Yamaha EF2400iS Generator

[Bigfoot Mike]

When I owned a 17' Casita I bought a EU2000i Honda generator. It ran flawlessly the whole time I owned it. It ran my microwave, Air Conditioner, etc. with no problems. When I sold my Casita I let the generator go with the trailer.

I then bought much larger Fiberglass trailer a 25' rear queen. So with that larger trailer I decided to research my options. I decided on the Yamaha EF2400iS. It claimed it would run a 13,500 BTU A/C unit and that it was quieter than the Honda. I found one for just a little more than the Honda EU2000i.

It starts easily and runs very quiet.

On my vacation it started and ran great. The problem I had was, it would NOT run my 11,000 BTU A/C unit. Then, it would NOT run my 750 watt microwave. The Yamaha website clearly states it would run both.

So when I got home I took the generator into a Yamaha generator service center here locally. They checked it out, called Yamaha and reported to me the generator is up to specs.

Did I say, when my Yamaha EF24000iS generator would NOT run my microwave or A/C unit, I asked Maggie and West Rudy if we could try their EU2000i Honda. It ran everything with no problem.

So now I am very, VERY disappointed. This is a major set back.

[Curtis F.]

Sorry to hear of your disappointment. If I were closer I'd offer to trade you my Honda 2K for your Yamaha 2.4K.

I have a friend that has a 2.4K and he is thrilled with it. Runs his 13.5K A/C and microwave at the same time. How old is your A/C? Does it have "hard start capacitors"? They can be added to most A/C's. Helps the Generator get over the high amp draw for compressor start up.

How old is your Microwave. What is the amperage spec on the data plate on the back or bottom?

It is strange that the Honda will carry the load and the Yamaha won't.
Have you tried measuring the amperage draw of the A/C and microwave. Measure on house/line power. You could try measuring the amperage draw experienced as each generator was providing power.

Was the Yamaka engine broken in? What type oil is in the generator?

All of the smaller generators will have major problems running older units or units that are not performing optimally.

Curt

[Mike Magee]

I can see why you are disappointed. In fact "disappointed" would be an extremely mild word for what I would be!

I would insist that Yamaha trade me another unit. I have read plenty of positive comments from happy owners who run 15K A/C and stuff off those, so I would think it has to be your particular unit... despite the bull-oney from the service center.

[Bigfoot Mike]

Curtis F., Wow, lots of questions.

The Bigfoot is a 2006. It sat for a year unused before I bought it. The A/C is a 11,000 BTU and the Microwave is a 750 watt.

I would say the Yamaha is NOT really broke in. I have hardly used it. I forget exactly what brand of oil I put into it, but I followed the installation specs.

The overload light came on at 18 amps during several tests. The Yamaha service says it is running up to Yamaha's specs.

So why doesn't it run my 750 watt Microwave, when that is the only thing on, and the Honda EU2000i does?

To me it should be a no brainer for this generator to run what I'm asking of it.

[Darwin Maring]

I once had a Yamaha 1000W and it would start and run the 11,000btu AC and would trip the breaker if the AC cycled off and back on. The Gen was not an Inverter model.

I found it impossible to find someone who would service the unit and extremely hard to get parts. I got rid of it and purchased a McCullough (Kipor by another name) 2000 Inverter model and it worked ok for a while then it started tripping the internal breaker when using the AC. I read the manual again last pm and it states that multiple trips of the breaker can cause it to malfunction. Other than the AC, the McCullough does just fine with everything else. The breaker is not a mechanical one, it is a solid state device and that is more than likely where the problem(s) are.

Bottom line for me: I will stay away from inverter generators. In the future I will get a normal generator and should I require inverter power, I will plug in an inverter to the DC to run any items that require clean AC.

I’m going to purchase a 3000W unit at BJ’S for $199USD and if it is to noisy, I will make a quiet box to put over the unit.

[Bigfoot Mike]

Update...

I went to my local Yamaha Service center to pick up my generator that I took in on a Warranty complaint. The Yamaha service center wanted me to pay $75 for looking at the generator. They told me the generator meets Yamaha's specs.

