How many watts are needed to start the aircon unit

This generator will run an a/c unit up to 13500 btus and is good for 2800 watts. This is a small generator, the nameplate rating numbers need to jive before overloading the energy supply.

the generator is not big enough to run what you want
it needs to be 3500w minimum or 4.5w to be safe
although it is stated at 2500 watts , in fact that is the peak load on electric motor start up and its continuous rating will be around 1.8 watts
all of this is clearly stated on the specs plate on the generator

You can check the AC unit, it will tell you how much electricity it needs. Likely 15 or 20 amps. That's about 1500 or 2000 watts. What does your generator supply?

you are missing the voltage supply here to get an definitive answer
for 240 volts drawing 4.8 amps the required wattage is 1152
for 120 volts the wattage is 576 watts
for 120 volts with a current of 900 watts , it equates to 7.5 amps
with 240 volts with a current of 1150 watts , it equates to 4.79 amps
so you can see the problem by not stating the supply voltage
get access to an cable clamp amp meter / watt meter from an electrician and read the current on starting the ac unit
if it exceeds 900 watts for 120 volts or 1150 for 240 volts , consider a bigger generator

http://cdn.powerequipment.honda.com/pe/pdf/manuals/31ZT7601.pdf

I would check spark arrester and clean it and the muffler first.lt could be the inverter unit. If you have a meter determine the output voltage, and freq. You would need a scope to look at waveform the repair should be lest to a repair center. suggest you call Honda for more guidance.
You could spend a lot of money on maybe parts./

Check for faulty low oil sending unit or oil level low or dirty oil (some generators have a fuel cut-out solenoid at the carb ). Key switch will override the low oil safety. Easy test, remove wire from oil sending unit. If unit runs, and oil has not been changed in a while, service engine and retest.

hmm.... try running it for a while with something plugged in that won't mind the voltage drop... like a light bulb..

Depends on wattage demand of ac unit. VXA=W 110x20amps=2,0200 Watts. A 2,00 watt generator is too small. Best go for a 3,kw genset. A 5 kw will leave you room to run appliances and the ac simultaneously., otherwise you will need to watch your margin usage. I think 4.5 kw gensets are also available. Happy trails.

most generators have a reset button. check your manual under the trouble shooter section good luck.

A: Running watts are the continuous watts needed to keep items running. Starting watts, are extra watts needed for two or three seconds to start motor-driven products like a refrigerator or AC unit.