Can Generators Run Both AC's While Boondocking?

[ShullsinUtah]

Just pulled the trigger on a 364. Hopefully it will be here before the long weekend (opted for 2 day shipping) and I can install it Sun or Mon. (We taking this weekend off and going out next weekend after school gets out.)

[hoagy_007]

Just bought the Honda eu2200i and companion eu2200ic. Hooked up to my 2018 30' FC AS and AC's started with no problems. Even kicked on the fridge, tv, lights but no microwave so far. But with all those systems on the geni's purred along and didn't stress out at all. Also ran fine in eco mode.

Hoagy

[ShullsinUtah]

Originally Posted by ShullsinUtah

Just pulled the trigger on a 364. Hopefully it will be here before the long weekend (opted for 2 day shipping) and I can install it Sun or Mon. (We taking this weekend off and going out next weekend after school gets out.)

I got the unit in the noon mail on Saturday, and had it installed by dinner time on Saturday. We have an older Dometic Penguin on our 2006 Safari. The actual install time only took about 15 mins, but I was going extra slow as to be thorough. That included a trip to home depot and the local autoparts store to buy connectors and a grommet. The install kit included a grommet, but it was a little large for the space where I was working and I wanted something smaller. I wanted to use quick disconnects so I could easily remove the unit if I needed to. I used a suitcase connector to connect to 3 way connection to the main white wire to the compressor.

The unit worked no problem on 20 amp shore power from the garage. It did the 5 program starts that way. It did trip the breaker in the garage when I turned the fridge from gas to auto/A/C. (I thought I had turned off the thermostat to go inside but I had not.) Went to open the garage doors and they wouldn't go up. No harm no foul.

However, I couldn't not get the A/C unit to run at 100% efficiency when connected to our 1800W (continuous power rating) Ryobi generator. I will add that we are at almost 5,000', so that 1800W at our house is closer to 1,500W. I want to try again at a lower elevation (we'll have the chance on our cross country trip this summer). The unit would blow cool air, but not COLD like I could get from shore power. However, I'm nor sure if that was because the chiller unit had already been cooled from being connected to shore power. A wee bit disappointed, but it has zero to do with the operation of the 364, just the limitations of our equipment and what we're asking it to do.

It's been cold and rainy here the past two days so I still have some trouble shooting to do. I'd love to try the unit with a Honda 2000 or other generator to see what would happen. I want to hook the trailer up to the ryobi on a warmer day and let it run for a while to see if it makes a difference.

I will tell the forum like I told my wife when I got done with the install, This is THE BEST money we've spent on the trailer since we bought it. I know that any A/C outlet that I can find will cool the trailer. It makes us a lot more versatile.

[SailorSam205]

Originally Posted by ShullsinUtah

However, I couldn't not get the A/C unit to run at 100% efficiency when connected to our 1800W (continuous power rating) Ryobi generator. I will add that we are at almost 5,000', so that 1800W at our house is closer to 1,500W.

I'm a little confused (which is pretty much normal ). Are you saying that with the Easy Start installed, the compressor started while on the generator but once started, did not produce the same amount of cooling you get when plugged into A/C?

My understanding of this issue is that the problem most folks encounter is that the generator doesn't have the power to start the compressor without an Easy Start installed. But once started, even without an Easy Start, the generator has enough power to "run" it.

IMNTK

[ShullsinUtah]

Originally Posted by SailorSam205

I'm a little confused (which is pretty much normal ). Are you saying that with the Easy Start installed, the compressor started while on the generator but once started, did not produce the same amount of cooling you get when plugged into A/C?

And my honest answer is, I don't know if it started the compressor or not.

When I was connected to shore power, 5 mins after a restart of the AC system, I could tell a noticeable decrease in the air temp coming out of the register. It was COLD. When connected to the generator, I never noticed the significant decrease in air temp. BUT, this was after doing the 5 programming starts, so the AC coils were already cool. I wasn't on top of the roof so I can't say for certain if the compressor was on or not and just wasn't running at 100% efficiency. On the flip side of things, the generator never bogged down and never overloaded. It seemingly just ran the fan. I tried in both "eco" mode (Ryobi calls it "auto idle") and standard mode. It could have started the compressor, I do not know. I just know the air wasn't as cold as on shore power. (I'll note that this is not an uncommon occurrence running appliances with this generator. It seems our little 900w microwave takes longer to heat things up and my wife's hair dryer doesn't blow as hot either. Both of those things are things we rarely do when traveling/camping.)

When it gets warm again, I'm going to do a test of just the generator and see if it will cool the trailer on it's own. It's supposed to hit the mid 80's today so it might be today or tomorrow if I have time. I'll report back with my results.

[switz]

Not enough generator capacity. To run both, one needs to be looking at a generator in the 7,000 watt class with a fifty amp power outlet. The issue is the start up surge load if both units start at the same time with other A/C devices running. A background load not seen is the battery charger which comes on when necessary and adds a significant additional load to the generator.

We have a large solar array on the roof of 900 Watts which coupled with the 600 amp hour lithium batttery can even run one A/C unit for awhile with no generator.

