If you know the size of your AC unit you could look up the max amp draw on the manufactures site. My boat has two units, a 5,000 in the salon and a 7,000 in the master stateroom. I can tell you then when the compressors first kicks on the ammeter really jumps to at least 20 amps. My units are both on the same 30 amp circuit and have a timing device so that they dont both try to start up at the same time. You probably have a pretty good sized unit in your boat so it is not hard for me to think that you are pulling more thatn the 16 amp max output of your generator. The controler for your unit is shutting it down due to low voltage caused by the high amp draw. Running the portable generator is a whole other subject that has been beat to death on this site so I wont got there, but for my .02 I wouldn't do what you are doing.

 

My startup hits at 28/30 amps. I dont see how your going to even get close with that Gen. Im sure you know about how your settup could be unsafe. Goodluck...

 

The intent wasn't to run it all night, but to have it when needed. There are a lot of people who have them on their boats, portables that is. They cool off the cabin or charge their batteries when needed. We were just going to use it during the day to cool off the cabin and that was about it. We are in the markert any way for a larger boat, so the next one for sure will have a gene in it. Hard to find boats here with gene's. In warmer climates they all have them, but around here in Chicago, you don't see a lot of them having them till you go with a larger boat.

 

OK....help a brother out! I'm considering exactly the same generator on a 2000DA 290....what where you able to fine out? Waste of $$? 2nd Genny (still cheaper than onboard!)?

 

....I know that are boat isn't pulling more then 20amps, because that is all we have a circuit breaker for when we are on the shore power at our dock.

EU2000i Specifications - 120V 2000W max. (16.7A) 1600W rated (13.3A)

I get it.

Your logic goes like this. We have a 20 Amp circuit breaker on shore power. We turn on the A/C on shore power. The breaker does not trip. Therefore we never draw more than 20 amps.

This logic is incorrect.

The 20 amp circuit breaker has two trip units. One thermo and one magnetic. Both trip units actually trip a mechanism that causes a separate trip unit to release a fast mate / fast break spring loaded switch.

OK, the first trip unit I said was magnetic. This only trips in a short circuit situation. It takes a load way above 20 amps and will trip virtually instantly, as little as a few cycles, so a fraction of a second. Even a 30 amp load would not come close to tripping this mechanism.

The second trip unit is thermo, basically two dissimilar metals with different rates of expansion. The electricity runs thru the two metals and as the loads increase the metals expand to the point that under a load above the stated amperage the fast break trip mechanism is tripped.

On the thermo trip mechanism there is something called a time / current trip curve. A 20 amp breaker under 20 amp load is designed to never trip. At 25 amps it takes bout ½ hour to trip. As the load gets higher and higher the trip time gets shorter but is always greater then instant.

So you can pull well over 20 amps thru a 20 amp circuit breaker for a brief period.

 

After making the usual disclaimer about portable gens on a boat...
You need to look and see what you have for an air conditioner. There will be a plate on it with at least the manufacturer and model number, maybe even the electrical requirements you're looking for. Start up amps depend on the motor/compressor, but can be 1.5 times as much as the running amps. Add another amp for the seawater pump.

If it works on paper, perhaps the motor/compressor has a problem which is causing execessive resistance.

 

Our last boat (32' Wellcraft St Tropez) had a 12000 BTU Marine Airrrr unit that was able to be powered by our Honda 2000 inverter/generator. My buddies boat had a 10000 BTU Mermaid A/C unit and the same genny would NOT start his A/C.

Remember, it's not just the A/C unit starting but also the raw water pump at the same time.

You might want to temporarily disconnect the pump wiring to see if the A/C compressor will start with your genny. If it does (it will soon shut off since there is no cooling water) you might want to either put a time delay on the pump motor OR get a smaller pump.

A/C units don't need much of the flow normally supplied to cool itself. Found this out once when my pump fried so I ended up hooking up a water hose up from the dock to cool the system. It of course ran constantly, but I was able to turn the flow down to about 1/3 of the pump's flow without losing A/C efficiency. Confirmed this with Marine Air in Florida too.

 

Our last boat (32' Wellcraft St Tropez) had a 12000 BTU Marine Airrrr unit that was able to be powered by our Honda 2000 inverter/generator. My buddies boat had a 10000 BTU Mermaid A/C unit and the same genny would NOT start his A/C.

Remember, it's not just the A/C unit starting but also the raw water pump at the same time.

You might want to temporarily disconnect the pump wiring to see if the A/C compressor will start with your genny. If it does (it will soon shut off since there is no cooling water) you might want to either put a time delay on the pump motor OR get a smaller pump.

A/C units don't need much of the flow normally supplied to cool itself. Found this out once when my pump fried so I ended up hooking up a water hose up from the dock to cool the system. It of course ran constantly, but I was able to turn the flow down to about 1/3 of the pump's flow without losing A/C efficiency. Confirmed this with Marine Air in Florida too.

Something to keep in mind if the above advice doesn't pan out. Some units will not even attempt to start if water flow is not proven so disconnecting the water pump may not assist your troubleshooting in this case.
~Ken

 

You'll need the EU3000 to successfully run the AC unit. I have one and run my 12,000 BTU AC on my fifth wheel with it. The 2000 won't handle the startup amperage and the circuit breaker will trip every time.

Besides, with the eco-throttle feature, the EU3000 will run 12+ hours on one tank of gas.

 

Yes, you can finesse starting current, but it's a bad idea to use a portable generator on-board so there's no point in detailing it. I do not wish to contribute to someone doing something unsafe.

Best regards,
Frank

 

Hey, I know what to do.

Get a cigarette lighter 12VDC adapter.

Make your own power cord with male plugs on both sides.

Plug the adapter in, plug the double male cored into the adapter and a 120V outlet AND plug in the Honda 2000i so the cigarette lighter adapter gives you that extra power to get over the hump.

****** Warning, I’m kidding!!!!!!!!!!!!!!! Do not do this. *****

 

I know this sounds obvious, but is the eco-throttle off on the generator? Make sure all other AC draws are off. (Water Heater, etc.) If it still doesn't work, then you might be outta luck. The good news is that if the generator was recently bought, you can probably return it.... or trade up. : )