{"product_id":"huum-uku-ext-box-uku-extension-box-for-heaters-over-11kw","title":"HUUM UKU Ext Box UKU Extension Box for Heaters over 11kW","description":"\u003c!-- HUUM UKU Extension Box - Required for all HUUM heaters over 12kW --\u003e\u003c!-- SKU: H2003012 | Works with UKU Local Black and UKU WiFi | Mounts outside sauna room --\u003e\u003c!-- Required for: HIVE 12, HIVE 15, HIVE Mini 10.6, CLIFF 11, STEEL 10.5 --\u003e\u003c!-- 5-year warranty | Made in Estonia by HUUM --\u003e\u003c!-- 2 document sections with specific PDF filenames: --\u003e\u003c!-- Installation Manual | PDF: UKU Ext Box Manual 2022.pdf --\u003e\u003c!-- Warranty | PDF: HUUM-Warranty.pdf --\u003e\n\u003cstyle\u003e\n  .sl { font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif; color: #1a2a3a; max-width: 900px; margin: 0 auto; line-height: 1.6; }\n  .sl * { box-sizing: border-box; }\n  .sl h4 { font-weight: 700 !important; color: #0f172a !important; margin: 1.5rem 0 0.5rem; line-height: 1.3; 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align-items: center; gap: 7px; font-size: 14px; font-weight: 500; color: #4a5568; background: #fff; border: 1px solid #d1d5db; border-radius: 5px; padding: 8px 14px; text-decoration: none; }\n  .sl-doc-link:hover { background: #e8f0fa; border-color: #bfd4ef; color: #2563a8; }\n  .sl-divider { border: none; border-top: 1px solid #e2e8f0; margin: 1.75rem 0; }\n  @media (max-width: 768px) {\n    .sl-feat-grid { grid-template-columns: 1fr 1fr; }\n    .sl-spec-grid { grid-template-columns: 1fr; gap: 1.5rem; }\n    .sl-brand1 { grid-template-columns: 1fr; gap: 1rem; padding: 1rem 0; }\n    .sl-brand1 h4 { font-size: 18px !important; }\n  }\n  @media (max-width: 480px) {\n    .sl { padding: 0; }\n    .sl-feat-grid { grid-template-columns: 1fr; gap: 8px; }\n    .sl-feat { padding: 0.8rem 0.9rem; }\n    .sl-inc-grid { grid-template-columns: 1fr; }\n    .sl-spec-grid { gap: 1.25rem; }\n    .sl-spec-table, .sl-spec-table tbody, .sl-spec-table tr, .sl-spec-table td { display: block; width: 100%; }\n    .sl-spec-table { border: none; }\n    .sl-spec-table tr { border: 1px solid #e2e8f0; border-radius: 6px; margin-bottom: 6px; padding: 8px 12px; background: #fff !important; }\n    .sl-spec-table tr:nth-child(odd) { background: #f8fafc !important; }\n    .sl-spec-table td { border: none; padding: 1px 0; }\n    .sl-spec-table td:first-child { font-size: 10px; font-weight: 600; letter-spacing: 0.06em; text-transform: uppercase; color: #64748b; width: 100%; padding-bottom: 2px; }\n    .sl-spec-table td:last-child { font-size: 15px; font-weight: 700 !important; color: #0f172a !important; width: 100%; word-wrap: break-word; overflow-wrap: break-word; }\n    .sl-divider { margin: 1.25rem 0; }\n  }\n\u003c\/style\u003e\n\u003cdiv class=\"sl\"\u003e\n\u003cdiv class=\"sl-desc\"\u003e\n\u003ch2\u003eHUUM UKU Ext Box UKU Extension Box for Heaters over 11kW\u003c\/h2\u003e\n\u003cp\u003eThe HUUM UKU Extension Box is a required component for all HUUM electric sauna heaters over 11kW. It is not a standalone control - the UKU control unit (Local Black or WiFi) must be purchased separately. The Extension Box mounts on the wall outside the sauna room and serves as the electrical intermediary between the high-load heater elements and the UKU control panel, managing the current draw that exceeds the UKU control's direct load capacity. Without the Extension Box, HUUM heaters over 11kW cannot be connected to a UKU control and cannot operate. This listing is for buyers purchasing the Extension Box separately - for example, replacing an existing Extension Box or sourcing it independently from a heater package. Most HUUM heater packages at or above the 12kW threshold include the Extension Box in the bundle.