The 23D has 500 Watts of solar and coupled with the Magnum hybrid MS3012 inverter charger that can draw the inrush current from the 300 amp hour lithium battery will run the A/C with a single 2,000 watt Honda generator.

[franklyfrank]

Originally Posted by SailorSam205

I'm a little confused (which is pretty much normal ). Are you saying that with the Easy Start installed, the compressor started while on the generator but once started, did not produce the same amount of cooling you get when plugged into A/C?

My understanding of this issue is that the problem most folks encounter is that the generator doesn't have the power to start the compressor without an Easy Start installed. But once started, even without an Easy Start, the generator has enough power to "run" it.

IMNTK

This is one confusing overwrought thread.
I use a Champion 3100W Inverter generator. Plop it on the ground, start it,
plug in the cord, turn on the AC units and presto she purrs for 8 hours without any headaches. To keep reserve power I do run the fridge off LP if I need to run the AC units.

[Mollysdad]

Originally Posted by switz

. The issue is the start up surge load if both units start at the same time with other A/C devices running.

Here's tip from my Airstream salesman. If you have two A/C's, and on ample power, set the thermostats a few degrees apart. For instance, the front at 73 and the rear at 75. That way the compressors won't kick in at the same time, and you'll never notice any difference.

Originally Posted by franklyfrank

I use a Champion 3100W Inverter generator. Plop it on the ground, start it,
plug in the cord, turn on the AC units and presto she purrs for 8 hours without any headaches.

You're running two A/C units off a Champion 3100? I assume you have a 30 amp to 50 amp dogbone.

[franklyfrank]

Originally Posted by Mollysdad

Here's tip from my Airstream salesman. If you have two A/C's, and on ample power, set the thermostats a few degrees apart. For instance, the front at 73 and the rear at 75. That way the compressors won't kick in at the same time, and you'll never notice any difference.

You're running two A/C units off a Champion 3100? I assume you have a 30 amp to 50 amp dogbone.

Yes and yes. I set the temperatures 3 degrees difference so they never start at the same time however on occasion they do but if the Gen is revved up no problem. With the ducted Air most of the time I only need to run the 15k AC.

[ShullsinUtah]

Originally Posted by ShullsinUtah

When it gets warm again, I'm going to do a test of just the generator and see if it will cool the trailer on it's own. It's supposed to hit the mid 80's today so it might be today or tomorrow if I have time. I'll report back with my results.

So I spent about 20-30 mins testing the AC with just the generator. Temps were in the High 80's-low 90's with about 20% humidity. The outside and inside thermometers were reading 91 at the start of the test. When I first fired up the generator, I went in the coach and set the thermostat to 72 and fan on Auto. Literally nothing happened. The fan did not kick on, the A/C did not kick on. After about 2 mins of waiting for something to happen, I turned the fan from Auto to low. The fan on the AC started to run. After about another 1-2 mins, I heard the compressor cycle, the generator sped up, and the unit started to blow cold air. This continued for about 5 mins or so. Then the compressor bogged down, the generator slowed to idle and the A/c unit ceased to blow cold air and was only blowing "cool" air. The 5 mins or so the AC did run dropped the trailers internal temp a couple of degrees.

After 5 mins, when the easy start had gone through it's 5 min waiting cycle, I heard the compressor bog down again, and failed to cycle. This continued 2 or 3 more times until a brief thunderstorm rolled in and I stopped testing.

The good news was I got 1 cycle out of the compressor with the generator and easy start. The bad news was I couldn't maintain the load. This makes me think even more strongly that it's related to our elevation (5,000') and we are right on the cusp of being able to make things work. I don't know what other loads might be stealing watts from the generator that would cause this not to work. I had the fridge on gas and everything else off in the trailer during the test. I do not know if the inverter was thing to charge the house batteries or not.

[Micro-Air]

Originally Posted by ShullsinUtah

...The bad news was I couldn't maintain the load. This makes me think even more strongly that it's related to our elevation (5,000') and we are right on the cusp of being able to make things work. I don't know what other loads might be stealing watts from the generator that would cause this not to work. I had the fridge on gas and everything else off in the trailer during the test. I do not know if the inverter was thing to charge the house batteries or not.

Hello Shulls. I agree with you because your 1800W Ryobi at 5000' will only be good for about 1530W sustained. Assuming you have a 13.5kBTU Dometic Penguin II rooftop, those can draw over 1600W in warm weather. You are operating on the cusp as you say, and it has nothing to do with EasyStart. What's happening is the output voltage from your generator is collapsing, resulting in a compressor stall, which the EasyStart immediately detects and disconnects the compressor, resulting in no further issues. Without EasyStart, such a stall would have resulted in locked rotor amperage for 3-5 seconds, and then the compressor's thermal overload protector would have popped open. That's not good for the compressor or the overload itself, but you are protected from any harm with EasyStart.

