15,000 BTU A/C, EasyStart, What Generator?

[wulfraat]

Originally Posted by Landrum

Well.....I'd like to know what you've learned about propane converted generators. I just ordered a Honda eu2000i from Genconnex and was planning to install an EasyStart in our 15,000 BTU AC. Do you happen to know if that combo will work? Thanks

I have that same setup. Works for me.

[Micro-Air]

Originally Posted by Landrum

Well.....I'd like to know what you've learned about propane converted generators. I just ordered a Honda eu2000i from Genconnex and was planning to install an EasyStart in our 15,000 BTU AC. Do you happen to know if that combo will work? Thanks

Landrum - Almost all of the customer with Honda EU2000i generators running on propane that had no problem running their A/C with EasyStart had the Genconnex conversion kit. In all cases, unless these customers were above 3000', their Honda generators could deliver 2000W steady-state and indefinitely. You should therefore be fine with yours. There have been a few scattered cases with US Carb conversions as well, but nothing I can confirm like I can with Genconnex. Most recently, I handled a case with a customer who had the Hutch Mountain propane conversion. He had issues running his A/C on the generator, and I talked him through conducting a separate load test (without the A/C) using a clamp-on ammeter and a special cheater cord to give him access to one of the hot conductors. He found that when running on propane, the generator couldn't even deliver 1600W, let alone the 2000W we're all spoiled by with the Honda EU2000i. Given most 15kBTU A/Cs require at least 1800W on a moderately hot day, the generator needs to deliver its full capacity.

Originally Posted by AstroBruce

Matteo, I have no problem with MicroAir or the 2 EasyStarts I installed on my AC units. They do the job they were designed to do, and do it well. That is to ease the starting load. My problem, as you know, is the Honda 2000s can't carry the load at higher ambient temperatures. Has nothing to do with EasyStart. The generators have a US Carb conversion with an adjustable load block. I can adjust the mixture with the turn of a screw.
My generators are at borderline max output running the AC. I get that. If you come up with some kind of fix, I'm all ears.
Thank you for all the help you have given me online and off. I learned a lot. The EasyStarts are staying right where they are. Great piece of gear. I'll keep monitoring these threads. Bruce

Bruce - Thanks for your faith and support, and thanks for specifying the conversion. As I mentioned above to Landrum, we have less experience with the US Carb propane conversion. Perhaps there is an adjustment on those that might help you? Wulfraat chimed in as he and I worked quite extensively on his case which involved rejetting for gasoline because he was at very high altitudes, but I don't recall his having a propane conversion. (I'm sure he'll correct me if my memory is fading!)

[wulfraat]

Bruce - Thanks for your faith and support, and thanks for specifying the conversion. As I mentioned above to Landrum, we have less experience with the US Carb propane conversion. Perhaps there is an adjustment on those that might help you? Wulfraat chimed in as he and I worked quite extensively on his case which involved rejetting for gasoline because he was at very high altitudes, but I don't recall his having a propane conversion. (I'm sure he'll correct me if my memory is fading!)

Matteo - I recently upgraded to propane this summer when I got my new trailer. Got tired of dealing with gas fumes while transporting the genset.....

[Micro-Air]

Originally Posted by wulfraat

Matteo - I recently upgraded to propane this summer when I got my new trailer. Got tired of dealing with gas fumes while transporting the genset.....

Thanks, Wulfraat. I'm glad to read my memory still serves correctly! Your propane conversion kit is US Carb I presume, based upon what you wrote earlier?

[kscherzi]

A little update on the Yamaha 2000 yesterday. It was close to 100 degrees according to the camp host and at 1200 foot elevation. The generator could only start and run the AC when eco mode was off. Further the generator kept going into overload about every 15 or 20 minutes. So I had to stop then restart it to get the AC going again.

Earlier this year I ran a test where the Yamaha 2000 ran for about an hour, but it was cooler, probably mid 70's.

Bottom line it worked, but a hassle to keep restarting the generator every 15 or 20 minutes. Also, the little generator ran like mad to keep up. Not sure how long it will last like this.

[Micro-Air]

Originally Posted by kscherzi

A little update on the Yamaha 2000 yesterday. It was close to 100 degrees according to the camp host and at 1200 foot elevation. The generator could only start and run the AC when eco mode was off. Further the generator kept going into overload about every 15 or 20 minutes. So I had to stop then restart it to get the AC going again.

Earlier this year I ran a test where the Yamaha 2000 ran for about an hour, but it was cooler, probably mid 70's.

