Furnace blower motor question

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I'm getting a small generator (3500 watt) and have a question that may be kind of simplistic but please bear with me. Electricity is not my strong point. My wife asked me to put a new light bulb in the lamp the other day but I couldn't finish the job because I couldn't find the lightbulb installation instructions on the package. Like I'm an engineer or something.

Anyway, our furnace uses natural gas and the blower motor is of course wired in to the breaker panel. Assuming we still have natural gas but the power goes out (serious in minus 40 weather) is it as simple as cutting the connection to the panel box and installing a plug on the wires so we can plug it into the generator? Is there anything else I need to do or watch out for? Thanks.

-- Craig (craig@ccinet.ab.ca), September 18, 1998

Answers

Yes. Check out the thread above called "Operation of Home Pc's, television, stereo etc by generator power." Pay particular attention to the startup load (3 or 4 times running load) requirements for electric motors. Check the tag on the blower motor for ratings. Should be pretty well covered in that other thread.

Also, you might want to figure out a way to get the connections set up in advance. Maybe an electrician or knowledgable friend could help you there.

You should probably consider how much fuel you will have to store for the generator. I looked into getting one, but decided it was safer and cheaper to get a kerosene heater and store the kerosene. Kerosene is flamable, but not as dangerous as gasoline. Please be careful with the electricity and the fuel.

-- Mike (gartner@execpc.com), September 18, 1998.


Look at your blower motor carfully first. To allow removing the fan & motor for cleaning, mine has a regular plug, rather than being "hard-wired" into the controller. So for my case, I just need a cord available to furnace, and an access to the cord.

DON'T JUST CUT THE CORD.

Check the power is off to the motor, and ALL related sensers and controllers. There are several "feedback" and control wires in there for heater, blower, A/C, thermostat (probably 12 or 24VDC), electronic ignition, etc.), so be sure you know what you're doing, then use a voltmeter to double check everything is dead first.

Else, you will be dead first.

-- Robert A. Cook, P.E. (Kennesaw, GA) (cook.r@csaatl.com), September 18, 1998.


The plug anwer given by Mr Cook WORKS. Where I used to live we routinely had power outages several time per winter. And it seemed they were always when it was 30 or 40 below. Got so the kids knew the drill so well that while mom was lighting the kerosene lanter the kids took thier toy flashlights and puller the gennie out on the porch (starts good when at room temp). All I had to do was take the cord down into the crawl space, unpuug the furnace, and plug it into the cord. If the outage lasted more than about 4 hours (often) we would alternate running the furnace with the fridge and freezer. Whole thing worked so well mom and kids could handle it without self. (Imagine that)

Gary Hale H.M., T.E (See L Frank Baum for references to the degrees.)

-- Gary Hale (garyhale@hotmail.com), September 18, 1998.


One other thing, any time you will be operating a piece of equipment that draws a good chunk of juice, match the length of the cord to the run of the cord.

In other words, a motor 15 feet away from the genset should be hooked to a 15 foot cord. If you cannot buy a premade cord of the correct size, get as close as possible or make your own. And always, always OVERSIZE the guage of said cord, 12-10 guage at the minimum, rather than take the risk of fire.

-- Uncle Deedah (oncebitten@twiceshy.com), September 18, 1998.


Or you could use the proper 'gauge' wire, as the case may be.

-- Uncle Deedah (oncebitten@twiceshy.com), September 18, 1998.


Lest you be gouged by excessive voltage drop....

-- Robert A. Cook, P.E. (Kennesaw, GA) (cook.r@csaatl.com), September 18, 1998.

I find this whole discussion electrifying; blows me away (SOMEBODY STOP ME)

-- John Howard, Greenville, NC (pcdir@prodigy.net), September 18, 1998.

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