? On quiet generators and size needed for TT ac

HuckleberryHunter wrote:
I knew a 2000 watt unit was going to be a bit small for our single AC unit, so wanted something a bit bigger and a lot quieter.

Not necessarily true. I've owned two different Honda EU2000i gensets and either would successfully and repeatedly start the 13,500 BTU Coleman Mach 3+ and Dometic Brisk II A/Cs I've owned BUT at around sea level and in temps up to the mid 80s. Increase the elevation and/or ambient temp and the genset would overload. However, that was before I knew about the Micro-Air Easy Start Soft Starter Kit but had it been available at that time I would have definitely invested in one. Also, the Honda EU2000i which features by far the best surge capability of any 2K genset has been replaced by the even more capable EU2200i which has a much larger 121 cc engine. Chances are that a combination of an Easy Start and an EU2200i could quite well start a 13,500 BTU A/C at higher elevations & much higher ambient temperatures and keep it running. :B

After 1 year on a contractor style (open frame) hand-me-down generator we bit the bullet and sprung for a Honda eu3000is. That contractor generator was just too loud!
I knew a 2000 watt unit was going to be a bit small for our single AC unit, so wanted something a bit bigger and a lot quieter. We've not had any regrets since. Granted, it's bigger and heavier than the suitcase style generators, but ease of use and peace of mind have been worth it to us. I put it on a dolly when at home to move around and my wife and I can lift it together and move it if necessary at the campsite, but usually it stays int he back of the truck and I run it there. It's also come in handy as an emergency home generator during years when we have the occasional power outage.
Recently I've considered the idea of getting two of the Honda 2000 and use one for times when the AC isn't needed and pigtail the two for 4000 watts when the AC is needed, but am in no hurry to do that as the eu3000is is still going strong. It would be nice to be able to store them in the TT hold though, which I think I could do with the 2000.

PS - Honda and Yamaha used to rule the market, but in recent years there have been a lot more of the quieter inverter style generators being produced by other manufactures. A friend of mine just got a 4k unit from Costco that reportedly produces something like 62 decibels and was considerably cheaper. It's not as quiet as our Honda, but still better than than the previous alternative. And, you can still hear the Honda if you're in the next campsite over, not loud, but audible. I have yet to hear his generator run, but at some point this summer I plan to hear how it compares.

luberhill wrote:
Ok I saw the easy start video, so it sounds like a 2.k watt invertor Honda will in fact run the ac,,, is there any downside to using the easy start ?why don’t the manufacturers just put them in to start with ?

$$$$$$$$$$$$$

valhalla360 wrote:
There is a partial solution. They can add a "soft start" unit to the air/con. This is basically a small capacitor that stores up some power and when the compressor kicks on, the capacitor dumps it's power into the system and makes up much of the difference...2000w is still marginal.

The MicroAir EasyStart is not a "soft start" capacitor. It is something entirely different, and works MUCH better than any "soft start" capacitor. Do a search in RV.NET on "MicroAir EasyStart" and you will find thread after thread from people who have actually installed them on their rigs.

A single 2000w generator is marginal.
- First that's a peak output rating not continuous. Continuous is typically around 1600w.

To run an air/con you need to consider both the startup power and continuous power demand. Continous for a typical air/con unit is going to be around 9-12 amps (or 1200-1400w). Sounds good that is below 1600w rating but to get the compressor turning, you need a surge of extra power...typically 2-3 times as high...that's way beyond what a 2000w generator can do.

There is a partial solution. They can add a "soft start" unit to the air/con. This is basically a small capacitor that stores up some power and when the compressor kicks on, the capacitor dumps it's power into the system and makes up much of the difference...2000w is still marginal.

As mentioned by others, traditional generators have to run at constant speed so that the hertz stays correct. High speed operation tends to be noisy. Inverters take DC power and electronically invert it to create AC power. This allows the motor to be throttled to match the demand. This allows the generator to be more efficient and to be quieter.

There is a catch with the quieter. If you are running the air/con, the generator is going to throttle up for the higher load. Under light loads, the generator may just be a soft hum but when putting out full power, it's not nearly as quiet.

2000w generators are popular because they are easy to carry around. To mitigate the limitation, some manufacturers have designed them so you can link 2 together (Don't try to DIY connect two generators, its more complicated than it sounds and you can cause a lot of damage). Of course, this is an expensive solution.

We have a 2400w Yamaha that does fine for a single air/con (plus a few minor loads). It's probably at the low end of what I would consider. If I was buying a new one, I would probably bump up to 3000w.

RTCastillo wrote:
Get 4,000 watts to run the a/c reliable, the ref and turn on the microwave from time to time.

IMHO, that is overkill !

3,000W - 3,500W will run most A/C units and a microwave, assuming they do not START at the same time. Stick with an inverter generator.

