Microwaves & Range Hoods installation: two people, the plate, and the vent direction.
A countertop microwave is a plug. An over-the-range microwave is a two-person install that hangs 60 to 80 pounds on a plate screwed to the studs and two bolts through the cabinet above, with its outlet inside that cabinet and its blower pointed outside, up, or back into the room. A range hood is the same mounting problem with a duct. The template in the box — and often not in a surplus box — is what makes it fit.
First use: what is normal
A new machine can do things on its first run that look like a fault and are not. Here is what the makers say is normal, what to do first, and where the line is.
Normal the first time
- A faint electrical or hot-plastic smell for the first few uses.
- On an over-the-range model, a fan that starts by itself and keeps running. It is cooling the microwave and may stay on up to an hour while the range below is in use, and it cannot be turned off then.
Do this first
- 1Take out all packing, inside and out, before the first use.
Where the line is. A burning smell that is not food, or a smell that does not fade after several uses, is not normal: stop using it, unplug it and text us.
What is typically not in the box
Surplus inventory — open box, cancelled order, overstock, minor scratch & dent — is priced for exactly this: a unit can arrive without the small items that ship with a sealed machine. Have these on hand before install day.
The mounting plate, the two long top-cabinet bolts, the paper templates and the exhaust adapter on a surplus over-the-range microwave — the maker sells the install kit by model number.
The charcoal filter for a recirculating (non-vented) install, on many models.
The duct adapter, the damper and the wall or roof cap on a range hood.
The printed manual — download it by model number; the templates are in it.
Power, water, gas, venting, space
What the room has to have before the appliance comes through the door. The manual gives the exact figures for your model; these are the shapes to check.
A grounded 120V, 15 or 20 amp outlet INSIDE the cabinet above the microwave, on its own circuit (the manual's rule); a range hood is usually hardwired to a junction box or plugs in the same way.
The manual's distance from the cooking surface to the bottom of the microwave — typically at least 13 to 18 inches for a microwave, 24 to 30 for a hood over gas — and the cabinet height that gives it; the usual over-the-range cabinet bottom sits 30 inches above the counter.
The mounting plate screws into at least one stud, with toggle anchors for the rest per the manual. Drywall anchors alone are not a mounting.
Three choices, set at install: vented outside through the wall (horizontal) or the roof (vertical) with 3¼ × 10-inch or 6-inch round duct and a damper; or recirculating back into the room through a charcoal filter. The blower is turned to match.
A 30-inch-wide microwave needs a 30-inch opening between the cabinets and the manual's depth; the top cabinet's floor takes the two bolts and the outlet.
The install, step by step
An overview of the manufacturer's own sequence, so you know what a good install looks like whether you watch one or do one. The manual's page for your model is the authority on every figure.
- 1
Find the studs and mark the templates
Stud finder on the back wall, the wall template taped at the manual's height, the top-cabinet template taped under the cabinet. Mark every hole from the templates, not by eye.
- 2
Set the blower for the vent you have
On the bench, before it goes up: the blower assembly rotated to blow out the back (horizontal), out the top (vertical) or forward through the filter (recirculating), and the exhaust adapter or the charcoal filter fitted to match.
- 3
Hang the plate
The plate screwed into the stud(s) and anchored at the template's other holes, level. Run the duct to the wall or roof cap and fit the damper.
- 4
Lift it on — two people
One lifts and tilts the bottom back onto the plate's hooks, the other feeds the cord up through the cabinet hole and starts the two top bolts. Tighten the bolts evenly until the microwave is tight to the cabinet and the wall.
- 5
Plug in and test
Cord into the outlet in the cabinet, then: the turntable, a cup of water for 30 seconds, the light, and the fan on each speed with a tissue at the vent.
- 6
A countertop microwave
A grounded outlet, the manual's clearance on top and at the sides (a few inches, for its own vents), never inside a closed cabinet unless the model is rated for it with its trim kit.
