{"id":1349,"date":"2026-04-11T06:48:27","date_gmt":"2026-04-11T05:48:27","guid":{"rendered":"https:\/\/strover.com\/?p=1349"},"modified":"2026-05-18T06:51:46","modified_gmt":"2026-05-18T05:51:46","slug":"smart-switch-upgrade-for-immersion-heater","status":"publish","type":"post","link":"https:\/\/strover.com\/?p=1349","title":{"rendered":"Smart Switch Upgrade for Immersion Heater"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">This project converts an existing hot water immersion heater from a simple on \/ off manual switch to a configurable system with remote access. The goal was simple:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Keep the design <strong>safe<\/strong><\/li>\n\n\n\n<li>Keep it <strong>simple<\/strong><\/li>\n\n\n\n<li>Keep costs low<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>CAUTION<\/strong>: This blog documents the steps taken by a curious DIYer and may not be suitable for your use case. Electrical installations can be dangerous. Seek help from a professional electrician or plumber if you are at all unsure.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">The Setup<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">The system consists of:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>A <strong>Linky smart meter and consumer unit<\/strong> <\/li>\n\n\n\n<li>A <strong>ballon d\u2019eau chaude<\/strong> (immersion heater)<\/li>\n<\/ul>\n\n\n\n<figure class=\"wp-block-gallery has-nested-images columns-default is-cropped wp-block-gallery-1 is-layout-flex wp-block-gallery-is-layout-flex\">\n<figure class=\"wp-block-image size-large\"><a href=\"https:\/\/particulier.edf.fr\/en\/home\/contract-and-consumption\/meter\/linky-meter.html\"><img loading=\"lazy\" decoding=\"async\" width=\"640\" height=\"640\" data-id=\"1368\" src=\"http:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6401.jpeg\" alt=\"\" class=\"wp-image-1368\" srcset=\"https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6401.jpeg 640w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6401-300x300.jpeg 300w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6401-150x150.jpeg 150w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6401-100x100.jpeg 100w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><\/a><figcaption class=\"wp-element-caption\">Linky Smart Meter &amp; Consumer Unit<\/figcaption><\/figure>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"480\" height=\"640\" data-id=\"1367\" src=\"http:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6402.jpeg\" alt=\"\" class=\"wp-image-1367\" srcset=\"https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6402.jpeg 480w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6402-225x300.jpeg 225w\" sizes=\"auto, (max-width: 480px) 100vw, 480px\" \/><figcaption class=\"wp-element-caption\">Ballon d&#8217;eau chaude sanitaire (immersion heater)<\/figcaption><\/figure>\n<\/figure>\n\n\n\n<h2 class=\"wp-block-heading\">Options Considered<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Option A \u2014 Smart switch at the heater<\/strong><br>Install a smart switch directly inside the immersion heater.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Option B \u2014 Smart switch in the consumer unit<\/strong><br>Control the heater circuit upstream using existing switching hardware.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Option C \u2014 Hire a professional<\/strong><br>Always sensible\u2014but less appealing for a curious DIYer (and not always easy in France).<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Chosen Approach<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Option B was selected.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Option A<\/strong> requires a high-current smart switch (~16A for a 3000W heater) and opening up an old immersion heater\u2014less desirable from a safety perspective.<\/li>\n\n\n\n<li><strong>Option B<\/strong> uses the existing relay (contactor), switching only the <strong>low-current control side<\/strong>, making it significantly safer.<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Prerequisites<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Before starting the installation, a couple of practical checks are performed.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">WiFi Signal Strength<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Since the <strong>smart switch<\/strong> relies on WiFi for control and scheduling, it\u2019s important to ensure there is a <strong>reliable signal at the consumer unit<\/strong>.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Check signal strength using my phone while standing next to the consumer unit<\/li>\n\n\n\n<li>A stable connection (at least 2\u20133 bars) is recommended<\/li>\n\n\n\n<li>If the signal was weak, a WiFi extender or repositioning of the router may work.<\/li>\n\n\n\n<li>An alternative approach is to install a Shelly smart switch that supports Zigbee or Matter.<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">Contacteur Jour\/Nuit<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">In France, immersion heaters are often controlled by a <em>Contacteur Jour\/Nuit<\/em>, designed to run during off-peak hours. This device is a type of electrical <strong>contactor<\/strong>.