Are you interested in an over the range microwave installation? Dolce Electric Co has staffed in-office electricians in Mesa AZ that you can consult with today, Tuesday, July 7th, 2020, free of cost. Having installed hundreds of over the stove microwaves and being voted best electricians Mesa AZ our local Mesa electricians will answer all of your questions and provide you with the information you’re in search of. Give them a call today between 8:00 AM and 5:00 PM, you’ll be happy you did!
Microwave Installation Steps
There are six steps to an over the range microwave oven installation. Following these steps in order will make the installation of your microwave easier. Attention should be given to each step to insure a safe and professional installation. Remove everything stored in the upper cabinet before beginning the installation.
1. Remove existing over the range hood
Turn off the circuit breaker that supplies power to the range hood and verify that it is off (make a note of what else is now off, you’ll need to know this later). Disconnect the wires and cap the wires from the wall to prevent electrical injury. Disconnect duct work if present (be careful, it’s sharp and gloves should be used). Find the mounting screws and remove them, this will allow you to take the range hood out completely.
2. Install over range microwave outlet
Most over the range microwave ovens require a standard 3-prong 120 volt outlet for electrical power. This outlet will need to be located directly above the microwave (in the upper cabinet when present). It’s always best to provide a dedicated circuit for this outlet but it’s not always financially practical or even possible depending on the location of your fuse box and design of your home. Other options include using the existing power wires from the old range hood or tapping into a different kitchen circuit. When making an installation utilizing existing power it’s important to know how much additional power is needed and how much power is available to avoid overloading the existing electrical circuit.
Determining how much additional power is needed:
Each microwave has its power demand listed somewhere on the unit, typically inside the door. It will be referred to in KW or kilowatts. Most microwaves require around 1.5KW or 1500 watts give or take a little depending on the size and manufacture. To find amperage divide watts by volts or 1500 watts ÷ 120 volts = 12.5 amps as an example.
Determining how much power is available:
Kitchen circuits will be rated at either 15 or 20 amps. A 15 amp circuit will provide a total of 1800 watts (15 amps x 120 volts = 1800 watts) and a 20 amp circuit will provide a total of 2400 watts (20 amps x 120 volts = 2400 watts). Assuming you are planning on using an existing 15 amp circuit that was providing power to the range hood and your new microwave requires 1500 watts you would have 300 watts remaining to power everything else on that circuit. If the existing circuit is a 20 amp circuit you would have 900 watts remaining for everything else on that circuit. Going above these maximum wattage thresholds will cause the circuit breaker to trip.
When you turned off the power to disconnect the range hood you turned off other things as well. Add up the wattage of all the other powerless devices, appliances and lighting and add that amount to the wattage of the microwave. If you are under the maximum available wattage everything will work fine. If your total wattage is above the maximum available wattage you will need to limit using anything else at the same time as the microwave to keep the circuit breaker from tripping. In this case a new dedicated circuit is recommended.
If lighting is on the circuit you can lower the total power demand on the circuit by replacing conventional incandescent light bulbs with compact fluorescent or LED light bulbs. This can sometimes free up enough power to make the circuit usable for your microwave outlet.
If you need additional help Dolce Electric Company schedules a local electrician in Mesa AZ that homeowners can call for free over the phone assistance in determining available power. Our in-office Mesa AZ electricians are available from 8:00 AM until 5:00 PM today, Tuesday, July 7th, 2020.
3. Attach the oven wall support plate
This is the part that holds the microwave up. It’s important that the support plate is properly secured to the wall insuring it will be able to bear the weight of the microwave. Here are the six steps to attaching the wall support plate:
- Measuring across the top of the mounting area, mark the center and draw a vertical line (slightly longer than the height of the bottom of the support plate) down the wall using the edge of a level.
- Locate the studs inside the wall using a stud sensor and mark them on the wall’s surface.
- Tape the wall template in place aligning its center marks with the ones on the wall.
- Mark the corner holes and at least one other hole that aligns with a wall stud.
- Remove the template and drill the holes that align with a stud using a 3/16” drill bit for lag bolts and drill the other holes with a 3/8” drill bit for toggle bolts.
- Hold the mounting plate against the wall, align it with the center mark and secure it in place.
It is imperative that the support plate is secured to at least one wall stud for strength. If no attachment to a stud is made safety is compromised and the microwave can fall. It can sometime be difficult to find the studs when tile or other materials are on the wall. In these cases look in the cabinet above to see where it has been attached to the stud and measure or plum down accordingly. Masonry drill bits will be needed when working on a tiled surface.
4. Prepare the bottom of the upper cabinet for mounting
The upper cabinet will require holes for securing the microwave from above, a hole for the power cord and in some cases a hole will need to be cut for duct work.
- Measuring across the bottom of the upper cabinet mark the center and tape the upper cabinet template into place.
- Mark the screw holes for attaching the microwave to the upper cabinet
- Mark the hole for the power cord
- If ventilating from above mark the duct hole
- Remove template and drill upper mounting screw holes (typically 3/8”)
- Drill the power cord hole (needs to be large enough for the cord to pass through)
- Cut out duct hole if applicable
Drilling these holes slowly with sharp drill bits and using light pressure will reduce splintering on the interior of the cabinet.
5. Adjust the blower motor for venting
Determine what type of unit is being installed, some are non-vented and others are outside exhaust vented. Non-vented units don’t require any adjustment but outside vented units require the blower motor to be set up for either top or behind venting depending on where the duct work is. To make this adjustment the blower motor will need to be gently lifted out and repositioned with the exhaust ports facing the correct direction. Care should be taken because the motor wires are not very long and excessive pulling can cause internal damage. The unit’s damper plate will need to be removed and reinstalled too.
6. Attach the over range microwave
Some microwaves are heavier than others but the assistance of a second person will make this final step easier.
- Place the upper mounting screws inside the upper cabinet with the washers slid over the screws. Do not put them into the drilled holes yet. Place a screwdriver in the cabinet too.
- Lift the microwave into place catching the support tabs on the wall mounting plate. The microwave will need to be tilted slightly with the front lower than the back.
- While the microwave is tilted and loosely hinged on the mounting plate, work the power cord through the hole until all of the slack is in the upper cabinet.
- Pivot the front of the microwave (while still hinged to the support plate) until the top front is touching the upper cabinet and install the upper mounting screws. Do not fully tighten them until all screws are threaded into the unit, slight adjustments may be required. Any existing duct work will need to be aligned at this point. Duct tape may be needed to seal the connecting duct work after the unit is fully secured.
- Check to see if the unit is evenly centered in the space and tighten the upper mounting screws with equal torque until the top of the unit is snug against the bottom of the upper cabinet.
The microwave is now fully suspended and it can be plugged in. Install any filters or other components at this time. If you have not done it already, remember to turn the circuit back on.
If you would like more information about installing a microwave oven over your cooktop, Dolce Electric Company schedules an electrician Mesa AZ homeowners can consult with free of charge. Our in-office electricians in Mesa are available from 8:00 AM until 5:00 PM today, Tuesday, July 7th, 2020, and free estimates are available.