Bottom line it worked, but a hassle to keep restarting the generator every 15 or 20 minutes. Also, the little generator ran like mad to keep up. Not sure how long it will last like this.

Kscherzi - Your generator is the original Yamaha EF2000iS and not the newer EF2000iSv2, correct? I recall our discussion about this in another thread where the difference between these two generator "generations" was discovered by us all.

[kscherzi]

Originally Posted by Micro-Air

Kscherzi - Your generator is the original Yamaha EF2000iS and not the newer EF2000iSv2, correct? I recall our discussion about this in another thread where the difference between these two generator "generations" was discovered by us all.

The Yamaha I have is the newer V2 version. I do have the 15,000 BTU Dometic AC that Airstream has been installing the last few years.

The issue is probably that the current draw exceeds the Yamaha's ability to maintain over time. I think the V2 version will operate at a higher output for a while then eventually gives in to overload. Not sure where that line is crossed but it seems to be after 15 or 20 minutes.

[wulfraat]

Originally Posted by Micro-Air

Thanks, Wulfraat. I'm glad to read my memory still serves correctly! Your propane conversion kit is US Carb I presume, based upon what you wrote earlier?

I used the GenConneX conversion.

[guskmg]

Contact US Carburetion. They will tell you there is no derating on propane with their Snorkle System. The simple fact is it just takes more fuel volume to get the same BTUs. I have had their equipment for ten years and notice no power losses on propane.
guskmg

[guskmg]

One other item of info: just like engines without turbos, as the temperature rises or the pressure decreases or both, volumetric efficiency decreases and therefore, power loss occurs. You can determine this effect using a Koch Chart. This can occur at Sea Level if either condition changes from a standard day (68 degrees and 29.92 hg).
guskmg

[Trailbob]

We have the 15K Penguin II in our AS. I installed the Easy Start 364 in early July. We have two Honda eu2000i generators; one is gas, the other has the US carb conversion and can run on either propane or gas. I did the 5 AC starts on shore power and it worked fine. I was unable to start the AC on the propane generator. I could start the AC on the either the gas generator or the dual fuel generator running on gas, but after about 8 minutes, the voltage would drop and AC compressor would shut off. There were no other loads on in the trailer (resting amps were about .4)

I had several e-mail exchanges with Matteo. He was prompt and helpful in his replies. One of the things he suggested was cleaning the condenser fins and fan blades on the AC.

I spent a couple of days (on and off) trying different ways to make the AC work. I made sure the generators were functioning properly (clean air filters, fresh high octane non-ethanol gas in both of them), cleaned the AC unit, etc.

I took various measurements of voltage and amp draws on 20 and 30 amp shore power, as well as the generators. I determined that at 95 deg, on 20 amp shore power, our AC draws 15.9 amps at 115v, or 1829 watts. When I ran the same tests on 30 amp shore power, or the gas powered generators (while the AC ran) the wattage use was similar.

I live near Boise, at about 2500' elevation. An on-line manual for the Honda eu2000i states that the carburetor should be re-jetted if the generator is consistently operated above 5000' (on gasoline), and that the power drops about 3.5% for every 1000' of elevation gain.

"Even with carburetor modification, engine horsepower will decrease about 3.5% for each 1,000-foot (300-meter) increase in altitude. The effect of altitude on horsepower will be greater than this if no carburetor modification is made."

At 2500' elevation, I believe this would be an 8.75% reduction in available watts meaning that my 2000 watt generator can put out 1825 watts (max). The (Honda) recommended sustained output would be even less. This leads me to conclude that I am asking too much for a single Honda eu2000i to reliably operate our trailer's AC unit in our area, since it draws around 1829 watts.

I followed the Easy Start threads for a long time before deciding to put one in our trailer. I have read where many people have successfully run their 15K AC units on single Honda or Yamaha 2000w generators, some at higher elevations than I live. But it didn't work for me with a single 2000w generator at the elevation (and temperatures) where I need it.

I don't fault the Easy Start product, it works as advertised and allows the generator to start the AC. I also don't regret putting the Easy Start in, since it does start easier on a 20A shore power circuit, and it may work fine if I camp at lower elevations. But if I were shopping for a single generator to reliably run our AC where we camp, it would be something bigger than the eu2000i.

[GCinSC2]

Trailbob,

Just a thumbs up for data and presentation. I even sorta followed it.

A challenging topic. I'm still learning and this weekend might try my Honda 3000 again after replacing caps on my penguin 15000.