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">It has 3 modes:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>I<\/strong> \u2192 Always On <\/li>\n\n\n\n<li><strong>Auto<\/strong> \u2192 Controlled (normally by off-peak tariff) <\/li>\n\n\n\n<li><strong>0<\/strong> \u2192 Always Off<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">In this setup, we use a standard EDF tariff, so the Auto function is unused. This makes it perfect for repurposing with a smart switch via terminals <strong>A1 and A2<\/strong>.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Some definitions:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Contactor<\/strong> \u2192 a specific type of <strong>relay designed for high-power loads<\/strong> (such as this immersion heater)<\/li>\n\n\n\n<li><strong>Relay<\/strong> \u2192 a general term for an electrically operated switch <\/li>\n\n\n\n<li><strong>Contacteur Jour\/Nuit<\/strong> \u2192 the French term for a <strong>contactor with a control circuit<\/strong> (often tied to off-peak tariffs)<\/li>\n<\/ul>\n\n\n\n<figure class=\"wp-block-gallery has-nested-images columns-default is-cropped wp-block-gallery-2 is-layout-flex wp-block-gallery-is-layout-flex\">\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"480\" height=\"640\" data-id=\"1372\" src=\"http:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6397.jpeg\" alt=\"\" class=\"wp-image-1372\" srcset=\"https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6397.jpeg 480w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6397-225x300.jpeg 225w\" sizes=\"auto, (max-width: 480px) 100vw, 480px\" \/><figcaption class=\"wp-element-caption\">Contacteur Jour\/Nuit<\/figcaption><\/figure>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"480\" height=\"640\" data-id=\"1371\" src=\"http:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6398.jpeg\" alt=\"\" class=\"wp-image-1371\" srcset=\"https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6398.jpeg 480w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6398-225x300.jpeg 225w\" sizes=\"auto, (max-width: 480px) 100vw, 480px\" \/><figcaption class=\"wp-element-caption\">Circuit Breaker<\/figcaption><\/figure>\n<\/figure>\n\n\n\n<h2 class=\"wp-block-heading\">Circuit Breaker<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">The heater circuit is protected by a dedicated breaker.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Conveniently:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>It provides <strong>spare terminals<\/strong> for live and neutral<\/li>\n\n\n\n<li>These are used to power the smart switch<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">Components<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">The following components were used to complete the installation. All are readily available and relatively inexpensive.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Shelly 1 Gen 3  \u2013 Smart Switch<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">A compact WiFi-enabled relay used to control the contactor. It supports <strong>dry contact operation<\/strong>, meaning it can switch a circuit without supplying power itself\u2014ideal for safely controlling the low-current coil of the relay.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Cost: <strong>\u00a311.17<\/strong><\/li>\n\n\n\n<li>\ud83d\udc49 <a href=\"https:\/\/www.shelly.com\/products\/shelly-1-gen3\" target=\"_blank\" rel=\"noopener\" title=\"\">https:\/\/www.shelly.com\/products\/shelly-1-gen3<\/a><\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">DIN Rail Holder for Shelly<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">A 3D-printed DIN rail mount used to securely install the Shelly inside the consumer unit, keeping the wiring tidy and compliant with enclosure standards.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Cost: <strong>\u00a312.46<\/strong><\/li>\n\n\n\n<li>\ud83d\udc49 <a href=\"https:\/\/amzn.eu\/d\/02aAzuu3\" target=\"_blank\" rel=\"noopener\" title=\"\">https:\/\/amzn.eu\/d\/02aAzuu3<\/a><\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">2.5mm\u00b2 Solid Core Electrical Cable<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Standard domestic wiring cable, chosen to match the existing wiring within the consumer unit. Using consistent cable sizing helps maintain clarity and compliance.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\ud83d\udc49 <a href=\"https:\/\/www.cef.co.uk\/catalogue\/products\/4204732\" target=\"_blank\" rel=\"noopener\" title=\"\">https:\/\/www.cef.co.uk\/catalogue\/products\/4204737<\/a><\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">Wago 221 Connectors (x2)<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Lever connectors used to safely join and distribute wires within the enclosure. These are reliable, reusable, and ideal for compact installations.