Looking at propane generators, need some advice

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We are thinking about getting a propane fired generator as we are planning to augment our natural gas heat with propane as our boiler can use both with a minor conversion. We have looked at Generac and Onan. I like the look of the Onan better (just looks better built) but most of the web advice seems to steer longer term generator users toward 1800 rpm (diesel) versus 3600 rpm generators. We plan on running whatever we get for a few hours in the morning and the evening to keep the house warm enough to prevent it from freezing solid and to get hot water (if city water doesn't poop out on us) but that's about it. Any practical experience and advice regarding a 2500 to 3500 watt propane generator would be appreciated. BTW, I did research the archives before asking this question to potentially avoid wasting everyone's time.

-- Ramp Rat (Aviation_R_us@noname.nocity), March 21, 1999


Usually the lower the rpm the better. The speed reduction translates into longer life. I also prefer Onan's. You might also look at the spare parts situation.

-- nine (nine_fingers@hotmail.com), March 21, 1999.

5000w gas [propane] generators [generally] 3600 rpm- 4 pole brush type.1/2000 hrs before overhaul, $5/900. diesel generator [generally] 1800 rpm 4 pole induction [no brushes] 30000/40000 hr before overhaul cost $5000/15000.

-- bob crozier (rcrozier@koyote.com), March 21, 1999.

Onan propane generators are excellent. They burn clean with little maintenance and propane does not corrupt in storage like liquid fuels.

I know. I have owned two over many years and would buy another if needed. Just watch, top up and change the oil methodically. Get extra spark plugs that you will seldom need.

Do not buy more KW's than you really need. Scale down your uses. Charge a couple of extra batteries while in AC use for DC radios, pumps, lights etc.

Best wishes,

-- Watchful (seethesea@msn.com), March 21, 1999.

Your choice is dependant on your needs. If you are purchasing the generator strictly for Y2K then you only need to purchase a unit whose duability will last as long as the amount of fuel that you intend to stock.

Since you are going for a low power (less than 20kw) you can use gaseous rather than liquid propane (normal feed rather than the more complex and hazardous lower tank feed).

You can find Winco and other brands that sell high quality multiple cylinder propane/nat. gas units. 1800 rpm units require 4 pole generators whereas 3600 rpm can use cheaper 2 pole units. Most engines produce more horsepower at 3600 rpm than at 1800 rpm so for a given max. wattage the 1800 rpm will be a larger engine. If you are only going to be running the unit 4 hours per day, that's 1,400 hours for one year. However, since you are only interested in preventing freezing the question is how long do you think Y2K will keep the electricity off and how many freezing days will you have to run the unit?

I would suggest that you get a dual fuel (propane/nat.gas) since it is possible that you might have nat. gas longer than electricity, thereby extending your propane supply a bit.

On size of generator, please remeber that electric motors require two to four times as much power to start than they do to run. Generators are usually rated (high to low) by; peak power (motor starting), continuous standby power, and continuous prime power. Since you are running your heating system for short periods, you just need to worry about motor starting ability.

The atraction of diesel is the durability of the engine since they have to be built like a brick to withstand the high compression ratio required to diesel and the ease of fuel storage. Diesel fuel stores very well with added anti-oxidents and anti-fungals in cheap containers, 55 gallon barrels at $20 each. While diesel is flamable, it is not explosive like gasoline fumes, propane, or nat. gas. You can purchase dyed off-road diesel for generators and avoid the road tax. Their are small diesel gensets made, but this would be adding a fourth fuel to your life (nat.gas, gasoline, propane).

-- Ken Seger (kenseger@earthlink.net), March 21, 1999.

I noticed you said something about running the generator for hot water. Electric water heater??

Not so good an idea. Get a demand propane heater -- if possible one that needs no electricity (I say that knowing that I'll have to replace my electric water heater, too -- 7000 watts when heating).

-- Dean -- from (almost) Duh Moines (dtmiller@nevia.net), March 21, 1999.

Negative on the electric hot water heater. Our water heater is a "boiler mate", all hot water is heated from a boiler loop (a separate zone on the boiler). If the boiler/furnace runs, the hot water is free for the taking. Best thing since sliced bread. No need to augment our hot water system as long as the boiler runs. That's why we only need 2500-3000 or so watts a few hours morning and evening. Keep the boiler pump and heaters running a few hours, a couple of times a day to keep house from freezing (the house is well insulated with state of the art "super" insulated windows in the improved areas, 75%) and to (incidently) heat up water for showers and clean up presuming we have safe running water and the sewage system is working. We have plan B for water and sewer as well if that falls down. If we can just get over the heat hurdle we will be fine as we are set with food and water and an emergency room doctor lives across the street from us.

-- Ramp Rat (Aviation_R_us@noname.nocity), March 21, 1999.

Hello Ramp Rat,

I have a 4kw Onan "Emerald" generator modified to use propane. It's an excellent unit, and I would recommend it without hesitation.

When I picked it up, I asked to keep the gas carb so I could retrofit it if necessary back to unleaded. This gives me even more flexibility if TSHTF. I have some stored gasoline as well as propane.

Jolly has the power.

-- jollyprez (jolly@prez.com), March 21, 1999.

Ramp Rat: You might want to take a look at the various generators offered at this website: http://www.gohonda.com. They are the only source I've found for the new Honda dual-fuel (gasoline/propane) engines, which allow the user to change fuels without making any carburetor adjustments. I've had better luck with Honda engines than with any of the other small engines such as Briggs and Stratton, Tecumseh, etc.; and my wife finds them easier to operate, as well. I asked several local generator distributors to check out the specs on these units, and they all said that they couldn't match them feature-for-feature. Lots of interesting specs, such as brushless, ball-bearing Hercules generators, electric starting, +/- 5% voltage regulation, 100% power factor, etc. I selected the LV70E-Z unit as best meeting my needs. A word of caution: they will guarantee y2k delivery only if you order by 1 April. They also get a 52% break on shipping from Yellow Freight. (The name of the company is: Discount Air Compressor and Generator Co. of Pontiac MI; I don't have any connection with them other than having ordered one of their units.)

-- Norm Harrold (nharrold@tymewyse.com), March 22, 1999.

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