Gary

[wulfraat]

Originally Posted by Trailbob

We have the 15K Penguin II in our AS. I installed the Easy Start 364 in early July. We have two Honda eu2000i generators; one is gas, the other has the US carb conversion and can run on either propane or gas. I did the 5 AC starts on shore power and it worked fine. I was unable to start the AC on the propane generator. I could start the AC on the either the gas generator or the dual fuel generator running on gas, but after about 8 minutes, the voltage would drop and AC compressor would shut off. There were no other loads on in the trailer (resting amps were about .4)



I had several e-mail exchanges with Matteo. He was prompt and helpful in his replies. One of the things he suggested was cleaning the condenser fins and fan blades on the AC.



I spent a couple of days (on and off) trying different ways to make the AC work. I made sure the generators were functioning properly (clean air filters, fresh high octane non-ethanol gas in both of them), cleaned the AC unit, etc.



I took various measurements of voltage and amp draws on 20 and 30 amp shore power, as well as the generators. I determined that at 95 deg, on 20 amp shore power, our AC draws 15.9 amps at 115v, or 1829 watts. When I ran the same tests on 30 amp shore power, or the gas powered generators (while the AC ran) the wattage use was similar.



I live near Boise, at about 2500' elevation. An on-line manual for the Honda eu2000i states that the carburetor should be re-jetted if the generator is consistently operated above 5000' (on gasoline), and that the power drops about 3.5% for every 1000' of elevation gain.



"Even with carburetor modification, engine horsepower will decrease about 3.5% for each 1,000-foot (300-meter) increase in altitude. The effect of altitude on horsepower will be greater than this if no carburetor modification is made."



At 2500' elevation, I believe this would be an 8.75% reduction in available watts meaning that my 2000 watt generator can put out 1825 watts (max). The (Honda) recommended sustained output would be even less. This leads me to conclude that I am asking too much for a single Honda eu2000i to reliably operate our trailer's AC unit in our area, since it draws around 1829 watts.



I followed the Easy Start threads for a long time before deciding to put one in our trailer. I have read where many people have successfully run their 15K AC units on single Honda or Yamaha 2000w generators, some at higher elevations than I live. But it didn't work for me with a single 2000w generator at the elevation (and temperatures) where I need it.



I don't fault the Easy Start product, it works as advertised and allows the generator to start the AC. I also don't regret putting the Easy Start in, since it does start easier on a 20A shore power circuit, and it may work fine if I camp at lower elevations. But if I were shopping for a single generator to reliably run our AC where we camp, it would be something bigger than the eu2000i.

Just curious if you are running the AC fan in "auto" mode or low / med / high?

It will default to a high fan speed, you may try forcing the AC to run the fan at "low" speed. Should save 0.5-1 amps.

Also - I assume your fridge is on LP, and batteries are disconnected from the charger...

Sad to hear its not working out

[Trailbob]

Originally Posted by wulfraat

Just curious if you are running the AC fan in "auto" mode or low / med / high?

It will default to a high fan speed, you may try forcing the AC to run the fan at "low" speed. Should save 0.5-1 amps.

Also - I assume your fridge is on LP, and batteries are disconnected from the charger...

Sad to hear its not working out

I set the AC fan on low (based on what I read in previous threads). The batteries were at 100%, and the fridge (and everything else) turned off. The trailer's amp draw before the AC kicked on was only 0.4 amps.

[Micro-Air]

Originally Posted by wulfraat

Just curious if you are running the AC fan in "auto" mode or low / med / high? It will default to a high fan speed, you may try forcing the AC to run the fan at "low" speed. Should save 0.5-1 amps. Also - I assume your fridge is on LP, and batteries are disconnected from the charger...Sad to hear its not working out

Originally Posted by Trailbob

I set the AC fan on low (based on what I read in previous threads). The batteries were at 100%, and the fridge (and everything else) turned off. The trailer's amp draw before the AC kicked on was only 0.4 amps.

Great report and test orchestration, TrailBob, and I recall our previous conversations. Spot on question, Wulfraat, and TrailBob's response indicates he did everything correctly by eliminating all auxiliary loads AND confirming the exact amount of power/current being delivered before the A/C came on. I think I see the problem here that is being missed. At the risk of hijack, I'm going to share with you some of my recent learning, which does apply.

This battle with unexplained reduced steady-state performance with the Honda EU2000i under various conditions - altitude, propane operation, maintenance, age, etc - has varied in the customer cases I've worked on over the past year. Fortunately, the number of customers affected is low, probably less than 2%. I've been battling a 10-year-old Honda EU2000i myself since mid-May that has an almost identical problem (the analysis testing and engine teardown for which I'm logging in a power equipment forum). I have learned a MASSIVE amount about the Honda EU2000i because of this investigation, the most important of which pertains to one of TrailBob's calculations and conclusions.

