Hints for choosing generator for new home Gen Interlock setup

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Had a major electrical re-do of my house, and had the electrician install a generator connection. I believe they are called "generator interlock" systems. It is a standard setup, I can throw a switch in the basement, then plug a generator in outside the house to power the house in event of a power failure.
(save safety warnings.. I know to put generator outside not near door or window, and I can't hook Gen up while still connected to municipal power supply due to lockout system on inside panel, and I know enough to not overload gen)
What should I look for in considering a generator. I am pretty much settled on Honda, as in my experience they are just head an shoulders above all others in reliability and noise. I am prepared to entertain opposing points of view, but I am willing to pay a little more for a good unit.
I don't need super-megawatts.. I will be happy to see that my home has heater, hot water heater (powered venilation unit) and a few lights and maybe a TV. I don't need to run the AC or electric stove.
Could I get away with one of those tiny suitcase type units.. my concern is that they seem to only have standard AC plugs on them, not that special generator circular locking plug that goes into the outside outlet.
Personal experiences or tips? Good online sources for info?
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Jack wrote:

Honda is about the best for noise in the small portable generator category, Yamaha has some units that are pretty comparable. In larger units there are others that are very quiet as well. As for reliability, there are other brands that are very reliable as well.

Heat and HW are gas or oil? Got a well pump that needs power? 5 KW or so will do pretty well for an average house without unusual loads. Refrigerator, lights, TV, a burner on the stove for coffee and furnace and well pump do pretty well with 5 KW. If you do some load management like insuring the furnace and well pump aren't on at the same time you can get by with less.

The real small units are 120V only, a normal transfer switch / interlock really needs a 240V feed. A small unit like a Honda EU2000i would handle a refrigerator and a light plugged into it, but is unlikely to handle a furnace or other larger loads.
Again, the more load management you are willing to do the smaller a generator you can get away with. Nearly all of the typical large household loads are ones that do not require full time power. The refrigerator can readily go an hour without power while the furnace runs for example. The well pump can go without power while you microwave dinner.

Ran a ~1,500 sq ft house with oil heat / HW, well pump, electric stove, microwave, lights, TV, etc. for three days on a Generac 5 KW gas portable generator. Baked stuff in the oven too. Other than the noise and periodic refueling (which I did very carefully while running) it was just fine. Changed the oil after that run.

Perhaps alt.energy.homepower though that leans more towards conservation and renewables. Still most folks off grid with renewable systems have a regular gas generator as backup since renewables aren't 100% reliable, so some expertise there.
Pete C.
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I could have sworn it ran my furnace for 5 days two years ago, as well as my refrigerator and freezer.
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Toller wrote:

It may have depending on what you have for a furnace. In many cases it won't.
Pete C.
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And in many cases it will -- really, the only cases in which it won't are electric furnaces or heat pumps. The electrical demands of oil- or gas-fired forced-air furnaces are quite modest, and those of hot-water systems are even lower. A typical refrigerator requires much more power than a typical gas furnace.
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Seems unlikely, unless the fridge contains a 400 watt blower :-)
Nick
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wrote:

Lets see, my old refrigerator required 23a to start and 3a to run; my furnace is 2a. Seems higher to me, and neither are unusual. (my new fridge is 13/1.5)
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wrote:

Checked a rating plate on a refrigerator lately? I'll bet not.
The one in my kitchen is marked 6.5A. That's a bit more than 400W.
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Yup. Good ones use less than 1 kWh/day.
Nick
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wrote:

You didn't find that on a rating plate. Like I said...
In any event, it's not especially relevant to how much current they draw when they're running, as the total energy consumed is a function not only of motor and compressor efficiency, but also of insulation and usage.
Go check the rating plate on your refrigerator. See how many amps it draws. Now go check the rating plate on your furnace blower and compare.
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snipped-for-privacy@ece.villanova.edu wrote:

That's not a nameplate rating and it's utterly meaningless. The refrigerator could draw 1 KW if it had a total run time of an hour a day.
The defrost cycle on a refrigerator doesn't last long, but it draws a substantial amount of power for the heating element.
Pete C.
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Typically about the same four to five amps, much the same as the compressor.
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Christopher A. Young
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Stormin Mormon wrote:

The point was the KWH/Day is not in any way a measure of actual current draw for anything that doesn't run continuously.
Pete C.
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Refrigerator compressors take a LOT of startup current.
Now days, a typical fridge compressor runs about 4.5 amps running (yes, I'm an appliance repairman, and I get to use an ammeter on refrigerator compressors now and again). Figure another hundred for the fans. Which is generous. But the start up current can be 15 amps or so.
The gas furnaces I've measured tend to run about 7 amps, can't remember the start up currents.
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Doug Miller wrote:

Remember, the EU2000i is rated 1,600VA continuous and 2,000VA for 30 min max. In order to handle many of those furnaces you'd need to do load management so the furnace was the only load at the time.
Pete C.
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Nonsense. 1600VA = 13.3A at 120V. Where have you seen a gas furnace with a blower that pulls thirteen amps? Half that is a little more like it.
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What is it with you? I ran them all for 5 days simultaneously, stopping to put gas in once a day. Thats it; no load management, nothing. And I had spare capacity for a few lights, my computer, or the television. Furnaces just don't use much current.
Had the refrigerator and freezer chosen to start at the same time the generator would have stopped to prevent an overload, but it didn't happen and wasn't likely.
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Toller wrote:

What's with me is I properly size the generator to the load and / or practice load management. I don't rely on fault protective devices to to cover for poor design and management.
Pete C.
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I have a Honda EU2000. It powers my furnace, fridge, freezer, and TV. Not only is it nearly silent, but it gets great mileage. If you have ever tried to buy gas in a major power outage, you will understand that the smallest possible generator is the best generator.
Get an ampmeter and see how much current you need to start/run all the components you want to run. It can vary greatly; my old furnace needed 12a to start, the new one is 2a. Then you have to decide how much you need to run simultaneously; can you live with your furnace and water heater each on half the time? My guess is that the EU3000 will be the best fit, but you have to check things out first.
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Toller wrote:

No, the smallest generator that will handle your load with some safety margin is the best generator. You need to maintain a fuel supply to cover the longest reasonably expected outage.
For the folks in the northeast who heat with oil, a diesel generator is the best since their 275 gal + oil tank will provide weeks of fuel.
You can also store a decent reserve of gasoline if you have a safe place to keep it. Store it in 5 gal cans with Stabil added and rotate them out into your car annually and refill.

A clamp on amp meter with a peak hold function is very useful if you don't mind digging in the breaker panel to use it. For the breaker panel adverse a little meter like the Kill-A-Watt is very useful.
Pete C.
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