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\ud83d\udc49 <a href=\"https:\/\/www.tlc-direct.co.uk\/Products\/WA413C.html?source=msn&amp;campaign=smart_shopping&amp;ad_id=80539417266453&amp;kw=&amp;network=o&amp;matchtype=e&amp;product_id=WA413C&amp;product_partition_id=pla-2332339040861990&amp;test=finalurl\" target=\"_blank\" rel=\"noopener\" title=\"\">https:\/\/www.tlc-direct.co.uk\/Products\/WA413C.html<\/a><\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">Total Cost<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Approximate total: <strong>\u00a335<\/strong><\/p>\n\n\n\n<figure class=\"wp-block-gallery has-nested-images columns-default is-cropped wp-block-gallery-3 is-layout-flex wp-block-gallery-is-layout-flex\">\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"1024\" data-id=\"1408\" src=\"http:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6435-1024x1024.jpeg\" alt=\"\" class=\"wp-image-1408\" srcset=\"https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6435-1024x1024.jpeg 1024w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6435-300x300.jpeg 300w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6435-150x150.jpeg 150w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6435-768x768.jpeg 768w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6435-100x100.jpeg 100w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6435.jpeg 1080w\" sizes=\"auto, (max-width: 706px) 89vw, (max-width: 767px) 82vw, 740px\" \/><\/figure>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"540\" height=\"540\" data-id=\"1407\" src=\"http:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6437.webp\" alt=\"\" class=\"wp-image-1407\" srcset=\"https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6437.webp 540w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6437-300x300.webp 300w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6437-150x150.webp 150w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6437-100x100.webp 100w\" sizes=\"auto, (max-width: 540px) 100vw, 540px\" \/><\/figure>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"540\" height=\"540\" data-id=\"1406\" src=\"http:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6436.webp\" alt=\"\" class=\"wp-image-1406\" srcset=\"https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6436.webp 540w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6436-300x300.webp 300w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6436-150x150.webp 150w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6436-100x100.webp 100w\" sizes=\"auto, (max-width: 540px) 100vw, 540px\" \/><\/figure>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"497\" height=\"497\" data-id=\"1411\" src=\"http:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6439.jpeg\" alt=\"\" class=\"wp-image-1411\" srcset=\"https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6439.jpeg 497w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6439-300x300.jpeg 300w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6439-150x150.jpeg 150w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6439-100x100.jpeg 100w\" sizes=\"auto, (max-width: 497px) 100vw, 497px\" \/><\/figure>\n\n\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" data-id=\"1447\" src=\"http:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6447.jpeg\" alt=\"\" class=\"wp-image-1447\"\/><\/figure>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"703\" height=\"703\" data-id=\"1429\" src=\"http:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6444.jpeg\" alt=\"\" class=\"wp-image-1429\" srcset=\"https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6444.jpeg 703w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6444-300x300.jpeg 300w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6444-150x150.jpeg 150w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6444-100x100.jpeg 100w\" sizes=\"auto, (max-width: 703px) 100vw, 703px\" \/><\/figure>\n<\/figure>\n\n\n\n<h2 class=\"wp-block-heading\">Wiring<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">The Shelly is used to control the <strong>coil of the contactor<\/strong>, not the heater directly.<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><td class=\"has-text-align-center\" data-align=\"center\">#<\/td><td>Shelly<\/td><td>Contacteur<\/td><td>Circuit Breaker<\/td><\/tr><tr><td class=\"has-text-align-center\" data-align=\"center\">1<\/td><td>Neutral<\/td><td>A2<\/td><td>Neutral<\/td><\/tr><tr><td class=\"has-text-align-center\" data-align=\"center\">2<\/td><td>Live (L)<\/td><td>\u2014<\/td><td>Live<\/td><\/tr><tr><td class=\"has-text-align-center\" data-align=\"center\">3<\/td><td>Input (I)<\/td><td>\u2014<\/td><td>Linked to Live (L)<\/td><\/tr><tr><td class=\"has-text-align-center\" data-align=\"center\">4<\/td><td>Output Live (O)<\/td><td>A1<\/td><td>\u2014<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<figure class=\"wp-block-gallery has-nested-images columns-default is-cropped wp-block-gallery-4 is-layout-flex wp-block-gallery-is-layout-flex\">\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"1024\" data-id=\"1369\" src=\"http:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6400-1024x1024.jpeg\" alt=\"\" class=\"wp-image-1369\" srcset=\"https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6400-1024x1024.jpeg 1024w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6400-300x300.jpeg 300w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6400-150x150.jpeg 150w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6400-768x768.jpeg 768w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6400-100x100.jpeg 100w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6400.jpeg 1431w\" sizes=\"auto, (max-width: 706px) 