At 2500' elevation, I agree with TrailBob's engine power reduction estimate of 8.75%, without rejetting. However, this does not correspond one-to-one with a loss in the generator's power output capability. The reason is because at sea level on gasoline, the Honda's engine has excess power to maintain the critical 5000RPM that is required to output its full capacity of 2000W (16.7A @ 120VAC). Realize that the throttle control system for the Honda uses output voltage and current to determine what to do with the throttle setting. There is a great chart in the service manual attached below.

Barring any issues with the rotor magnets, stator windings, and inverter section (all of which I have come to learn are extremely rare and will exhibit different symptoms), if the Honda's engine can maintain close to 5000RPM under full load (per the chart), then the generator's output will in fact be 2000W, or 16.7A somewhere between 110 and 120V. Since TrailBob's generator can output the required capacity for 8 minutes, like I already proved on my Honda by conducting the outlined stator and rotor output tests, I predict that those are already eliminated as possible causes for him. The real cause is with the engine not being able to maintain the control system's "requested" RPM.

I've closely analyzed the throttle operation of a new "working" Honda versus the one I have that has a problem similar to TrailBob's. With the maximum load applied, a Honda in good working order will only be about 90% throttle to maintain 5000RPM and full output capacity. As you raise the altitude, reduce the energy density of the fuel (i.e. use propane), or suffer some sort of other engine issue (e.g. fuel delivery, air delivery, spark problem, compression, etc.), the amount of throttle required to maintain the target RPM increases. Once the throttle hits the wide-open stop, the RPM of course will begin to drop away from what the chart is calls for. As the RPM drops, so does the output voltage and therefore output current capacity for a given load device. Once the voltage drops below 85VAC, most rooftop A/C compressors will stall. The EasyStart catches this, and immediately shuts down the compressor as part of its fault detection/protection. The generator then immediately becomes unloaded, the RPM surges, the throttle cuts back, and then it stabilizes again.

In TrailBob's case, given what other customer's have reported and attained at even higher altitudes, I believe a Honda EU2000i in proper working order, operating on gasoline, should be able to attain its maximum power output capability (2000W) at 2500' elevation. Therefore, I contend that TrailBob's Honda EU2000i has something wrong with it and its performance limitation is not normal.

Now comes the question on how to diagnose and fix it! I won't claim to be a small engine expert, but over the past 3-1/2 months, bringing my engineering skills to bear, doing an enormous amount of research and case study reading, and doing the detailed analysis, testing, and engine teardown of the Honda EU2000i I'm working on, the following are the diagnostic and troubleshooting steps you must carry out to get to the bottom of this problem:

1. Beyond your voltmeter and ammeter, which are critical tools, you need to get one of those little add-on RPM/Hour meters specifically meant for the Honda EU2000i. They are avaiable for around $35. Knowing the RPM is critical.
2. Study the throttle mechanics and learn where the full throttle stop is and what its position will look like. Then, observe the RPM and throttle position during the first 8 minutes of "good" operation. I'll bet you that the RPM will be maintained somewhere between 4700 and 5000RPM (depending on how much current your A/C is drawing that day). Then, over the next few minutes, the throttle will slowly open until it reaches its wide-open stop, then the RPM will start dropping, along with the output voltage. Compressor motors (inductive loads) behave a little bit differently than resistive loads in the face of reduced voltage. Initially they might maintain or even increase in current as the applied voltage drops off, but they will eventually start decreasing in current with decreasing voltage. (Purely resistive loads will always decrease in current with decreasing voltage, per Ohm's Law.)
   
3. Observe how far the voltage output has to drop before the compressor finally stalls. The voltage decay starts slowly, but then occurs rapidly once you get below 100VAC.
   
4. Eliminate possible engine causes in this order of likelihood:
   a) Fuel delivery - carburetor issues, fuel filter, fuel pump. These are the most difficult and time consuming. Carburetor cleaning is always tough since you can never be 100% certain you found and cleared every tiny hole or port. Over the past 3-1/2 months I've purchased brand new replacements for all 3 in order to safely eliminate then.
   b) Spark - spark plug and ignition module - The spark plug is easy and cheap to replace. The ignition modules almost never fail, or exhibit degradation after 8 minutes of operation, so you can safely eliminate it.
   c) Air - air filter and carburetor gaskets - easy to check and not often a cause anyway.
   d) Compression - piston rings and valve seat interfaces - where I am at now on my generator. More on that in the other forum.