I took in the Yamaha website printouts claiming the generator would run a 750 watt microwave and "easily" run a 13,500 BTU Air Conditioner (mine is 11,000 BTU). The generator could NOT run either one (and don’t forget the same items run easily with a Honda EU2000i). I asked to speak to the owner of the company. I was told he is unavailable. That is when I became more upset.

So I said, "Do I need to have my attorney help me talk to him?" I continued, "I gotta tell you I have two problems: 1. your printed specs tell me it will run my equipment, which it doesn't and 2. you want to charge me $75 for what I brought in for Warranty work. You tell me it meets specs so it's not your problem."

The service rep said, "I can remove the $75 charge, but you need to take up your issues with Yamaha. We've done all we can do."

I said OK, who do I call at Yamaha? So on it goes... We'll see what Yamaha decides to do.

In the mean time, I am going to get an independent evaluation of the load out put of the unit.

[Curtis F.]

Uhm. Looks like you have covered a lot of the bases. There could be a flaky connection in the trailer that is causing the overload to trip. Another of my friends had a bad power cord that was arcing internally at the plug. Both my honda generators would trip as soon as it was plugged in.

If you didn't buy the generator from the local service center, I kind of understand thier attitude, but I don't approve of it.

Curt

[Bigfoot Mike]

Uhm. Looks like you have covered a lot of the bases. There could be a flaky connection in the trailer that is causing the overload to trip. Another of my friends had a bad power cord that was arcing internally at the plug. Both my honda generators would trip as soon as it was plugged in.

If you didn't buy the generator from the local service center, I kind of understand thier attitude, but I don't approve of it.

Curt

Curtis, if the Honda EU2000i wasn't able to run the Air Conditioner or the Microwave, I would agree it could be something in the trailer. But truthfully, it absolutely had no problem running the appliances. So that brought my focus back on the Yamaha.

When I bought the Yamaha generator from Wise Sales in Indiana, I was told I could take it to any authorized Yamaha Service Center. This Yamaha Dealer signed up with Yamaha to do their Generator Service and is Posted on Yamaha Motors Website.

My past experience with Honda and Kipor generators gave me local service for each even though I bought those also from Internet sources. So putting that all together made me feel confident that a Name Brand Company like Yamaha would also back their Warranties as posted on their website if needed.

[Bruce H]

It seems that this is a problem that can be identified. There has to be a reason for your result. It has got to be one of three things.
1. Something to do with the amp draw of the appliances.
2. A weak breaker or overload switch in the generator.
3. The trailer wiring.
I have the same generator and it starts and runs my 13,500 air conditioner with absolutely no problem. Or it will start and run my Sharpe Carosel convection microwave with no problem. I can't find the wattage of that appliance but it requires a 15 amp breaker.

There was a wiring error in my new Bigfoot in 2004. It cost me $116.79cdn to run it down in the middle of the Canadian wilderness three days after I bought the trailer. They are not above making an error. By the way I took a picture of the improper wiring connection and was still never reimbursed for my expenses under the warranty.

I would try a couple of different things. Test the generator yourself by running it with an extention cord and keep plugging in additional items of known wattage and amp draw until you cause it to trip. One good thing to start with would be an electric bathroom heater. See if you can find an appliance repairman or someone with the testing equipment to check the load draw of the appliances and the output of the generator. Another would be to take the whole rig by a different Yamaha dealer and have them check it out actually attempting to run the air conditioner. I would not mention the previous diagnosis. See if the different mechanic gives you the same answer. Also consider taking it to a Bigfoot or other RV service center for a diagnosis.

You are going to run into alot of inertia trying to force Yamaha to respond via the legal system. I don't recommend even trying it unless you can establish independently there is a defect and file it in small claims court.

[Del Chasteen]

Some thing is wrong somewhere ! I have had my 2400 for two years (heavy usage ) .It will run the AC/micro and all the lights at one time ,no problem .

[Bigfoot Mike]

Thanks guys, that gives me hope. As you both have no problem, I will be really testing my set up to find where the problem is.

The two things that have peaked my interest are:

1. A weak breaker or overload switch in the generator
2. I'm wondering if the Yamaha has a problem with altitude.

When I had the problem I was camping at 9300'. The Honda EU2000i had no problem at that altitude but could the Yamaha? I need to retest now that I'm back at Sea Level.