\u003c\/p\u003e\n\u003ch4\u003eWhich HUUM heaters require the Extension Box\u003c\/h4\u003e\n\u003cp\u003eThe Extension Box threshold is over 11kW. HUUM heaters that require the Extension Box include the HIVE 12STU (12kW), HIVE 15STU (15kW), HIVE Mini 10.6STU (10.6kW), CLIFF 11STU (11kW), and STEEL 10.5STU (10.5kW). The HIVE 12, HIVE 15, HIVE Mini 10.6, CLIFF 11, and STEEL 10.5 packages all include the Extension Box. When ordering heaters in this range as standalone heaters (without a package), or when replacing a damaged Extension Box in an existing installation, this listing provides the required component. HUUM heaters at 9kW and below - including the DROP series, HIVE Mini 6 and 9, CLIFF 6 and 9, STEEL 6 and 9, and all other models under 12kW - do not require the Extension Box and operate directly from the UKU control.\u003c\/p\u003e\n\u003ch4\u003eInstallation - outside the sauna room, with the UKU control\u003c\/h4\u003e\n\u003cp\u003eThe Extension Box is mounted on the wall in the electrical installation area outside the sauna room - typically in the changing room, mechanical room, or adjacent wall space where the heater wiring terminates. It is wired between the heater and the UKU control panel and does not need to be inside the sauna room. The UKU Ext Box Manual 2022.pdf (available in the Installation Manual section below) covers the wiring diagram and mounting instructions. A licensed electrician is required for all connections. Do not connect to a GFI\/GFCI breaker. The UKU control unit is sold separately at BathingBrands.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"sl-hook\"\u003eRequired component for all HUUM electric sauna heaters over 11kW. Mounts outside the sauna room. Works with UKU Local Black and UKU WiFi controls. Required for: HIVE 12kW, HIVE 15kW, HIVE Mini 10.6kW, CLIFF 11kW, STEEL 10.5kW. Not required for heaters 9kW and under. UKU control sold separately. 5-year warranty. Made in Estonia by HUUM.\u003c\/div\u003e\n\u003cdiv class=\"sl-badges\"\u003e\n\u003cspan class=\"sl-badge\"\u003eRequired for all HUUM heaters over 11kW\u003c\/span\u003e \u003cspan class=\"sl-badge\"\u003eHIVE 12 and 15 - HIVE Mini 10.6 - CLIFF 11 - STEEL 10.5\u003c\/span\u003e \u003cspan class=\"sl-badge\"\u003eNot required for heaters 9kW and under\u003c\/span\u003e \u003cspan class=\"sl-badge\"\u003eMounts outside sauna room\u003c\/span\u003e \u003cspan class=\"sl-badge\"\u003eWorks with UKU Local Black and UKU WiFi\u003c\/span\u003e \u003cspan class=\"sl-badge\"\u003eUKU control sold separately\u003c\/span\u003e \u003cspan class=\"sl-badge\"\u003e5-year warranty\u003c\/span\u003e \u003cspan class=\"sl-badge\"\u003eMade in Estonia by HUUM\u003c\/span\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"sl-notice\"\u003eℹ️ \u003cstrong\u003eExtension Box included in most high-output HUUM packages.\u003c\/strong\u003e The HIVE 12STU, HIVE 15STU, HIVE Mini 10.6STU, CLIFF 11STU, and STEEL 10.5STU packages all include the Extension Box. This standalone listing is for buyers replacing an existing Extension Box or sourcing it separately from the heater. If ordering a new installation, confirm whether the heater package already includes the Extension Box before purchasing this listing separately.\u003c\/div\u003e\n\u003cdiv class=\"sl-notice-yellow\"\u003e⚠️ \u003cstrong\u003eUKU control is not included and must be purchased separately.\u003c\/strong\u003e The Extension Box is not a sauna control - it is a required intermediary component between the heater and the UKU control. A separate UKU Local Black or UKU WiFi control unit must be purchased to operate the heater. A licensed electrician is required for all wiring connections.