;font-weight:600;font-size:15px;padding:10px 16px;border-radius:6px 6px 0 0;\"\u003e\n    Technical Specifications\n  \u003c\/div\u003e\n  \u003ctable style=\"width:100%;border-collapse:collapse;margin-bottom:8px;font-size:14px;\"\u003e\n    \u003ctbody\u003e\n      \u003ctr style=\"background:#f0faf9;\"\u003e\n\u003ctd style=\"padding:9px 14px;font-weight:600;width:44%;border-bottom:1px solid #c8e6e3;\"\u003eManufacturer\u003c\/td\u003e\n\u003ctd style=\"padding:9px 14px;border-bottom:1px solid #c8e6e3;\"\u003eIntatec (Inta)\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr style=\"background:#fff;\"\u003e\n\u003ctd style=\"padding:9px 14px;font-weight:600;border-bottom:1px solid #c8e6e3;\"\u003ePart Numbers\u003c\/td\u003e\n\u003ctd style=\"padding:9px 14px;border-bottom:1px solid #c8e6e3;\"\u003e\n\u003cstrong\u003eABPS28CP\u003c\/strong\u003e (straight) \/ \u003cstrong\u003eABPA28CP\u003c\/strong\u003e (angled)\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr style=\"background:#f0faf9;\"\u003e\n\u003ctd style=\"padding:9px 14px;font-weight:600;border-bottom:1px solid #c8e6e3;\"\u003eConnection Size\u003c\/td\u003e\n\u003ctd style=\"padding:9px 14px;border-bottom:1px solid #c8e6e3;\"\u003e28mm compression\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr style=\"background:#fff;\"\u003e\n\u003ctd style=\"padding:9px 14px;font-weight:600;border-bottom:1px solid #c8e6e3;\"\u003eConfiguration\u003c\/td\u003e\n\u003ctd style=\"padding:9px 14px;border-bottom:1px solid #c8e6e3;\"\u003eABPS28CP: straight (in-line) · ABPA28CP: angled (90°)\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr style=\"background:#f0faf9;\"\u003e\n\u003ctd style=\"padding:9px 14px;font-weight:600;border-bottom:1px solid #c8e6e3;\"\u003eDifferential Pressure Range\u003c\/td\u003e\n\u003ctd style=\"padding:9px 14px;border-bottom:1px solid #c8e6e3;\"\u003e\n\u003cstrong\u003e0.1 – 0.5 bar\u003c\/strong\u003e (adjustable via visual dial)\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr style=\"background:#fff;\"\u003e\n\u003ctd style=\"padding:9px 14px;font-weight:600;border-bottom:1px solid #c8e6e3;\"\u003eFlow Capacity\u003c\/td\u003e\n\u003ctd style=\"padding:9px 14px;border-bottom:1px solid #c8e6e3;\"\u003e\n\u003cstrong\u003e1 – 5 m³\/h\u003c\/strong\u003e (approx. 17–83 litres\/min)\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr style=\"background:#f0faf9;\"\u003e\n\u003ctd style=\"padding:9px 14px;font-weight:600;border-bottom:1px solid #c8e6e3;\"\u003eMax Working Pressure\u003c\/td\u003e\n\u003ctd style=\"padding:9px 14px;border-bottom:1px solid #c8e6e3;\"\u003e10 bar\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr style=\"background:#fff;\"\u003e\n\u003ctd style=\"padding:9px 14px;font-weight:600;border-bottom:1px solid #c8e6e3;\"\u003eMax Working Temperature\u003c\/td\u003e\n\u003ctd style=\"padding:9px 14px;border-bottom:1px solid #c8e6e3;\"\u003e100°C\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr style=\"background:#f0faf9;\"\u003e\n\u003ctd style=\"padding:9px 14px;font-weight:600;border-bottom:1px solid #c8e6e3;\"\u003eOperation Type\u003c\/td\u003e\n\u003ctd style=\"padding:9px 14px;border-bottom:1px solid #c8e6e3;\"\u003eAutomatic differential pressure — no electrical connection\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr style=\"background:#fff;\"\u003e\n\u003ctd style=\"padding:9px 14px;font-weight:600;border-bottom:1px solid #c8e6e3;\"\u003eTypical Applications\u003c\/td\u003e\n\u003ctd style=\"padding:9px 14px;border-bottom:1px solid #c8e6e3;\"\u003eAir source heat pump primary circuits; multi-zone CH systems; UFH manifold installations; systems with zone valves on 28mm pipework\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/div\u003e","brand":"Inta","offers":[{"title":"Straight","offer_id":64133783093597,"sku":"ABPS28CP","price":19.0,"currency_code":"GBP","in_stock":true},{"title":"Angled","offer_id":64133783126365,"sku":"ABPA28CP","price":19.0,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0958\/2051\/3629\/files\/HeatPumpAutoBypassValve28mmhpbpv28a.webp?v=1770397788","url":"https:\/\/qualityheating.co.uk\/products\/intatec-28mm-straight-by-pass-valve","provider":"AIZO Quality Heating","version":"1.0","type":"link"}