2000w Generator and Dometic 11,000

[C&G in FL]

Originally Posted by Shiny

Congrats! I'm sure this made you happy.

What was the altitude?

We were camping at 10,200 ft and found our 2000W Champion would not power a Keurig. As I understand, this brewer eats 1500 Watts, so the power loss is consistent with the altitude derating estimate I posted earlier.

I'm still debating whether I can find a "low weight" single generator solution to powering our AC where we typically camp (7000 to 10000 ft).

I think a 2200 W Generator under 60 lbs would be a great solution, but it's just not yet clear if this would power our AC, even with a soft start.

Even better would be a propane-powered generator but that has another "derating" penalty vs gas. I haven't looked too hard but I'm not aware of a 3KW generator that I want to lug around so I may have to accept running two 2KW units.

I’m kind of wondering why you would need A/C at 7,000 feet. How often do you get temperatures that require A/C at that elevation. I do a lot of camping between 3,000 and 3,500 feet in the Appalachian Mtns. in NC and rarely need A/C, even in July and August when temperatures are typically in the mid to high 70s. I’m not being critical; I’m just curious. Then again, I’m from Florida and I am somewhat acclimated to heat, even though I like it cool for sleeping.

[Upfisk]

Originally Posted by C&G in FL

I’m kind of wondering why you would need A/C at 7,000 feet. How often do you get temperatures that require A/C at that elevation. I do a lot of camping between 3,000 and 3,500 feet in the Appalachian Mtns. in NC and rarely need A/C, even in July and August when temperatures are typically in the mid to high 70s. I’m not being critical; I’m just curious. Then again, I’m from Florida and I am somewhat acclimated to heat, even though I like it cool for sleeping.

If you live in Arizona the North Rim of the Grand Canyon is 9000 ft and Flagstaff is 7000 ft. On a hot afternoon Flagstaff can be in the low 90s. We have been at Jacob Lake, near the North Rim in the high 80s in the afternoon. Yes, we ran our A.C. for an hour in the afternoon. Nights, no problem as it cools off to 70 or cooler. Arizona is kinda hot in the summer, even at higher elevation.

[Shiny]

Originally Posted by Upfisk

If you live in Arizona the North Rim of the Grand Canyon is 9000 ft and Flagstaff is 7000 ft. On a hot afternoon Flagstaff can be in the low 90s. We have been at Jacob Lake, near the North Rim in the high 80s in the afternoon. Yes, we ran our A.C. for an hour in the afternoon. Nights, no problem as it cools off to 70 or cooler. Arizona is kinda hot in the summer, even at higher elevation.

This!

Without humidity to dampen the swings, the highs are higher and the lows are lower. Living at 6000', our summer highs are typically ~95 but often push 100. Most USFS campgrounds nearby are 8000' to 10500' and while cooler, it often hits 80 to 90 in the afternoon. If there is no shade, the trailer and ground absorb a lot of heat and we want AC in the afternoon.

Everyone's "comfort zone" is different. Here's a chart showing the "typical". It's pretty accurate for me:

[C&G in FL]

Originally Posted by Upfisk

If you live in Arizona the North Rim of the Grand Canyon is 9000 ft and Flagstaff is 7000 ft. On a hot afternoon Flagstaff can be in the low 90s. We have been at Jacob Lake, near the North Rim in the high 80s in the afternoon. Yes, we ran our A.C. for an hour in the afternoon. Nights, no problem as it cools off to 70 or cooler. Arizona is kinda hot in the summer, even at higher elevation.

Thanks for responding. I’m guessing those locations would be considered “high desert.” But hen I asked the question, I was thinking high altitudes in the Rocky Mountains such as in Colorado and some of the well known passes, etc. The last time I was at the Grand Canyon (South Rim) it was 100° F at the top and I was told by a ranger, 125° at the bottom. But I was under the impression the South Rim was approximately 1 mile above SL. It must be more than 5280’ however, because the North Rim is definitely not 4/5ths of a mile higher than the South Rim, at least not by visual appearance. I can understand the need for A/C to cool the trailer down, even if temps drop rapidly after the sun goes down.

