Electrical/generator.furnace question?

[Larry Edgerton]

I have a new furnace with all of the electronic controls, and I have a new Yamaha 2200w inverter generator. The two will not play well together. The furnace will go through all of its cycles until it gets up to the time that the burner kicks on and will shut down. The generator is big enough, the same generator runs my old school wood furnace that draws more amps.

So, I stopped by the Yamaha dealer and inquired and they said "Yes we have had this problem with new furnaces, but we do not have a clue." They said a bigger unit will not make a difference, it will do the same thing. Offered no help beyond that.

Anyone have any ideas what is going on and how to solve the problem. Me and electricity are not one.

Thanks, Larry

[Tom Bender]

You may have success with a surge protector but a better way to go is a UPS. This will also carry it thru the few seconds when the power goes out and the generator starts.

I have one for my computer and router, which is handy.

[Nike Nihiser]

Don't want to step on any toes here, but if Larry is not great on electricity he man not know what a UPS is. I think it's an uninterrupted power supply. Sorry, but one of my pet peeves is the use of acronyms that may be less than universally known

[Lee Schierer]

It may be that the output has too much noise in the 60 cycle wave form for the controls. An oscilloscope would show what the output wave form looks like. Based on this video for your generator, it doesn't look very clean.

[Bill Dufour]

Would putting a line/load reactor on the output of the generator help smooth the waveform? Is there someway to separate the motor power from the electronics so a smaller UPC can be used. A UPC to run a motor is going to be big and costly.
Bill D

[Wade Lippman]

I had a Yamaha 2000efi and it was fine with everything, including my furnace with electronic controls. (I remember the installer telling me about all the service calls they have from cheap generators burning out the electronics...).

I think your generator is defective.

[Frank Pratt]

Inverter generators do not put out a true sine wave, more of a squared off blocky facsimile of one. Some electronics don't work well with that. The only work around I can think of is to use a high quality double conversion UPS. They take the line power and convert it to low voltage DC. Some of that power is used to charge & maintain the batteries. The rest goes to a true sine wave inverter that puts out 120V AC that your furnace will like.

The load never actually sees the original supply power & is thus immune to spikes, noise, over & under voltages, and of coarse, crappy sine waves. You need to make sure that the unit puts out a pure sine wave. They are quite expensive.

[Wade Lippman]

Inverter generators do not put out a true sine wave, more of a squared off blocky facsimile of one.

• The Yamaha EF2000iSv2 Inverter generator supplies clean, high quality power. The EF2000iSV2 – with its inverter system – features Pulse Width Modulation (PWM) so voltage stability is within ± 1%, and frequency stability is ± 0.1 HZ. Its pure sine wave is as clean as or cleaner than public utilities power.
• Honda’s Inverter Advantages
  
  Honda inverter technology means stable, clean power in a smaller, lighter package. You can even operate the most sensitive electronics without fear of interruption.
  What’s “Clean Power”?
  
  Computers and power-sensitive equipment require “clean power.” Clean power is electrical current that is consistent and has a stable signal, or sine wave.
  
  
  
  ​I think you are wrong.
  

[Frank Pratt]

• The Yamaha EF2000iSv2 Inverter generator supplies clean, high quality power. The EF2000iSV2 – with its inverter system – features Pulse Width Modulation (PWM) so voltage stability is within ± 1%, and frequency stability is ± 0.1 HZ. Its pure sine wave is as clean as or cleaner than public utilities power.
• Honda’s Inverter Advantages
  
  Honda inverter technology means stable, clean power in a smaller, lighter package. You can even operate the most sensitive electronics without fear of interruption.
  What’s “Clean Power”?
  
  Computers and power-sensitive equipment require “clean power.” Clean power is electrical current that is consistent and has a stable signal, or sine wave.
  
  
  
  ​I think you are wrong.
  

You are absolutely right. I should have qualified that with 'some' The Hondas & Yamahas have a good reputation for having quality inverters.

But Larry's furnace doesn't like something about the power it's getting. It should maybe be checked out by a service tech cause it might just have an inverter problem.

[Art Mann]

Frank, I think you may be confusing inverter generators with the inverters that convert car battery power to pseudo AC power.

[Kev Williams]

Being an RV'er/Boater who's run many a thing using generators and power converters, one way you can test for a 'clean' sine wave is to plug the power supply in question to a microwave oven. A not-so-optimal sine wave will typically make them hum VERY much louder than normal, sometimes scary louder...

[Larry Edgerton]

I will check out UPS's. Should I look at ones the size of the furnace draw or the max output of the generator? I have a Factorymation catalog around here somewhere..........

[Frank Pratt]

Frank, I think you may be confusing inverter generators with the inverters that convert car battery power to pseudo AC power.

No, the technology is the same. It's basically a DC generator that feeds an on board inverter.

I only have (good) experience with a couple of Hondas I own, but I've heard that some of the cheap knock-offs don't deliver the same quality of power. Some of them are less than half the price, so they gotta cut corners somewhere. And good inverters are not cheap.

[Frank Pratt]

Talk to the manufacturers. You don't need the battery backup, but the unit needs to be sized to run your load. I'm not sure, but they may have something that is primarily for power conditioning that would work for you. I would get that generator checked though. A new (not cheap) Yamaha should run that furnace.

[Mike Cutler]

Larry
I would get someone to test your unit with an O-scope. It may just require some adjustment. The Honda's and Yamaha's get really good reviews for their inverter style generators.

As for the UPS,, Maybe, but if you're having trouble with sensitive electronics, you may have a problem with a UPS.
A UPS looks at the quality of the input AC power also, and if it is not within the spec's of the UPS, the UPS will not shift back to line power from battery power, and the UPS will not recharge the batteries. Some are programable for input AC power quality, some are not. You may actually be better off with an AC line filter, bit they're fairly expensive for a large sized model/

As I said, get a tech with an O-Scope to look at the output unloaded, and loaded. You need to know what the problem with the Generator AC output is, to arrive at a solution.