\u003c\/div\u003e\n\u003chr class=\"sl-divider\"\u003e\n\u003ch3\u003eSpecifications\u003c\/h3\u003e\n\u003cdiv class=\"sl-spec-grid\"\u003e\n\u003cdiv class=\"sl-spec-tables\"\u003e\n\u003cdiv class=\"sl-spec-block\"\u003e\n\u003ch4\u003eCompatibility\u003c\/h4\u003e\n\u003ctable class=\"sl-spec-table\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eRequired for\u003c\/td\u003e\n\u003ctd\u003eAll HUUM heaters over 11kW\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eNot required for\u003c\/td\u003e\n\u003ctd\u003eHUUM heaters 9kW and under\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCompatible controls\u003c\/td\u003e\n\u003ctd\u003eUKU Local Black and UKU WiFi\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eUKU control included\u003c\/td\u003e\n\u003ctd\u003eNo - sold separately\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"sl-spec-block\"\u003e\n\u003ch4\u003eInstallation\u003c\/h4\u003e\n\u003ctable class=\"sl-spec-table\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eMounting location\u003c\/td\u003e\n\u003ctd\u003eOutside sauna room - wall-mounted\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePosition in circuit\u003c\/td\u003e\n\u003ctd\u003eBetween heater and UKU control\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eElectrician required\u003c\/td\u003e\n\u003ctd\u003eYes - licensed electrician for all connections\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eGFI\/GFCI\u003c\/td\u003e\n\u003ctd\u003eDo not connect to GFI\/GFCI breaker\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"sl-spec-image\"\u003e\n\u003cdiv class=\"sl-spec-block\"\u003e\n\u003ch4\u003eHeaters requiring the Extension Box\u003c\/h4\u003e\n\u003ctable class=\"sl-spec-table\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eHIVE 12STU (12kW)\u003c\/td\u003e\n\u003ctd\u003eExt box required - included in PKG\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eHIVE 15STU (15kW)\u003c\/td\u003e\n\u003ctd\u003eExt box required - included in PKG\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eHIVE Mini 10.6STU (10.6kW)\u003c\/td\u003e\n\u003ctd\u003eExt box required - included in PKG\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCLIFF 11STU (11kW)\u003c\/td\u003e\n\u003ctd\u003eExt box required - included in PKG\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSTEEL 10.5STU (10.5kW)\u003c\/td\u003e\n\u003ctd\u003eExt box required - included in PKG\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"sl-spec-block\"\u003e\n\u003ch4\u003eHeaters NOT requiring the Extension Box\u003c\/h4\u003e\n\u003ctable class=\"sl-spec-table\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eAll DROP models (4.5-9kW)\u003c\/td\u003e\n\u003ctd\u003eNo ext box needed\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eHIVE Mini 6 and 9 (6-9kW)\u003c\/td\u003e\n\u003ctd\u003eNo ext box needed\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCLIFF 6 and 9 (6-9kW)\u003c\/td\u003e\n\u003ctd\u003eNo ext box needed\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSTEEL 6 and 9 (6-9kW)\u003c\/td\u003e\n\u003ctd\u003eNo ext box needed\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCORE series heaters under 12kW\u003c\/td\u003e\n\u003ctd\u003eNo ext box needed\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"sl-spec-block\"\u003e\n\u003ch4\u003eGeneral\u003c\/h4\u003e\n\u003ctable class=\"sl-spec-table\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eWarranty\u003c\/td\u003e\n\u003ctd\u003e5 years\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSKU\u003c\/td\u003e\n\u003ctd\u003eH2003012\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOrigin\u003c\/td\u003e\n\u003ctd\u003eMade in Estonia by HUUM\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003chr class=\"sl-divider\"\u003e\n\u003ch3\u003eWhat's included\u003c\/h3\u003e\n\u003cdiv class=\"sl-inc-grid\"\u003e\n\u003cdiv class=\"sl-inc-item\"\u003eHUUM UKU Extension Box\u003c\/div\u003e\n\u003cdiv class=\"sl-inc-item\"\u003eMounting hardware\u003c\/div\u003e\n\u003cdiv class=\"sl-inc-item\"\u003eInstallation manual\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cp style=\"margin-top: 1rem; font-weight: 500; color: #64748b; font-size: 14px;\"\u003e\u003cstrong\u003eRequired (not included):\u003c\/strong\u003e Compatible HUUM electric sauna heater (over 11kW); UKU control unit (Local Black or WiFi, sold separately at BathingBrands). A licensed electrician is required for all wiring connections. Do not connect to a GFI\/GFCI breaker.