[ShullsinUtah]

Originally Posted by Micro-Air

Hello Shulls. I agree with you because your 1800W Ryobi at 5000' will only be good for about 1530W sustained. Assuming you have a 13.5kBTU Dometic Penguin II rooftop, those can draw over 1600W in warm weather. You are operating on the cusp as you say, and it has nothing to do with EasyStart. What's happening is the output voltage from your generator is collapsing, resulting in a compressor stall, which the EasyStart immediately detects and disconnects the compressor, resulting in no further issues. Without EasyStart, such a stall would have resulted in locked rotor amperage for 3-5 seconds, and then the compressor's thermal overload protector would have popped open. That's not good for the compressor or the overload itself, but you are protected from any harm with EasyStart.

Thanks Matteo. We have a 13.5K Penguin 1 so I suspect the operating watts are just at tad bit higher.

The good thing about living in the high desert is it usually cools off quickly at night so AC is not too much of an issue here. As we travel east and down in elevation I feel we have a better shot at making things work.

What I forgot to add to my testing post is that I plugged into shore power and she started blowing cold air as soon as the easy start reset itself after 5 mins.

I still wholeheartedly endorse the product. I knew the limitations going in, and actually anticipated this result. Again, the limitations here are based upon the genset and elevation, not the ES364.

[Micro-Air]

Originally Posted by ShullsinUtah

Thanks Matteo. We have a 13.5K Penguin 1 so I suspect the operating watts are just at tad bit higher.

You are indeed correct, Shulls. I've measured exactly that first hand. The original Penguin, which I also like to now call the "Penguin I", draws about 1.5A more than its newer counterpart.

[SailorSam205]

Thanks Shulls for the post. Good and useful information.

[Big Vic]

I installed the ES 364 on my 2008 Dometic Brisk I 15K A/C. Double checked all connections, and did the 5 starts on a 30A shore power receptacle. A/C worked fine on the 30A shore connection. Much quieter compressor start just a few seconds after the fan starts. While running on shore power, the running amp draw from A/c varied from 10-15 amps as measured by my EMS display.

Next, hooked up my Hutch Mountain propane fueled Honda EU2000 with eco mode off and let it warm up. Everything else in RV off (no water heater, converter or fridge on electric). At sea level with outside temps about 85 deg. Fan went on but genny stalled when compressor came on.

Then hooked up my second propane fueled Honda 2000 in parallel - after which all was good. This time started up A/C when in eco mode on the two Hondas. With A/C running, the Hondas were both easily running at only a bit more RPM than with no load.

So my 15K Dometic Brisk I A/C was not able to run on a single propane fueled Honda 2000 with ES 364. Not too upset about this, because running the two Honda 2000s will let me also run other things while running the A/C.

I will test later with gasoline fueled Honda to see if there is any difference from running on propane, but from what I have read, there is only a 2-3% drop in genny power on propane.

I am guessing that my Honda 2000 was right on the borderline for amperage, and that the new Honda 2200 or Westinghouse 2500 would be able to run the A/C solo under those altitude and temp conditions.

[Micro-Air]

Originally Posted by Big Vic

...So my 15K Dometic Brisk I A/C was not able to run on a single propane fueled Honda 2000 with ES 364. Not too upset about this, because running the two Honda 2000s will let me also run other things while running the A/C.

I will test later with gasoline fueled Honda to see if there is any difference from running on propane, but from what I have read, there is only a 2-3% drop in genny power on propane.

I am guessing that my Honda 2000 was right on the borderline for amperage, and that the new Honda 2200 or Westinghouse 2500 would be able to run the A/C solo under those altitude and temp conditions.

Hi Big Vic. What you described should have worked. I have a few questions for you:

1) It is possible to mis-wire the EasyStart in such a way that it is still hard starting and not soft starting. This can fool you because it'll seem to work on utility power, but then not work on generator. The best way to know if you wired it correctly is to see if you notice the 5-minute short-cycle prevention timer preventing the compressor from re-starting quickly if you power off the system and immediately power it back on again. The symptom you'll notice is the fan will run, blowing warm air, and the compressor restart will be held off for 5 minutes. Was this in fact happening during your 5 learning starts?

2) When you reported that the generator "stalled" when the compressor attempted to start, did it light its Overload Fault LED, or did it just lose output power and bog down?

3) What altitude are you at? The power loss is 10% with propane right off the bat, and 3% per thousand feet of altitude.

If you want, you can PM me the answers in case we end up in a long back-and-forth conversation. Thank you for your patience.

[silverhio]

Originally Posted by ShullsinUtah

And my honest answer is, I don't know if it started the compressor or not.

When I was connected to shore power, 5 mins after a restart of the AC system, I could tell a noticeable decrease in the air temp coming out of the register. …

Shulls, did you ever try this at a lower altitude?
I think I have almost the exact setup. Ryobi 2200/1800 inverter generator and a 1997 Penguin 13,000 or 13,500 unit.

I made a really nice front hitch carry tray for Ryobi and love how small and light it is. If I can make it work below 5,000 I'd be happy. I think most of my above 5,000 stays are cool enough to not need so much AC, but lower in the deserts I'd like AC. At $300 this is easier than switching to a Polar Cu 9,000btu unit.