Honda or Yamaha (2) 2000 Watt generators parallel together

I have l5,000 btu air conditioner on our rv. Went to Nascar race last week and saw alot of rvs with (2) 2000 watt generators parallel together. Talked to several people who were very pleased with the set up. Can run one just for lights etc. and start up second generator to power the air conditioner when needed. I forgot to ask the people I talked with if they had a 13.5 or a 15m btu. I talked to Honda and Yamaha directly and they will not guarantee that the generators can handle the amps needed to start the 15 m btu air conditioner. I'm hoping someone reading this forum might know or have the same situation. We are using a very noisy and heavy generator but wanting to change. Thanks!