\u003c\/p\u003e\n\u003chr class=\"sl-divider\"\u003e\n\u003ch3\u003eWhy the HUUM UKU Extension Box\u003c\/h3\u003e\n\u003cdiv class=\"sl-feat-grid\"\u003e\n\u003cdiv class=\"sl-feat\"\u003e\n\u003cdiv class=\"sl-feat-title\"\u003eRequired for heaters over 11kW\u003c\/div\u003e\n\u003cp\u003eThe UKU control panel manages heater operations up to a direct load limit. For HUUM heaters over 11kW - the HIVE 12, HIVE 15, HIVE Mini 10.6, CLIFF 11, and STEEL 10.5 - the element load exceeds this direct capacity and the Extension Box is required as the intermediary component. Without it, the heater cannot be connected to the UKU control and cannot operate. It is a non-optional component for these models.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"sl-feat\"\u003e\n\u003cdiv class=\"sl-feat-title\"\u003eMounts outside the sauna room\u003c\/div\u003e\n\u003cp\u003eThe Extension Box is installed in the electrical mounting area outside the sauna room - the changing room, mechanical room, or adjacent wall - where it is not exposed to the sauna environment. This placement protects the component from the high heat and humidity inside the sauna and keeps the sauna room itself free of electrical enclosures. Wiring runs from the heater through the sauna wall to the Extension Box and then to the UKU control panel.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"sl-feat\"\u003e\n\u003cdiv class=\"sl-feat-title\"\u003eCompatible with UKU Local Black and UKU WiFi\u003c\/div\u003e\n\u003cp\u003eThe Extension Box works with both UKU control variants - the UKU Local Black for on-site digital operation and the UKU WiFi for HUUM app remote preheat and scheduling on iOS and Android. The UKU control must be purchased separately. For high-output installations where remote preheat of a large sauna room is wanted, the UKU WiFi with the Extension Box delivers the complete control solution.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"sl-feat\"\u003e\n\u003cdiv class=\"sl-feat-title\"\u003eIncluded in most high-output HUUM packages\u003c\/div\u003e\n\u003cp\u003eThe HIVE 12STU, HIVE 15STU, HIVE Mini 10.6STU, CLIFF 11STU, and STEEL 10.5STU packages all include the Extension Box alongside the heater and UKU control. Buyers ordering these packages do not need to purchase this listing separately. This standalone listing serves buyers replacing an Extension Box in an existing installation or sourcing it independently from the heater.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"sl-feat\"\u003e\n\u003cdiv class=\"sl-feat-title\"\u003eSimple installation with licensed electrician\u003c\/div\u003e\n\u003cp\u003eThe Extension Box installs between the heater wiring and the UKU control panel. The UKU Ext Box Manual 2022.pdf in the documents section below provides the wiring diagram and mounting instructions. All connections require a licensed electrician. Do not connect to a GFI\/GFCI breaker. The installation procedure is covered in the heater package IOMs for models that require the Extension Box.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"sl-feat\"\u003e\n\u003cdiv class=\"sl-feat-title\"\u003e5-year warranty - made in Estonia\u003c\/div\u003e\n\u003cp\u003eThe HUUM UKU Extension Box carries a 5-year warranty from the date of purchase covering defects in manufacturing and materials under normal use conditions. It is manufactured in Estonia by HUUM and is the official replacement part for any installation requiring the Extension Box. Proof of purchase from an authorized HUUM dealer is required for warranty claims. We are an authorized HUUM dealer.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003chr class=\"sl-divider\"\u003e\n\u003ch3\u003eAbout HUUM\u003c\/h3\u003e\n\u003cdiv class=\"sl-brand1\"\u003e\n\u003cimg alt=\"HUUM UKU Extension Box required component for HUUM sauna heaters over 12kW wall-mounted outside sauna room\" src=\"https:\/\/prod.cms.bathingbrands.com\/sites\/default\/files\/2025-01\/HUUM-Extension-Box.jpg\" class=\"sl-brand-img\"\u003e\n\u003cdiv\u003e\n\u003cspan class=\"sl-brand-tag\"\u003eMade in Estonia - 5-year warranty\u003c\/span\u003e\n\u003ch4\u003eHUUM UKU Extension Box. Required for HUUM heaters over 11kW. UKU control sold separately.