Installing range hood... HELP!

CrazyF · 11-17-2009, 02:52 AM

I just got a new under-cabinet range hood to replace the one from my builder. I thought it was going to be a quick swap job, but that wasn't the case.

I have two problems:

1. The vent opening in my cabinet is a wide rectangle (10.5" by 4") that's towards the rear. The new hood's opening is a circle (5 5/16" diameter) that's in the centre.

2. From the builder's installation, I have electrical wires and a ground sticking out of my wall just below the cabinet. The new hood has an electrical plug that comes up right by the vent opening so it needs to be connected to an outlet inside the cabinet.

I'm not at all a handy person, and I'm hoping for a quick and dirty solution. For the first problem, I'm thinking about just hiding the existing rectangular hole by lining the inside of the cabinet with something thin but sturdy (not sure what would work best, maybe just metal). I would then cut out the necessary hole from the cabinet (about half of that hole already being gone because of the rectangular opening) and the lining, and then changing the ducting. Would this work?

As for the electrical problem, I know squat about electrical and adding outlets. What concerns me at this point though is that it doesn't feel like I can pull the existing electrical wires up any higher to reach the inside of the cabinet. Any suggestions?

CustomBuild · 11-17-2009, 06:19 AM

It sounds like you have a solid plan to deal with the ducting. They do make adapters to go from round to rectangular, and with a little patience, the transition should go smoothly.
The electrical is a different issue, though. I would like to point out that more people are killed by 120V than any other voltage. If you are not sure, or not comfortable with anything dealing with electrical, call an electrician. Before you look into changing your wiring around, check the back of the new hood to make sure there aren't optional wiring configurations. Sometimes they provide additional knockouts for different wiring positions. If that is the case, all you have to do is remove the pigtail and plug, and hardwire it just like the old one was. Some user-friendly brands will include instructions for this in the owners manual. If the wiring cannot be reconfigured inside the hood, then your house wiring has to be altered. DON'T EVEN THINK ABOUT WIRE NUTTING ANOTHER WIRE TO THE EXISTING ONE AND POKING THE JUNCTION BACK INTO THE WALL. I have done many remodels, and that seems to be the preferred method. Not only is it unsafe, but it is illegal. The right way to do it is to render the existing wire dead, and to pull a new circuit by fishing it through the wall(through the basement or attic). Make sure that an outlet on that circuit is a GFCI outlet(has test, reset buttons on it), or the circuit breaker is GFCI.
Sorry for the vague description, but I started going into detail, and realized there are so many configurations for your home's wiring, that I would literally be typing all day. If this is something that you feel you can tackle, then my suggestion is to get a basic home wiring book at the library, and familiarize yourself on voltage, wattage, and amperage. Those books give great info on wiring lights, switches, and outlets, and also give sample illustrations on where the wires are run through walls, ceilings and floors. Better yet, go to the box store and buy the book, so you can use it for reference. You are likely to come across a basic wiring problem again in the future.

Bob Mariani · 11-17-2009, 06:23 AM

Call a handyman if you do not feel comfortable doing this work. If you want to do it and you can....Seal the opening in the cabinet with a piece of 1/4" luan. The wire can be moved up in most cases. This must be feed from the lighting circuit not the outlets. If it can not be moved you will need a add a junction box in a location that you can still access as needed and put a blank plate over it. DO NOT just bury the wire splice in the junction box. Use a "old work" box to cut-in the new electrical outlet in the upper wall cabinet as required for you new unit. You can get a duct adapter for the fan to go from square to round connections.

Michael Thomas · 11-17-2009, 07:26 AM

Keep in mind that per 422.16:

(Underlining and formatting mine)

422.16(B)(4)Range Hoods. Range hoods shall be permitted to be cord-and-plug connected with a flexible cord identified as suitable for use on range hoods in the installation instructions of the appliance manufacturer, where all of the following conditions are met:

(1) The flexible cord is terminated with a grounding- type attachment plug.
Exception: A listed range hood distinctly marked to identify it as protected by a system of double insulation, or its equivalent, shall not be required to be terminated with a grounding-type attachment plug.

(2) The length of the cord is not less than 18 in. and not over 36 in.

(3) Receptacles are located to avoid physical damage to the flexible cord.

(4) The receptacle is accessible.

(5) The receptacle is supplied by an individual branch circuit.

CrazyF · 11-17-2009, 03:09 PM

Thanks for the responses. The instruction manual is not the greatest, but it does mention the following about electrical:

"The hood comes equipped with a 5 ft(1.5m) power cord with a NEMA 5-15 molded plug for connection to a 120 VAC, 60 Hz, 15 A Power outlet. This outlet must be located in the duct cover area above the hood.

...

If local codes permit, the power cord may be removed and the hood may be connected to a hard wired electrical connection."

I only see a couple small holes at the rear of the hood, and I don't think the existing jacketed wire can fit through. This is a long shot, but could I run the existing wire splice into the hood, and then setup the power outlet connection inside the hood? Ideally, I'd like to keep the plug intact.

For reference, here are some photos:

Overview

Duct Closeup - Builder used a circle to rectangular adapter, so I'll need more circular ducting.

Underneath View of Cabinet - Existing vent opening and wiring.

Old Hood Opening - The old hood actually had a punchout for a circular opening. I wonder why they went with the rectangular since that meant they needed to use an additional adapter.

New Hood Opening - The cable that you see is the power cord that comes up right by the opening. I'm pretty sure there's some work to be done with screwing things in place (that circular connection piece is loose inside the hood), but the instruction manual mentions nothing about this.

New Hood Rear - You can see one of the small holes where I was hoping to run wires through.

New Hood Stuff? - These came with the hood. The instructions didn't say anything about what to do with them.