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A/C Overloading My Generator

CJ97
Explorer
Explorer
First time TT owner here--so I'm hoping I'm just doing something wrong that is very simple.

We have an Apex with a 13500 BTU A/C. The generator is a Honda EU3000i Handi (Max: 3000W, Continuous: 2600W). I hooked up the generator to the TT and was getting power to the TT. However, when I tried to turn on the A/C, the overload light on the generator went on after a few seconds and cut the power output. I have tried it a couple more times, always with all the big items turned off (frig, microwave, etc.). I have even tried it with only the Main and A/C circuit breakers on. Each time I get the same result.

Everything I've read seems to indicate that my generator should be sufficient to run a 13500 BTU A/C.

Does anyone have any suggestions? What are the troubleshooting steps for this?
27 REPLIES 27

Dirtclods
Explorer
Explorer
jwandvassie wrote:
Ivylog wrote:
After 30 minutes of the generator hooked to you TT plug, try starting the AC. This will give your converter time to charge your batteries hopefully to where you have enough power to start the AC.


Best answer so far.


Or after the generator is started pull your disconnect for you batteries and see if you have the same issues.
AAA Motorcycle RV Plus

Dirtclods
Explorer
Explorer
On your frig sometimes the auto switch does not transfer so switch it to gas/propane. Let me know if it makes a difference.
AAA Motorcycle RV Plus

FoCoNoCo
Explorer
Explorer
However, adding too much capacitance, unless using a potential relay, can damage motor windings and shorten motor life.

mikestock
Explorer
Explorer
First I would try one of these.
I have seen this before. I ran 15k air conditioners for years on three different fivers with a Honda Eu3000is, but I've seen others tailgating with the same generator and a 13.5k unit that just wouldn't start. One fellow, in particular, went so far as to replace the ac with a high efficiency unit and never had another problem.

One last thought: I would not hesitate to parallel one of these capacitors with whatever may be present under the housing cover. Paralleling capacitors (different from resistors) results in adding capacitance, which can only help.

SoundGuy
Explorer
Explorer
CJ97 wrote:
Here's the website for the soft starer (http://www.microair.net/main/products/product.php?id=20).

Has anyone out there ever installed one of these? It looks like it retails for about $350 (plus installation), but if it can really reduce the peak start watts as much as it says ("up to 65-75%"), then that could really be worth it.


Lots of testimonials, here's one. Frankly, now that soft starters like the Micro-Air are now available there's no reason to waste you time & $ adding a hard start cap like an SPP6 as it won't come anywhere near close to the performance of the Easy Start. As exterior ambient temperature and elevation rise you'll have the same starting issue, regardless of the SPP6. Add an Easy Start to your 13,500 BTU A/C and a much lighter, less costly EU2000i will easily start it. :B
2012 Silverado 1500 Crew Cab
2014 Coachmen Freedom Express 192RBS
2003 Fleetwood Yuma * 2008 K-Z Spree 240BH-LX
2007 TrailCruiser C21RBH * 2000 Fleetwood Santa Fe
1998 Jayco 10UD * 1969 Coleman CT380

CJ97
Explorer
Explorer
UPDATE: Success! (Or at least significant progress.)

-So yes, according to the AC manufacturer (Dometic), they recommend a 3500W generator to handle the peak loads on my model (which is 13.5K BTU)
-I installed the Supco SPP6 hard start kit (http://www.supco.com/web/supco_live/products/SPP6.html)
-I also ran the fan on low for a while, waiting a little bit before I changed the setting to "cool"

With all that, the generator did not fail! I didn't watch the generator to see if it flashed the overload light or not, but the good thing is it kept providing power. I tested this three times.

However, things that may yet prove troublesome:
-How it performs in hotter weather
-How it performs in higher elevation

I'll get to test all of these soon, as we leave for a 3-week "shakedown cruise" next Saturday, going up to Reno and then NorCal (coastal), then back down through the valley, Pismo, then back to SD. I'll update you all when I return.

One more thing, in my research I found a couple with an RV that ran their AC completely off solar. You can see their blog & videos here (http://www.gonewiththewynns.com/off-grid-solar-rv-air-conditioning). The piece that interested me is the component that they eventually installed, which is called a "soft starter" (this may be what you were referring to, DSteiner51), as opposed to a hard start kit (like the cheap one I installed). Here's the website for the soft starer (http://www.microair.net/main/products/product.php?id=20).