The diagram
Drawn by us, schematic on purpose: the shape of the connection with every part named. Your model's wiring and hookup page in the manual rules on the details.
Mistakes that look like a broken machine
Most first-week calls are one of these. Each is an install item, not a fault — and each is the reason we ask for every function to be tested before the installer leaves.
Hung from drywall anchors alone — the plate pulls out of the wall under the first heavy door swing; a stud is the standard.
The blower never turned — the microwave exhausts into the cabinet above, or blows out the front with the vent to the outside blocked.
Too low over the cooktop — heat from the burners cooks the microwave's electronics within a year; the manual's height is a minimum.
The outlet not in the cabinet — a cord run down the wall to a counter outlet is a code violation and a splash hazard.
The charcoal filter skipped on a recirculating install — the kitchen fills with cooking smell with the fan running.
When a licensed installer is the standard
We recommend professional installation for every appliance we sell. On a microwaves & range hood these are the parts of the job that the code, the permit or the manufacturer's warranty place with a licensed trade.
A new outlet inside the cabinet, or a hardwired hood, is a licensed electrician's job.
A duct run through the roof or an exterior wall with a cap and a damper is an installer's job — flashing and the damper are inspected items on a new run.
Any wall that will not take a stud-mounted plate (a block wall, a window behind the range) needs an installer's mounting plan.
Asked at the counter
Is the mounting plate included?
On a new boxed unit, yes. A surplus or open-box unit can arrive without the plate, the bolts or the templates — look in the box before you buy; the maker sells the install kit by model number.
Do I have to vent it outside?
No — an over-the-range microwave can recirculate through a charcoal filter where no duct exists. Venting outside is better over a gas range; recirculating is the standard where the wall has no duct.
How high above the range does it go?
The manual's minimum from the cooking surface to the bottom of the microwave — most makers say at least 13 to 18 inches; the top of the microwave usually sits 66 inches above the floor.
What your receipt says about installation
Installation & testing
Apex Sales does not perform installation, and we strongly recommend professional installation. Moving or installing an appliance without the proper steps — transported upright and secured, every connection checked, and the unit leveled — can loosen parts or cause problems, and improper installation can void the manufacturer warranty. Have a licensed plumber, electrician, or appliance installer test every function of the unit before they leave, so any issue can be reported right away. Damage caused by improper installation is not covered.
Condition & warranty
All units are surplus inventory (open box, cancelled order, customer return, overstock, or minor scratch & dent). Every unit includes the manufacturer's full factory warranty. Please inspect thoroughly in person before purchasing — cosmetic imperfections or missing accessories are possible.
These pages are a general reference for the appliances we sell. They do not replace the manufacturer's installation instructions, the local building, electrical, plumbing, gas and mechanical codes, or the judgment of a licensed installer. Apex Sales does not perform installations and is not responsible for installation performed by the customer or by a third party. Damage caused by improper installation, transport or connection is not covered by the manufacturer's warranty or by Apex Sales.
When it's not a DIY moment
Everything on these pages is safe to look at with the machine unplugged or the gas shut off. These three are not a look — secure the appliance and call.
Gas smell
Close the appliance's shutoff valve if you can reach it safely, open a window, leave the room, and call the gas utility from outside. No switches, no flames.
Burnt smell, a melted plug, arcing
Shut the breaker off, not just the appliance. A scorched cord, plug or outlet means an electrician looks before anything is plugged back in.
Water that will not stop
Close the supply valve at the appliance first (washer, dishwasher, fridge line, water heater cold inlet), then unplug. Mop before you diagnose.
Text us the model number and what it's doing — we'll point you at the next step.
A fix, a part, or a warranty call — the plate's model and serial plus one line about the symptom is all it takes to tell which.
These pages are educational. Every appliance is a little different — follow the manufacturer's manual and local code, and leave gas, water heater and 240V work to a licensed installer.