{"product_id":"heater-4kw-x300937","title":"MASTER SPAS Heater 4kW  - X300937","description":"\u003ch2\u003eMASTER SPAS Heater 4kW  - X300937\u003c\/h2\u003e\n\u003cp\u003eHeater 4 kW with M7 sensors(V\/N 55950)\u003c\/p\u003e\n\u003ch5\u003eWhat our Experts Think\u003c\/h5\u003e\n\u003cdiv class=\"qMYqUG_convSearchResultHighlightRoot\"\u003e\n\u003cdiv class=\"\" data-turn-id-container=\"request-WEB:4ccad0e2-dbb1-4d1e-b3d2-49509e7bcb81-5\" data-is-intersecting=\"true\"\u003e\n\u003csection class=\"text-token-text-primary w-full focus:outline-none has-data-writing-block:pointer-events-none [\u0026amp;:has([data-writing-block])\u0026gt;*]:pointer-events-auto R6Vx5W_threadScrollVars scroll-mb-[calc(var(--scroll-root-safe-area-inset-bottom,0px)+var(--thread-response-height))] scroll-mt-[calc(var(--header-height)+min(200px,max(70px,20svh)))]\" dir=\"auto\" data-turn-id=\"request-WEB:4ccad0e2-dbb1-4d1e-b3d2-49509e7bcb81-5\" data-turn-id-container=\"request-WEB:4ccad0e2-dbb1-4d1e-b3d2-49509e7bcb81-5\" data-testid=\"conversation-turn-10\" data-turn=\"assistant\"\u003e\n\u003cdiv class=\"text-base my-auto mx-auto pb-10 [--thread-content-margin:var(--thread-content-margin-xs,calc(var(--spacing)*4))] @w-sm\/main:[--thread-content-margin:var(--thread-content-margin-sm,calc(var(--spacing)*6))] @w-lg\/main:[--thread-content-margin:var(--thread-content-margin-lg,calc(var(--spacing)*16))] px-(--thread-content-margin)\"\u003e\n\u003cdiv data-conversation-screenshot-content=\"\" class=\"[--thread-content-max-width:40rem] @w-lg\/main:[--thread-content-max-width:48rem] mx-auto max-w-(--thread-content-max-width) flex-1 group\/turn-messages focus-visible:outline-hidden relative flex w-full min-w-0 flex-col agent-turn\"\u003e\n\u003cdiv class=\"flex max-w-full flex-col gap-4 grow\"\u003e\n\u003cdiv data-message-author-role=\"assistant\" data-message-id=\"d7c7d811-b4c9-455f-899c-15db0eb20330\" data-turn-start-message=\"true\" dir=\"auto\" data-message-model-slug=\"gpt-5-3-mini\" class=\"min-h-8 text-message relative flex w-full flex-col items-end gap-2 text-start break-words whitespace-normal outline-none keyboard-focused:focus-ring [.text-message+\u0026amp;]:mt-1\" tabindex=\"0\"\u003e\n\u003cdiv class=\"flex w-full flex-col gap-1 empty:hidden\"\u003e\n\u003cdiv class=\"markdown prose dark:prose-invert wrap-break-word w-full light markdown-new-styling\"\u003e\n\u003cul data-start=\"28\" data-end=\"1244\" data-is-last-node=\"\" data-is-only-node=\"\"\u003e\n\u003cli data-section-id=\"1lc2jvc\" data-start=\"28\" data-end=\"250\"\u003e\n\u003cstrong data-start=\"30\" data-end=\"66\"\u003eReliable OEM Heating Replacement\u003c\/strong\u003e – The X300937 is a genuine 4kW Master Spas heater assembly designed to restore proper heating performance in compatible swim spas and hot tubs. \u003cspan class=\"\" data-state=\"closed\"\u003e\u003c\/span\u003e\u003cspan aria-hidden=\"true\" class=\"PDq2pG_selectionAnchor\"\u003e\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli data-section-id=\"1eicunb\" data-start=\"251\" data-end=\"460\"\u003e\n\u003cstrong data-start=\"253\" data-end=\"286\"\u003eStable, Efficient Heat Output\u003c\/strong\u003e – 4kW (240V) configuration delivers balanced heating for consistent water temperature maintenance without overloading the spa system. \u003cspan class=\"\" data-state=\"closed\"\u003e\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli data-section-id=\"g5azri\" data-start=\"461\" data-end=\"649\"\u003e\n\u003cstrong data-start=\"463\" data-end=\"492\"\u003eEngineered for M7 Systems\u003c\/strong\u003e – Built for Master Spas setups using M7 sensor technology, ensuring accurate temperature control and safe operation. \u003cspan class=\"\" data-state=\"closed\"\u003e\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli data-section-id=\"gtaeic\" data-start=\"650\" data-end=\"841\"\u003e\n\u003cstrong data-start=\"652\" data-end=\"682\"\u003eDirect Drop-In Replacement\u003c\/strong\u003e – Designed to match original fit and plumbing layout, helping reduce installation time and avoid system modifications. \u003cspan class=\"\" data-state=\"closed\"\u003e\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli data-section-id=\"s0ubcl\" data-start=\"842\" data-end=\"1031\"\u003e\n\u003cstrong data-start=\"844\" data-end=\"882\"\u003eSupports Multiple Master Spa Lines\u003c\/strong\u003e – Commonly used in select H2X Swim Spa and Momentum configurations, making it a widely trusted service part. \u003cspan class=\"\" data-state=\"closed\"\u003e\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli data-section-id=\"aecw0k\" data-start=\"1032\" data-end=\"1244\" data-is-last-node=\"\"\u003e\n\u003cstrong data-start=\"1034\" data-end=\"1064\"\u003eService-Critical Component\u003c\/strong\u003e – Ideal replacement when symptoms include no heat, inconsistent temperature rise, or heater failure due to internal element or sensor faults. \u003cspan class=\"\" data-state=\"delayed-open\" aria-describedby=\"radix-_r_39_\"\u003e\u003c\/span\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/section\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003ch5\u003e\n\u003cbr\u003eQ\u0026amp;A\u003c\/h5\u003e\n\u003cp data-start=\"0\" data-end=\"244\"\u003e\u003cstrong data-start=\"0\" data-end=\"52\"\u003eQ: What is the MASTER SPAS 4kW Heater (X300937)?\u003c\/strong\u003e\u003cbr data-start=\"52\" data-end=\"55\"\u003e\u003cstrong data-start=\"55\" data-end=\"61\"\u003eA:\u003c\/strong\u003e A genuine OEM 4.0kW flow-through electric heater used in Master Spas systems to heat and maintain water temperature in swim spas and hot tubs. \u003cspan class=\"\" data-state=\"closed\"\u003e\u003c\/span\u003e\u003c\/p\u003e\n\u003cp data-start=\"246\" data-end=\"494\"\u003e\u003cstrong data-start=\"246\" data-end=\"269\"\u003eQ: What does it do?\u003c\/strong\u003e\u003cbr data-start=\"269\" data-end=\"272\"\u003e\u003cstrong data-start=\"272\" data-end=\"278\"\u003eA:\u003c\/strong\u003e It heats circulating spa water as part of the control system, working with sensors and the spa pack to maintain set temperature and prevent overheating or dry-fire conditions. \u003cspan class=\"\" data-state=\"closed\"\u003e\u003c\/span\u003e\u003c\/p\u003e\n\u003cp data-start=\"496\" data-end=\"705\"\u003e\u003cstrong data-start=\"496\" data-end=\"535\"\u003eQ: What spas is it compatible with?\u003c\/strong\u003e\u003cbr data-start=\"535\" data-end=\"538\"\u003e\u003cstrong data-start=\"538\" data-end=\"544\"\u003eA:\u003c\/strong\u003e Commonly used in select Master Spas swim spas (including H2X Momentum systems) and models using the M7 control platform. \u003cspan class=\"\" data-state=\"closed\"\u003e\u003c\/span\u003e\u003c\/p\u003e\n\u003cp data-start=\"707\" data-end=\"922\"\u003e\u003cstrong data-start=\"707\" data-end=\"742\"\u003eQ: What are its specifications?\u003c\/strong\u003e\u003cbr data-start=\"742\" data-end=\"745\"\u003e\u003cstrong data-start=\"745\" data-end=\"751\"\u003eA:\u003c\/strong\u003e 4.0kW power rating, 240V operation, stainless steel flow-through design with integrated temperature sensors for system protection. \u003cspan class=\"\" data-state=\"closed\"\u003e\u003c\/span\u003e\u003c\/p\u003e\n\u003cp data-start=\"924\" data-end=\"1130\"\u003e\u003cstrong data-start=\"924\" data-end=\"963\"\u003eQ: Is it a direct replacement part?\u003c\/strong\u003e\u003cbr data-start=\"963\" data-end=\"966\"\u003e\u003cstrong data-start=\"966\" data-end=\"972\"\u003eA:\u003c\/strong\u003e Yes, it replaces original heater assemblies in compatible Master Spas systems and is designed for direct OEM fitment. \u003cspan class=\"\" data-state=\"closed\"\u003e\u003c\/span\u003e\u003c\/p\u003e\n\u003cp data-start=\"1132\" data-end=\"1349\" data-is-last-node=\"\" data-is-only-node=\"\"\u003e\u003cstrong data-start=\"1132\" data-end=\"1181\"\u003eQ: Does it require professional installation?\u003c\/strong\u003e\u003cbr data-start=\"1181\" data-end=\"1184\"\u003e\u003cstrong data-start=\"1184\" data-end=\"1190\"\u003eA:\u003c\/strong\u003e Yes. Correct wiring, sensor connection, and system configuration are required to avoid damage and ensure safe operation.