PS: I am not interested in any sort of legal action. My comment was due to getting stone walled and a lack of willingness of the owner to talk with me. They were not willing to make the generator meet the claimed performance.

[Kurt & Ann K.]

Mike,
I'm reading your experience with interest. Ours has not required service, but should it become necessary...?
In 2003 we purchased a Yamaha EF3000ISE with the expectation that it would run our A/C, microwave, water pump, TV, and lights simultaneously. After having the generator converted to use propane fuel we checked it at 5200 ' altitude and it also ran the Fantastic Fan at the same time. The generator did slow temporarily when the A/C cycled but did not die. Since Yamaha (at the time, at least) was the largest producer of generators in the world I felt fairly confident about their quality. We achieved enough hours of use to need an oil change last fall.
It would appear that something is haywire with your unit. Are motorcycle or outboard dealers actually knowledgeable about generators?

Thanks for sharing,
Kurt & Ann K.

[Bigfoot Mike]

Mike,
...
Are motorcycle or outboard dealers actually knowledgeable about generators?

Thanks for sharing,
Kurt & Ann K.

What I found is that motorcycle or outboard dealers are not knowledgeable about generators just because they sell that type of equipment. On Yamaha’s website they tell you who is qualified to service what. They have an icon system. I actually called the wrong dealer at first and then re looked at their icon system. Then when I called I asked if they were an authorized Yamaha Generator Service Center.

[Darwin Maring]

Test: Turn off all circut breakers except the Air C and see if it will work. This will eliminate all other AC and DC wiring and the converter.

Harbor Freight sells an electric monitor for <$30USD that will tell U the wattage or Amps of the device you have plugged into it.

It plugs into the AC source and you plug the thing U want to test into it and it has a digital readout.

[Bigfoot Mike]

I don’t see any thing like what you are talking about.

electric monitor for wattage or Amps

[Frederick L. Simson]

I don’t see any thing like what you are talking about.

electric monitor for wattage or Amps

Could it be one of these?
Kill-A-Watt

[Bob H]

I don’t see any thing like what you are talking about.

electric monitor for wattage or Amps

Get this Reliance Load Tester...


...I've reccomended getting one here before.

[Pete Dumbleton]

What you might try at the Y dealer for simplicity is to forget mentioning the Honda for now and have them test YOUR generator with YOUR RV and then hook up THEIR similar generator and see what happens. They say it is functioning properly because it meets the tests they have been given, but that may not account for the tests they have NOT be given.

If your generator and their alike generator yield dissimilar results, then they will be hard pressed to ignore the problem. Tell them you will be happy to take home their generator because it works and they should be happy to take home your generator because they think it works -- Har! Ask them if they really want to get involved with lawyers and courts and expensive expert witnesses over something like this.

[Steve L.]

I'm going to offer a phrase with a great deal of tredpidation. It's because it's one of things like string theory physics that I don't fully understand.

The phrase is "Power Factor".

Perhaps one of our electrical engineers can elaborate as I may be way off base.

We know that watts = amps times volts. We know that AC is sinusoidal. Amps are sinusoidal and voltage is sinusoidal. To get the rated watts the volts and amps must peak at the same time. However, frequently they don't phase together. The amount they are different is the phase angle and the sine (or cosine, I don't remember which) of the angle is a factor that reduces the available wattage.

I'm wondering if the Honda has less loss due to phase angle than the Yamaha. Phase angle is why normal clunky generators need to be so much larger than the load they're serving. Better equipment has a higher power factor. A power factor of 1 is best. The closer to one you get the more you pay for it.

I'm uploading a PDF file that explains it. Again, I may be off base.

Note the dicussion on the bottom right of page 46 (no, the file isn't 46 pages long...it's an extract) titled "why won't my generator start my well pump...".

I actually spent some time looking for and eventually bought a clamp on meter that measures power factor. You all bring that trailer and generator over and we'll measure the heck out of it!

[Darwin Maring]

I purchased the Reliance Load Tester from Harbor Freight after Bob H posted it and it works great. I looked through their catalog last pm and could not find it. It was less expensive at Harbor than at Ace.