[dfandrews]

Originally Posted by Shiny

This!

Without humidity to dampen the swings, the highs are higher and the lows are lower. Living at 6000', our summer highs are typically ~95 but often push 100. Most USFS campgrounds nearby are 8000' to 10500' and while cooler, it often hits 80 to 90 in the afternoon. If there is no shade, the trailer and ground absorb a lot of heat and we want AC in the afternoon.

Everyone's "comfort zone" is different. Here's a chart showing the "typical". It's pretty accurate for me:

Ahh, the ASHRAE Comfort Zone.
It took me quite an amount of time (when younger, of course), before I quit trying to tell people that they are indeed comfortable, because their A/C unit was giving them temps and RH levels in the middle of the Comfort Zone!

[John in Santa Cruz]

Btw, most generator brands advertise the VA rating rather than wattage as it is a larger number due to AC inductive loads. I have a cheap"2000VA" generator that can only handle 1300 watts sustained.

[Shiny]

Originally Posted by John in Santa Cruz

Btw, most generator brands advertise the VA rating rather than wattage as it is a larger number due to AC inductive loads. I have a cheap"2000VA" generator that can only handle 1300 watts sustained.

Please forgive my ignorance but are you saying when the generator states "Startup Watts" they mean VA? In other words, is the difference between advertised "Startup Watts" and "Running Watts" accounting for inductive loads vs resistive?

How much of the AC unit's startup current is "reactive" or inductive vs mechanical?

What is a "Soft Start" actually doing? Is it compensating the reactive loads (ie adding capacitance)? I assume it is more complicated...

Does a Soft Start add stress to the AC motor (thermal or bearing wear) by slowing down the start-up time?

[John in Santa Cruz]

startup watts is watts it can only output for like 1 second, maybe less. running watts is supposed to be sustained output.

the 'soft start' kits for an A/C do indeed slow down the motor startup, so as to reduce the initial current peak. this should not increase the stress in the motor

[MyronL]

The only stress for me was the soft start purchase price. I got over that, then it came back when I found my 13000 BTU shutting down after 25 minutes on the Wen, it running short of the needed ac wattage. Ah, who needs ac anyway. Well, I am at 6700 feet.

[Iowa Dave]

I bought a 2200i Honda a year ago on August 11. I used it for 11 days to keep my 17 cu ft freezer full of frozen food from thawing out. And to open and close my garage doors when I did not have electricity. I tried it at 600 ft elevation to run the AC on the 21. The EMS immediately kicked out when I turned the compressor on. Tried about three times. Bought and installed the soft start. Went camping and used the air 4 days from about 2 PM to 5 PM so the grandkids could get a nap. Then used it from about 8pm’ to 10pm to cool the trailer off and then opened the windows to sleep. Justified the whole expense by rationalizing that my stimulus money needed spent. Thanks. I do not like to camp where it’s real hot or real high (above about 8,000ft) so the Honda and the Softstart work for us on 85 degree days with 85+ percent humidity.
Of my own calculation if the temperature times the humidity in Iowa is 6400 or more, I don’t do much work and even less walking around.
Remember, you will not often see a hearse stop at a bank to make a withdrawa. Spend money, stimulate the economy. Buy Local and when possible support your country by purchasing quality goods made there. The soft start is made in USA. If you are looking for a good pocket knife, Case is made in Bradford PA.
As always YMMV. The Canadian Escape is my choice for a good fiberglass trailer.

[cpaharley2008]

Zippo lighters are made there also.....

[Shiny]

Originally Posted by Iowa Dave

.... Bought and installed the soft start. ... Justified the whole expense by rationalizing that my stimulus money needed spent. Thanks. ...Spend money, stimulate the economy.....

My standard answer when asked "how do you want to pay for this?" is "with somebody else's money".