Sorry for the long post here, but I wanted to share with everyone what I have learned so far. I just received the new set of rings for my Honda, and will hopefully be doing the reassembly over this long holiday weekend. I'll let everyone know my results.

[pteck]

That was an awesome post. I know more about my little honda in that 1 post, then I have gleaned just about everywhere else. Time to hit the pool as I've done my learning for today.

[Trailbob]

Originally Posted by Micro-Air

In TrailBob's case, given what other customer's have reported and attained at even higher altitudes, I believe a Honda EU2000i in proper working order, operating on gasoline, should be able to attain its maximum power output capability (2000W) at 2500' elevation. Therefore, I contend that TrailBob's Honda EU2000i has something wrong with it and its performance limitation is not normal.

Thanks Matteo for the very informative post. It is obvious you have put a lot of effort in learning the inner workings of these generators.

I wanted to clarify that I ran my tests with two separate Honda eu2000i generators, one on gasoline, the other on propane and then on gasoline. Neither generator, running on fresh premium gasoline, could continue operating the AC.

I am going to try and borrow a Yamaha or Honda 2000w generator and will report back if I run additional tests.

[Micro-Air]

Originally Posted by Trailbob

Neither generator, running on fresh premium gasoline, could continue operating the AC.

Trailbob - Thanks for the clarification that you were using 2 different generators with two different fuels. Ignoring the propane test for the moment, I've read in more than one place that using high octane fuel at higher altitudes is the opposite of what you want. This is because at higher altitudes, the compression is reduced due to the thinner air. Higher octane fuels are designed to burn slower for higher compression engines. Lower octane works better in a lower compression engine or environment. Wulfraat and I dug into all of this way back when we were battling his challenges above 5000'. Another way to look at it is the engine inherently runs richer due to thinner air. Contrary to what might seem intuitive, rejetting the Honda with either the 60 or 58 main jets causes the mixture to become leaner, which is needed at higher altitudes. Beyond all of this, Honda recommends regular unleaded gasoline (87 octane) for the EU2000i under normal conditions anyway.

I might therefore recommend using regular unleaded fuel for your testing.

Quick update on my Honda EU2000i rebuild project - the new piston rings did not help. I was most disappointed since a complete engine teardown and carbon cleanout required quite the effort. After an evening of sorrow and further analysis of what I observed while the engine was apart, I have a new theory. I've ordered parts and will try again. The only good news is I can probably disassemble the Honda EU2000i blindfolded now, in record time!

[pteck]

Matteo, sorry to hear your engine refresh with new piston rings did not help. I suspected it might not, because worn rings usually display more issues on startup and a cold motor, rather than warm. Though give her a chance to break in to see if the situation improves.

I'm not an expert in small motors by any means, but definitely have some experience with modern car motors.

Power degradation after operating awhile could be a sign of heat soak. Causing the engine to not be able to run as much timing, or that the intake air becomes more heated and less dense. Not sure how these small motors handle timing. But certainly the latter could be an issue depending on environment the generator is run in. If it's a smaller, more enclosed area, the exhaust and motor could certainly heat up the intake air in the vicinity. Wonder if that might be possible in your or Trailbob's scenarios?

[Micro-Air]

Originally Posted by pteck

Matteo, sorry to hear your engine refresh with new piston rings did not help. I suspected it might not, because worn rings usually display more issues on startup and a cold motor, rather than warm. Though give her a chance to break in to see if the situation improves.

I'm not an expert in small motors by any means, but definitely have some experience with modern car motors.

Power degradation after operating awhile could be a sign of heat soak. Causing the engine to not be able to run as much timing, or that the intake air becomes more heated and less dense. Not sure how these small motors handle timing. But certainly the latter could be an issue depending on environment the generator is run in. If it's a smaller, more enclosed area, the exhaust and motor could certainly heat up the intake air in the vicinity. Wonder if that might be possible in your or Trailbob's scenarios?

Thanks for the condolences, Pteck. I think I'm over my pity party and ready to go on the attack again! Since I don't want to take this thread off track, I'm going to keep all of the gory details of my Honda power loss investigation in the other forum (thread link here). If and when I come up with a solution, I'll certainly share it here for everyone's benefit. BTW, the Honda EU2000i generator I'm working on was owned by an Airstream customer. I felt compelled to move ahead with this investigation since the 1 or 2% affected like Trailbob might benefit down the road.