\u003c\/p\u003e\n\u003ch5\u003e\n\u003cbr\u003eMaintenance Tips\u003c\/h5\u003e\n\u003cdiv class=\"qMYqUG_convSearchResultHighlightRoot\"\u003e\n\u003cdiv class=\"\" data-turn-id-container=\"request-WEB:551674be-b0d3-4d53-8efb-dd29a2528df0-25\" data-is-intersecting=\"true\"\u003e\n\u003csection class=\"text-token-text-primary w-full focus:outline-none has-data-writing-block:pointer-events-none [\u0026amp;:has([data-writing-block])\u0026gt;*]:pointer-events-auto R6Vx5W_threadScrollVars scroll-mb-[calc(var(--scroll-root-safe-area-inset-bottom,0px)+var(--thread-response-height))] scroll-mt-[calc(var(--header-height)+min(200px,max(70px,20svh)))]\" dir=\"auto\" data-turn-id=\"request-WEB:551674be-b0d3-4d53-8efb-dd29a2528df0-25\" data-turn-id-container=\"request-WEB:551674be-b0d3-4d53-8efb-dd29a2528df0-25\" data-testid=\"conversation-turn-48\" data-turn=\"assistant\"\u003e\n\u003cdiv class=\"text-base my-auto mx-auto pb-3 [--thread-content-margin:var(--thread-content-margin-xs,calc(var(--spacing)*4))] @w-sm\/main:[--thread-content-margin:var(--thread-content-margin-sm,calc(var(--spacing)*6))] @w-lg\/main:[--thread-content-margin:var(--thread-content-margin-lg,calc(var(--spacing)*16))] px-(--thread-content-margin)\"\u003e\n\u003cdiv data-conversation-screenshot-content=\"\" class=\"[--thread-content-max-width:40rem] @w-lg\/main:[--thread-content-max-width:48rem] mx-auto max-w-(--thread-content-max-width) flex-1 group\/turn-messages focus-visible:outline-hidden relative flex w-full min-w-0 flex-col agent-turn\"\u003e\n\u003cdiv class=\"flex max-w-full flex-col gap-4 grow\"\u003e\n\u003cdiv data-message-author-role=\"assistant\" data-message-id=\"04c63af6-a00a-4dd4-876f-728fe2f55922\" dir=\"auto\" data-message-model-slug=\"gpt-5-3-mini\" class=\"min-h-8 text-message relative flex w-full flex-col items-end gap-2 text-start break-words whitespace-normal outline-none keyboard-focused:focus-ring [.text-message+\u0026amp;]:mt-1\" data-turn-start-message=\"true\" tabindex=\"0\"\u003e\n\u003cdiv class=\"flex w-full flex-col gap-1 empty:hidden\"\u003e\n\u003cdiv class=\"markdown prose dark:prose-invert wrap-break-word w-full light markdown-new-styling\"\u003e\n\u003cul data-start=\"23\" data-end=\"823\" data-is-last-node=\"\" data-is-only-node=\"\"\u003e\n\u003cli data-section-id=\"1e1or4\" data-start=\"23\" data-end=\"153\"\u003eMaintain balanced water chemistry (pH, alkalinity, calcium hardness) to prevent scale buildup and corrosion inside the heater.\u003cspan aria-hidden=\"true\" class=\"PDq2pG_selectionAnchor\"\u003e\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli data-section-id=\"11ajni5\" data-start=\"154\" data-end=\"261\"\u003eClean or replace filters regularly to ensure proper water flow and avoid heater overheating or lockout.\u003c\/li\u003e\n\u003cli data-section-id=\"1p3eiq9\" data-start=\"262\" data-end=\"359\"\u003eEnsure consistent water circulation; never operate the heater with low or no flow conditions.\u003c\/li\u003e\n\u003cli data-section-id=\"vhsxws\" data-start=\"360\" data-end=\"451\"\u003eInspect unions and fittings for leaks or drips that could damage electrical components.\u003c\/li\u003e\n\u003cli data-section-id=\"d0cqum\" data-start=\"452\" data-end=\"544\"\u003eMonitor for error codes or slow heating, which may indicate scaling or flow restriction.\u003c\/li\u003e\n\u003cli data-section-id=\"1q7fg7z\" data-start=\"545\" data-end=\"644\"\u003ePeriodically check for calcium buildup and descale the heater as needed using approved methods.\u003c\/li\u003e\n\u003cli data-section-id=\"1t2w9ij\" data-start=\"645\" data-end=\"742\"\u003eKeep the equipment bay dry and well-ventilated to prevent moisture-related electrical damage.\u003c\/li\u003e\n\u003cli data-section-id=\"1pvq74t\" data-start=\"743\" data-end=\"823\" data-is-last-node=\"\"\u003eAlways turn off power at the breaker before servicing or replacing the heater.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/section\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e","brand":"MASTER SPAS","offers":[{"title":"Default Title","offer_id":45804791595199,"sku":"X300937","price":250.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0683\/5703\/0079\/files\/x300937-340x200.jpg?v=1782930880","url":"https:\/\/se0yig-03.myshopify.com\/products\/heater-4kw-x300937","provider":"Your Outdoor Setup Starts Here","version":"1.0","type":"link"}