It will be more than a week before I can try switching the water heater.
This is the gen I bought.
Champion Power Equipment 73531i 2,000 Watt 4-Stroke Gas Powered Portable Inverter Generator (CARB Compliant)
Quiet, lightweight and portable; the Champion 2000 watt Inverter Generator provides clean, quiet power for campsites, RV's, cabins and other remote locations. 1700 watts Rated, 2000 watts Maximum output. Inverter Technology provides clean power (safe for sensitive electronics) and variable speed engine to reduce noise, conserve fuel and lengthen the life of the engine. Lightweight - only 48-pounds Quiet - only 53 Dba. Powered by Champion 80cc OHV engine designed specifically for the 2000 watt inverter generator will run 10 hours on a full tank of gas at 25% load. EPA/CARB approved for sale in 50 states. The Champion 2000 watt Inverter Generator is parallel ready, allowing you to stack two Champion 2000 watt generators and combine the output power into one outlet (need accessory parallel kit #73500i). Features fully enclosed durable housing with easy carry handle, 1 - 120V Duplex outlet (5-20R), 1-12V DC Outlet, Overload Protection, Low Oil Sensor and Economy Mode Switch. Includes: One bottle Engine Oil & US Forest Service approved Spark Arrestor. Dimensions: 21.5-inch (L) x 16.25-inch (W) x 18.25-inch (H). 2 Year Limited Warranty. Champion has the best Product Quality and Customer Service in the business. All Champion products are cover by our Lifetime Free Technical Support and 2 Year Limited Warranty.