Can My Generator Handle My Aircon?

[Gone2long]

We have a new, energy efficient, Carrier Optima air conditioner on our boat. The AC is a 230V, 495W unit, which, according to Carrier, draws only .5-2.15 Amps depending on usage.

We will soon be anchoring in various locations where no shore power will be available, so we are thinking about running the AC off our portable generator.

The generator is a "Promate 3,000" which outputs 2.8 KW of 230V power, which I assume, will supply about 12 Amps. The specs for the generator also show a "Surge Output" of 3.5 and a "Power Factor" of 1.0.

My question then is, will the generator adequately handle the load from the AC, and, if so, does anyone know how much fuel per hour we can expect to use running this system? The math seems to indicate that we should be fine, but I am wondering about the air conditioner's startup power surge and how that would affect the generator and the functioning/life of the AC.

[Sidney777]

The problem Might be at the Startup of AC. It takes more power. It may need too much power & AC might shut off your generator. If it does shut off at startup, there is a "hard start kit"you can buy that hooks up to AC or Fridge that makes it draw less power at startup. --someone on forum will know.. Just need a test run to see what happens ?

[a64pilot]

You should be fine as you have 7 times the generator output that the AC draws.
Curious, do you know the BTU of this 500W AC?

[Gone2long]

Originally Posted by a64pilot

You should be fine as you have 7 times the generator output that the AC draws.
Curious, do you know the BTU of this 500W AC?

Hi guy,

Always appreciate hearing from an experienced hand like yourself. Yeah, I figured the generator could handle the surge, but I didn't know what the 3.5 Surge Output # meant, so it got me wondering if the generator could handle the surge from the AC.

I have heard that an AC surge is 5-6 times the normal rate, which would mean an initial surge of 25 Amps or so. However, I have also read that this occurs only for milliseconds, so is usually not a problem for breakers and the like. Is this in line with your thinking?

As per your question: The AC is not rated in BTUs. It's rated in Kjs per hr = 5,000.

Whaddaya think?

G2L

[Gone2long]

Originally Posted by Sidney777

The problem Might be at the Startup of AC. It takes more power. It may need too much power & AC might shut off your generator. If it does shut off at startup, there is a "hard start kit"you can buy that hooks up to AC or Fridge that makes it draw less power at startup. --someone on forum will know.. Just need a test run to see what happens ?

Wanna find out more details before I try a test, and I am pretty sure that no such kit is available where I am, in the boonies of SE Asia.

Thanks, however, for the input.

G2L

[Sidney777]

My reply is from experience with a slightly larger new generator not running the AC while off of dock. My old gen did run it. (Much to my sweating chagrin) . By, the way. Startup kit may be in use more so in the boonies because of generator use. It is @12 in long & 3 in wide. (Not knowing if you need it) . Here is one brand of many. Supco. Spp8e ,about $30.

[autumnbreeze27]

I'd be really surprised if you have any issues running that AC with that generator.

[Gone2long]

Originally Posted by autumnbreeze27

I'd be really surprised if you have any issues running that AC with that generator.

Thanks. Got an idea about the gas I'd burn?

G2L

[Gone2long]

Originally Posted by Sidney777

My reply is from experience with a slightly larger new generator not running the AC while off of dock. My old gen did run it. (Much to my sweating chagrin) . By, the way. Startup kit may be in use more so in the boonies because of generator use. It is @12 in long & 3 in wide. (Not knowing if you need it) . Here is one brand of many. Supco. Spp8e ,about $30.

Got it, thanks. How much gas do you burn running the AC on the new gen?

G2L

[Captain Bill]

Originally Posted by a64pilot

You should be fine as you have 7 times the generator output that the AC draws.
Curious, do you know the BTU of this 500W AC?

KJ/Hour are almost the same as BTU/hour 5000 KJ/H =4739 BTU/H

[Gone2long]

Originally Posted by Captain Bill

KJ/Hour are almost the same as BTU/hour 5000 KJ/H =4739 BTU/H

Thanks, was wonderin : )

G2L

[transmitterdan]

It will run about 6-8 hours at that load with a full tank. Hard to be more specific because the AC probably is a variable load. That AC will only cool a very small cabin.

[StuM]

15 litre tank, 1.5 litres per hour @ 75% load, so 10 hours.

You don't say what, where or when you are sailing, but Transmitterdan is right, 5000 kJ/hr won't cool much.


Edit: Just saw your subsequent post where you say SE Asia. Don't expect to cool anything more than a small enclosed cabin and you will still be running the a/con on a very high duty cycle.

[a64pilot]

My little Honda EU2000 will easily start a 5000 BTU so I feel sure you will be OK.

[Delancey]

What the world needs, another person in the anchorage running their generator all night.