--- title: "Installation and setup — Microwave Guides" description: "Mounting a microwave above the cooking surface, venting it outside or letting it recirculate, the trim kit a built-in needs, and the circuit a microwave should…" url: "https://microwaverepair.center/guides/installation-and-setup/" --- Where it goes, how it vents, what it plugs into # Installation and setup guides. Mounting a microwave above the cooking surface, venting it outside or letting it recirculate, the trim kit a built-in needs, and the circuit a microwave should have to itself. ## Installation and setup, guide by guide. A microwave that sits above the cooking surface, inside a cabinet or under a counter depends on three things the owner rarely sees again after installation day: what holds it up, where its air goes and what feeds it power. These guides cover all three, for anyone choosing a new microwave, replacing an old one or wondering why the one on the wall behaves the way it does. [All 18 guides](https://microwaverepair.center/guides/) 6-minute read ### [Mounting a Microwave Above the Cooking Surface: Height, Studs and the Wall Plate](https://microwaverepair.center/guides/mounting-a-microwave-above-the-cooking-surface/) The 30-inch opening and the heights Sharp prints, a wall that carries 110 pounds, toggles that cannot come back out, the outlet in the cabinet above and a two-person hang. 5-minute read ### [Venting a Microwave Outside or Recirculating: Duct, Damper and Charcoal](https://microwaverepair.center/guides/venting-outside-or-recirculating/) Up, back or into the room, metal duct sizes and the 140 equivalent feet, what each elbow and cap costs, where a duct must not end, and how often a charcoal filter is changed. 5-minute read ### [A Dedicated Circuit for the Microwave: Which Kinds Need One and Why](https://microwaverepair.center/guides/a-dedicated-circuit-for-the-microwave/) What GE and Sharp ask of the supply for countertop, hood combination and drawer models, input power against cooking power, the ground pin, extension cords and what a tripping breaker tells you. ## Where it goes, how it vents, what it plugs into. Mounting comes first because it is the part that can fall. A microwave hood combination hangs from a plate on the wall and from screws into the cabinet above it, and the makers' sheets set the height, the studs and the load the wall has to carry. Venting comes next: the same fan can push air outside through a metal duct or recirculate it through a charcoal filter, and the choice is made before the microwave goes up. Power is the quiet one. Microwaves draw more from the wall than their cooking power suggests, the built-in kinds usually want a circuit of their own, and none of them belongs on an extension cord. A breaker that trips every morning is often an installation question rather than a broken microwave. These guides describe what a good installation looks like so you can judge one; they are not a substitute for the installation instructions that came with your model, and the wiring itself is an electrician's job. Every figure is taken from the makers' own installation sheets and support pages, printed under the section it supports. [Not sure where to start?](https://microwaverepair.center/guides/#start-here) ### The short answer Mounting a Microwave Above the Cooking Surface: Height, Studs and the Wall Plate Microwave mounting height is set by the installation instructions: in Sharp's, a 30-inch-wide space, at least 30 inches from the cooking surface to the cabinet above, 66 inches or more from the floor and a 2-inch gap above the backsplash. ### The short answer Venting a Microwave Outside or Recirculating: Duct, Damper and Charcoal To vent a microwave outside, the fan is set to blow up or back into a metal duct of 3-1/4 by 10 inches or 6 inches round, with no more than 140 equivalent feet including elbows and caps. ### The short answer A Dedicated Circuit for the Microwave: Which Kinds Need One and Why A dedicated circuit for a microwave means a 120-volt branch circuit serving only that appliance, with a grounded three-prong outlet and a 15- or 20-amp breaker. ## When reading is not enough. If the checks in these guides did not settle it, the visit picks up from there, stop by stop. [What repairs cost](https://microwaverepair.center/cost/) 1. 01 A cup of water, timed 2. 02 The price before the work 3. 03 Usual parts on board 4. 