Rigs with TWO A/C units usually have a 240V/50A power cord. You need a generator that makes 240V. Very few inverter generators make 240V.

luberhill wrote:
Do do you need an invertor type ?? Also isn’t a 4000 watt a little large to carry around ?? These guys camping here say they don’t need the ac because it doesn’t get that hot

I recently spent 20 days camping (10 in May, 10 in July). We had many days where temps got well above 85*F. It was nice to run the A/C off my 3500W Predator inverter generator. The generator ran very quite with a noise level around 50-52db @ 30'. My A/C was drawing about 17 amps.

The inverter types are usually quieter than open frame types and more compact / smaller. My HF Predator 3500W is much quieter than my Champion Dual Fuel 4750W which runs about 65-67db @ 30'.

Both are heavy IMO. The Predator as small as it is weighs 117# with a full tank and the Champ weighs about 134#. Those weights weren't a problem in my younger days but not something I want to lift in or out of the truck by myself today.

Let's go over the fundamentals, and I think that will answer most of your questions.

An ordinary generator consists of a small gas engine direct coupled (no belt or chain drive) to an alternator that puts out ac current. In order for it to put out 120 volts, and more importantly, 60 cycle electricity, it needs to run at a fixed speed, usually 3600 rpm. If the rpms on the genny fluctuates, so will the voltage and the cycles - you might get 105 volts at 57 cycles, or something like that.

Since it has to run at the same speed regardless of the electrical load on it, this would be the same as if your car had to run at 4000 rpm whether it's going 10 mph or 70 mph.

Now, an inverter generator starts out with the same small engine and alternator, but the output of the alternator goes through a bank of diodes to convert it to dc, just like the alternator on your car. A built in inverter takes that dc and changes it back to ac current.

Since the inverter is creating 60 cycle 120 volt ac from the genny's output, the genny no longer needs to race along at 3600 rpm at all times, it can throttle back to low rpm when the electrical load is low. This is why the inverter generator runs quieter, and why it runs longer on a tank of gas. Even though it costs more to add the diodes and inverter to the generator, it will more than pay for itself in fuel savings over it's lifetime.

Now, a few other bits of information

A 2000 watt generator is not capable of putting out 2000 watts CONTINUOUSLY. Usually it's good for 1600 watts continuous, with brief periods of up to 2000 watts to start loads like air conditioners and refrigerators, where the starting load is higher than the running load.

All generators are rated at sea level. As you go up in elevation, all gas engines lose power, including the ones on your genny. A genny that might be capable of running your A/C in Florida might not be capable of running it at 10,000 feet in Colorado.

With Honda, and Yamaha generators, and, I guess Champion and some of the others I'm not that familiar with, you can hook a sync cord between two of them and pull double the output out of the pair via a single power cord. In other words, two 2000 watt gennies synced together turn into a 4000 watt generator. It costs more money to do it that way, but it's easier to handle and move the two separate units than it is to handle or move a much heavier 4000 watt generator.

Finally, Honda is the only one I know of that uses a fuel pump. The rest, AFAIK, all use gravity feed. With the Honda's, you can get kits that let you draw your fuel from a much bigger fuel container. I've seen adapters for 5 gallon jerry cans that let you convert them into fuel tanks for the Honda. With a setup like that, you could easily let the generator run all night while it provides power for an electric heater you are running in you rv to keep it warm.

BTW, Honda has just discontinued their 2000 watt gennies and replaced them with a 2200 watt model.

Hope this answers your questions.

RTCastillo wrote:

luberhill wrote:
Do do you need an invertor type ?? Also isn’t a 4000 watt a little large to carry around ?? These guys camping here say they don’t need the ac because it doesn’t get that hot

We have ours mounted but weight is not really a big issue as me and my wife can lift it had we need to take it in and out of the trailer to run it.

Quiet is also not a big issue since campgrounds have rules to shut off all generators either 7 through 10 every night anyways.

I don't know about not needing a/c but had your trailer been in a treeless or not parked on a shade, you will definitely need one should you want to rest inside during the day and even nights.

Rules or no rules if others are around quiet is a huge issue. No one wants to listen to a loud obnoxious open frame geeny when much quieter inverter models are available

luberhill wrote:
What’s a “genny” is that slang for ac ?? Sorry im confused.. im aware of campground rules, thinking of it when boomdocking...and again what size would I need to run ac and which isnquieyest

Genny is slang for generator.

Camping in a campground with no hookups, is Dry Camping, not Boondocking. Boondocking is camping in non-developed areas, like the desert, national forest or auto races. In the Boonies.

If you are going to use a generator in a campground, you need an inverter generator, because they usually are much quieter than open-frame contractor-style generators.

luberhill wrote:
Ok I saw the easy start video, so it sounds like a 2.k watt invertor Honda will in fact run the ac,,, is there any downside to using the easy start ?why don’t the manufacturers just put them in to start with ?

If you only need 2,000, Honda generator is the best of 'em. Honda is topnotch in small engines.