104V is heading real close to about as low as I would push it. That said, what is the nameplate rating on the genny? 3500watts, 5500watts, or ? What is the running amp draw on the compressor? The temporary loss you saw on the meter was something know as Full Load Amperage, sometimes appearing as "FLA" on a motor nameplate. This is the temporary, and exponentially higher amperage load of getting the motor from a dead stop to full speed. It is totally normal. My guess is that running the genny anywhere close to full capacity, say 80% or so, is going to get you well below the 102 threshold, and into potential damage to any connected loads. From my experience, when it comes to low supplied voltage, the very first thing to take the hit is electronics, and in the case of RVs, it's typically the control board that run the appliances.