Has anyone out there ever installed one of these? It looks like it retails for about $350 (plus installation), but if it can really reduce the peak start watts as much as it says ("up to 65-75%"), then that could really be worth it.

Blessings to all of you,

CJ

DSteiner51
Explorer
Explorer
My 2800w generator wouldn't start my13.5 AC with eco mode off. After I installed the soft start kit it would start it with the eco mode on.
D. Steiner
The sooner I fall behind, the more time I have to catch up.

jwandvassie
Explorer
Explorer
GordonThree wrote:
I'm not sure why I got the privilege of being ranked worse answer.

I wasn't able to reliabily start my 13.5 with 4000 watts of generator (2x 2000 watt).

Adding the missing start capacitor fixed my issue. A/C starts and restarts without issue even at triple digit temps.


My apologies sir. Further research revealed that your answer was indeed a very possible solution.

troubledwaters
Explorer III
Explorer III
Are you positive its a 13.5K AC? Could it possibly be a 15K AC?

SoundGuy
Explorer
Explorer
CJ97 wrote:
Everything I've read seems to indicate that my generator should be sufficient to run a 13500 BTU A/C.

Does anyone have any suggestions? What are the troubleshooting steps for this?


Although one might suspect there's an issue with your A/C since your 3K Handi won't start it I'd nonetheless install a soft starter such as the Micro-Air Easy Start Soft Starter Kit on the A/C. More and more testimonials confirm how well it works, with every one I've read saying even a 2K genset such as Honda's EU2000i will easily start a 13,500 BTU A/C. :B
2012 Silverado 1500 Crew Cab
2014 Coachmen Freedom Express 192RBS
2003 Fleetwood Yuma * 2008 K-Z Spree 240BH-LX
2007 TrailCruiser C21RBH * 2000 Fleetwood Santa Fe
1998 Jayco 10UD * 1969 Coleman CT380

hotpepperkid
Explorer
Explorer
GordonThree wrote:
Your a/c unit is likely missing it's starting capacitor. The factory leaves them out for some reason.

Supco has basic capacitor kits... There's much more expensive versions out there as well.


X2 The trailer manufactures leave them out because it is cheaper that way. Been down that road.
2019 Ford F-350 long bed SRW 4X4 6.4 PSD Grand Designs Reflection 295RL 5th wheel

GordonThree
Explorer
Explorer
I'm not sure why I got the privilege of being ranked worse answer.

I wasn't able to reliabily start my 13.5 with 4000 watts of generator (2x 2000 watt).

Adding the missing start capacitor fixed my issue. A/C starts and restarts without issue even at triple digit temps.
2013 KZ Sportsmen Classic 200, 20 ft TT
2020 RAM 1500, 5.7 4x4, 8 speed

Searching_Ut
Explorer
Explorer
On the plus side, your troubleshooting so far seems logical and provides good information to work with. As for your dealer???, I know a lot of folks running 13.5k air conditioning units on that particular generator.

Don't know what the comment on the starting capacitor was all about. My timber ridge tt had a coleman 13.5k ac unit that wouldn't start with two paralleled 2000 watt generators until I added a start capacitor. Why soft start caps aren't standard equipment on all units is beyond me. They can extend the life of the compressor motors as well as making them less demanding on your generator.

As for an easy way to test the generator to see if it is having issues, what other means do you have to put a load on it? Being a 3000 watt unit you'll want to use the 30 amp plug, maybe power up your trailer and try running maybe a hair dryer, and some other high drain item on a separate circuit breaker inside the trailer. The problem will be having a good idea of how much of a load you're actually putting on the generator. If you have a kill-a-watt it would give you a good idea of what individual things you're plugging in draw power wise. Access to a load bank would be really good, but unfortunately I only know a few folks with access to those.
2015 Ram 3500 Laramie CTD, 4X4, AISIN, B&W Companion Puck Mount
2016 Heartland Bighorn 3270RS, 1kw solar with Trimetric and dual SC2030, 600 watt and 2k inverters.

bgum
Explorer
Explorer
The dealer is uninformed. I have a Honda 3000 and a 13500 AC. It is easily run by the gen. You are experiencing a problem with either the AC or the gen. Does someone have a meter to check the gen output?