89vw, (max-width: 767px) 82vw, 740px\" \/><figcaption class=\"wp-element-caption\">Area highlighted where smart switch is installed<\/figcaption><\/figure>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"640\" height=\"640\" data-id=\"1370\" src=\"http:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6399-1.jpeg\" alt=\"\" class=\"wp-image-1370\" srcset=\"https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6399-1.jpeg 640w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6399-1-300x300.jpeg 300w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6399-1-150x150.jpeg 150w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6399-1-100x100.jpeg 100w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><figcaption class=\"wp-element-caption\">Smart switch installed<\/figcaption><\/figure>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"768\" height=\"1024\" data-id=\"1364\" src=\"http:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6399-768x1024.jpeg\" alt=\"\" class=\"wp-image-1364\" srcset=\"https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6399-768x1025.jpeg 768w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6399-225x300.jpeg 225w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6399.jpeg 1009w\" sizes=\"auto, (max-width: 706px) 89vw, (max-width: 767px) 82vw, 740px\" \/><figcaption class=\"wp-element-caption\">Close-up view<\/figcaption><\/figure>\n<\/figure>\n\n\n\n<h2 class=\"wp-block-heading\">Set Up &amp; Testing<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Power was restored carefully in stages:<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>System powered with heater isolated<\/li>\n\n\n\n<li>Manual modes (0 and I) tested<\/li>\n\n\n\n<li>Auto mode tested with Shelly OFF<\/li>\n\n\n\n<li>Shelly control enabled and verified<\/li>\n<\/ol>\n\n\n\n<p class=\"wp-block-paragraph\">Each step checked for:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>correct switching<\/li>\n\n\n\n<li>no overheating<\/li>\n\n\n\n<li>no breaker trips<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Connecting Shelly to the App<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">The Shelly device is configured via the mobile app over WiFi.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A step-by-step guide is available here:<br>\ud83d\udc49 <a href=\"https:\/\/kb.shelly.cloud\/knowledge-base\/shelly-1-gen3\" target=\"_blank\" rel=\"noopener\" title=\"\">https:\/\/kb.shelly.cloud\/knowledge-base\/shelly-1-gen3<\/a><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">This covers:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>powering up the device<\/li>\n\n\n\n<li>connecting to its temporary WiFi network<\/li>\n\n\n\n<li>adding it to your home network<\/li>\n\n\n\n<li>configuring schedules and timers<\/li>\n<\/ul>\n\n\n\n<figure class=\"wp-block-gallery has-nested-images columns-default is-cropped wp-block-gallery-5 is-layout-flex wp-block-gallery-is-layout-flex\">\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"1024\" data-id=\"1422\" src=\"http:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6416_CoPilot.png\" alt=\"\" class=\"wp-image-1422\" srcset=\"https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6416_CoPilot.png 1024w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6416_CoPilot-300x300.png 300w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6416_CoPilot-150x150.png 150w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6416_CoPilot-768x768.png 768w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6416_CoPilot-100x100.png 100w\" sizes=\"auto, (max-width: 706px) 89vw, (max-width: 767px) 82vw, 740px\" \/><\/figure>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"750\" height=\"750\" data-id=\"1366\" src=\"http:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6415.jpeg\" alt=\"\" class=\"wp-image-1366\" srcset=\"https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6415.jpeg 750w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6415-300x300.jpeg 300w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6415-150x150.jpeg 150w, https:\/\/strover.com\/wp-content\/uploads\/2026\/04\/IMG_6415-100x100.jpeg 100w\" sizes=\"auto, (max-width: 706px) 89vw, (max-width: 767px) 82vw, 740px\" \/><\/figure>\n<\/figure>\n\n\n\n<h2 class=\"wp-block-heading\">Result<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">The immersion heater is now:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Electrically safe (no high-current switching through the smart device)<\/li>\n\n\n\n<li>Remotely controllable<\/li>\n\n\n\n<li>Scheduled via app<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">Final Thoughts<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">This approach strikes a great balance between:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Safety<\/strong> (using the contactor properly)<\/li>\n\n\n\n<li><strong>Cost<\/strong> (~\u00a335 &amp; 1-hour to install)<\/li>\n\n\n\n<li><strong>Flexibility<\/strong> (full smart control)<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">A simple upgrade that makes a big difference to everyday energy use.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Upgrade your immersion heater with a Shelly 1 Gen 3 smart switch. 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