\u003c\/h4\u003e\n\u003cp\u003eHUUM is an Estonian sauna heater company. The UKU Extension Box is the required intermediary component for all HUUM electric sauna heaters over 11kW - the HIVE 12, HIVE 15, HIVE Mini 10.6, CLIFF 11, and STEEL 10.5. It mounts outside the sauna room and connects between the heater elements and the UKU control panel. The UKU control unit (Local Black or WiFi) is sold separately. Most HUUM packages for these heater models include the Extension Box - this standalone listing is for replacement purchases or independent sourcing. We are an authorized HUUM dealer.\u003c\/p\u003e\n\u003cul class=\"sl-check\"\u003e\n\u003cli\u003e\n\u003cstrong\u003eRequired for HUUM heaters over 11kW\u003c\/strong\u003e - HIVE 12\/15, HIVE Mini 10.6, CLIFF 11, STEEL 10.5\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNot required\u003c\/strong\u003e for HUUM heaters 9kW and under\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMounts outside sauna room\u003c\/strong\u003e - between heater and UKU control\u003c\/li\u003e\n\u003cli\u003e\u003cstrong\u003eCompatible with UKU Local Black and UKU WiFi\u003c\/strong\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cstrong\u003e5-year warranty - made in Estonia\u003c\/strong\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003chr class=\"sl-divider\"\u003e\n\u003ch3\u003eManuals and Documents\u003c\/h3\u003e\n\u003cdiv class=\"sl-manual\"\u003e\n\u003cdiv class=\"sl-manual-item\"\u003e\n\u003ch6\u003eInstallation Manual\u003c\/h6\u003e\n\u003ca href=\"https:\/\/prod.cms.bathingbrands.com\/sites\/default\/files\/2022-06\/UKU%20Ext%20Box%20Manual%202022.pdf\" class=\"sl-doc-link\" target=\"_blank\"\u003e \u003csvg width=\"14\" height=\"14\" viewbox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"\u003e\u003cpath d=\"M14 2H6a2 2 0 0 0-2 2v16a2 2 0 0 0 2 2h12a2 2 0 0 0 2-2V8z\"\u003e\u003c\/path\u003e\u003cpolyline points=\"14 2 14 8 20 8\"\u003e\u003c\/polyline\u003e\u003c\/svg\u003e UKU Ext Box Manual 2022.pdf \u003c\/a\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"sl-manual-item\"\u003e\n\u003ch6\u003eWarranty\u003c\/h6\u003e\n\u003ca href=\"https:\/\/prod.cms.bathingbrands.com\/sites\/default\/files\/2025-09\/HUUM-Warranty.pdf\" class=\"sl-doc-link\" target=\"_blank\"\u003e \u003csvg width=\"14\" height=\"14\" viewbox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"\u003e\u003cpath d=\"M14 2H6a2 2 0 0 0-2 2v16a2 2 0 0 0 2 2h12a2 2 0 0 0 2-2V8z\"\u003e\u003c\/path\u003e\u003cpolyline points=\"14 2 14 8 20 8\"\u003e\u003c\/polyline\u003e\u003c\/svg\u003e HUUM-Warranty.pdf \u003c\/a\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003ch3\u003eWarranty\u003c\/h3\u003e\n\u003cdiv class=\"sl-warranty\"\u003e\n\u003ch5\u003e5-year warranty\u003c\/h5\u003e\n\u003cp\u003eThe HUUM UKU Extension Box is covered by HUUM's \u003cstrong\u003e5-year warranty\u003c\/strong\u003e from the date of purchase. The warranty covers defects in manufacturing and materials under normal use conditions. The warranty does not cover damage caused by improper installation, connection to a GFI\/GFCI breaker, use with non-HUUM heaters, or failure to follow the installation guidelines in the Installation Manual. A licensed electrician is required for all electrical connections. Proof of purchase from an authorized HUUM dealer is required for warranty claims. We are an authorized HUUM dealer.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e","brand":"HUUM","offers":[{"title":"Default Title","offer_id":52280955765018,"sku":"H2003012","price":713.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0767\/1690\/0634\/files\/HUUM-Extension-Box.jpg?v=1779694515","url":"https:\/\/mediriser.com\/products\/huum-uku-ext-box-uku-extension-box-for-heaters-over-11kw","provider":"Mediriser","version":"1.0","type":"link"}