04 Heating again before we leave ## The problems these answer. Each has a page of its own, with the causes in the order worth checking. [All 17 problems](https://microwaverepair.center/problems/) Problem ### Microwave Door Won't Latch Shut 6 causes, cheapest first Problem ### Microwave Vent Fan Not Pulling Steam 6 causes, cheapest first Stop using it ### Microwave Trips the Breaker or Blows a Fuse 6 causes, cheapest first Problem ### Loud Hum, Buzz or Grinding From a Microwave 6 causes, cheapest first For the heart of your home. ## Questions about installation and setup. ### Can I install a microwave hood combination myself? Hanging one is within reach of a handy owner with a helper, provided a grounded outlet already sits in the cabinet above and the studs line up. A new outlet or circuit, and any cut through an outside wall or roof, are jobs for an electrician or a contractor. ### Which is better, venting outside or recirculating? Venting outside removes heat, steam and smoke; a charcoal filter only catches odors. Recirculating is the practical choice where no duct route exists, as long as the charcoal filter is replaced on schedule. ### Does a microwave need its own circuit? GE says its hood combinations should always have one, and Sharp asks for a separate circuit for its hood combinations and recommends one for its drawers. For a countertop model it is strongly advisable if the circuit also feeds a toaster or kettle. ### What should I check before the installer arrives? The width and height of the opening against the model's diagram, where the studs are, where the outlet will go and whether the unit will vent outside. Have the installation instructions printed or downloaded. ## The other sections. Split by what you are trying to find out rather than by which part of the appliance it concerns. [All guides](https://microwaverepair.center/guides/) What the microwave is telling you ### [Common problems](https://microwaverepair.center/guides/common-problems/) - [Why a microwave sparks: stray metal, a spattered waveguide cover and a scarred cavity](https://microwaverepair.center/guides/why-a-microwave-sparks/) - [Microwave runs but food stays cold: settings, the door latch and the high-voltage side](https://microwaverepair.center/guides/microwave-runs-but-food-stays-cold/) - [Why the turntable stopped: the coupler, the roller ring and the motor beneath](https://microwaverepair.center/guides/why-the-turntable-stopped/) Checks you can make at the door ### [Troubleshooting](https://microwaverepair.center/guides/troubleshooting/) - [Microwave checks before booking: breaker, locks, a cup of water and the door](https://microwaverepair.center/guides/microwave-checks-before-booking/) - [Reading the microwave display: power-cut messages, locks, demo mode and service codes](https://microwaverepair.center/guides/reading-the-microwave-display/) - [Find the microwave model plate on a hood combination, built-in, drawer or countertop](https://microwaverepair.center/guides/find-the-microwave-model-plate/) Habits that keep it heating for years ### [Maintenance and prevention](https://microwaverepair.center/guides/maintenance-and-prevention/) - [Cleaning the grease filters and changing the charcoal filter](https://microwaverepair.center/guides/cleaning-the-grease-and-charcoal-filters/) - [Keeping the cavity and the waveguide cover clean](https://microwaverepair.center/guides/keeping-the-cavity-and-waveguide-cover-clean/) - [A yearly microwave check: door, heating, fan and mounting](https://microwaverepair.center/guides/a-yearly-microwave-check/) Keeping people and the kitchen safe ### [Sparks, fire and the door](https://microwaverepair.center/guides/safety-and-food/) - [A Fire Inside the Microwave: Door Shut, Power Off, Then Watch](https://microwaverepair.center/guides/a-fire-inside-the-microwave/) - [A Microwave Door That Will Not Seal: Unplug It and Leave It Off](https://microwaverepair.center/guides/a-microwave-door-that-will-not-seal/) - [What Is Safe to Put in a Microwave: Dishes, Covers, Foil and Water](https://microwaverepair.center/guides/what-is-safe-to-put-in-a-microwave/) Which kind of microwave, and fix or replace ### [Choosing and comparing](https://microwaverepair.center/guides/choosing-and-comparing/) - [Hood combination, built-in or drawer: choosing where the microwave lives](https://microwaverepair.center/guides/hood-combination-built-in-or-drawer/) - [Speed oven or plain microwave: what browning heat adds, and what it asks](https://microwaverepair.center/guides/speed-oven-or-plain-microwave/) - [Repair or replace a microwave: the door, the part and the opening it fills](https://microwaverepair.center/guides/repair-or-replace-a-microwave/) Not sure which section? ### Start from your question The four questions most visits start with, each with the guide that answers it. 18 guides Where to start Where to start --- **[Read on the site: Installation and setup — Microwave Guides](https://microwaverepair.center/guides/installation-and-setup/)** **[Book a visit with MicrowaveRepair.center](https://microwaverepair.center/schedule/)**