[Radar1]

I had a A-IPOWER 2300 surge/1800 running watts generator I picked up at Sam's club before I got our Escape. Tried running the Dometic A/C (model 640310C451C0) with all other electrical loads off, 900' MSL. It tried to start it but just got a lot of clicking from around the EMS and the A/C fell back to fan only mode (wouldn't start the compressor).
I decided to install the Microair Easy start to see if that would allow the generator to start the A/C. Unfortunately, even though the A/C seems to start the compressor smoother on AC power, it still doesn't start on generator power. Now I have to decide if I want a bigger generator, a Honda 2200i that people seem to have success with easy start, or get another generator and pair them up. That is, if I want to bother even taking a generator on camping trips (so far I haven't used a generator in 10 years with our Scamp or 2 years with our Escape).
I'm also wondering if all these Dometic Penguin A/Cs are the same, as some have added heat strips, but Dometic says my model isn't capable of accepting one. I think mine is 11,000 BTU but can't find any reference from Dometic to confirm that. I do know that based on EMS readings with easy start installed, the A/C compressor and fan seems to run on 9.0 amps, and it looks like it pulls at least 19.0 amps starting.
According to a label on my A/C, it pulls 9.1 amps running, and locked rotor amps (LRA) are 56, plus 2.6 for the fan. Both those values are higher than the other 3 Penguin IIs in the same manual. Dometic says you only need a 2.5 KW generator.

[Bill and Earline]

I'd borrow somebody's Honda 2200i, to see if your AC starts on that one.

In doing a little reading, it seems your engine is about 79cc and Honda's is 121cc.

[WillyB]

A couple of videos that might help some of us less "electrician" qualified folks. It was interesting to watch the voltage drop.

Plus, regardless of the brand, all generators lose 3.5% power every 1000 feet of elevation.

https://www.youtube.com/watch?v=m4PQ_062Dqs

https://www.youtube.com/watch?v=MkcbfnbP8Xc&t=463s

[Shiny]

Thanks for the YouTube links. I watched the Champion comparison and thought it was objective and useful.

[ksitte]

Originally Posted by Bill and Earline

I'd borrow somebody's Honda 2200i, to see if your AC starts on that one.

In doing a little reading, it seems your engine is about 79cc and Honda's is 121cc.

Our Honda EU2200i easily starts our 11,000 btu Dometic AC. I too installed the Microair Easy Start and we run the Honda genset using propane only, running off the Escape exterior propane quick connect. We've had no problems even at higher altitudes. (We live & camp a lot in Montana.)

IMHO, Bill/Earline's suggestion to borrow a Honda is a great idea. At the very least, Radar1 would get comfortable with how well it all works together. Like Radar1, we only occasionally take the Honda along. It's nice to have backup in the shoulder seasons when solar may not fully recharge the batteries dependably. The Honda is so remarkably quiet and relatively light that it's nice to have along.

[7Gentex]

My 10 (?) year old Honda eu2000i, on a Hutch Mountain propane conversion, also starts and runs my 11k Dometic Penguin II Air Conditioner 640310CXX1C0 with no problems off the low pressure port. I use a 1/4" male to 3/8" female quick connect adapter for the quick connect as the standard Hutch Mountain setup is all 3/8".

I have not tried it over 90F ambient yet, nor at altitude.

[Lanark Camper]

I have a 2019 E17B with factory Dometic AC no soft start. I have an older Honda EU2000 generator. I have the neutral tied to ground. The AC starts and runs if fine. No elevation to speak of, so no idea what might happen in high elevations.
I made my own adaptor with hardware store parts and some left over 12 ga stranded wire.
Bob

[John in Santa Cruz]

Note generators are usually rated in VA, Volts*Amps, which are not the same as watts in AC (alternating current). VA is generally higher than the watts, I guess thats why they like to advertise it. Any given AC appliance has a 'power factor', or PF, which ranges from 1.0 for a purely resistive load to less than 1 for a inductive load like a motor or transformer. A typical PF is 0.8, so 2000 VA would be 2000 * .8 = 1600 watts.