The generator thread has me thinking. I would like to be able to run my well pump (220), hot water heater, and maybe a refridgerator if we have blackouts again. I have no clue what I need. Any ideas as tom size and brand. I know nothing about this subject. They don't have to run all at once. I can heat water and run the well separate. By that I mean I coud heat water, shut off the heater and take a hot shower while the pump kicks on.

How big is the well pump?

I’d look at a dual fuel option, propane/natural gas is easier to store the gas or diesel

I think it's 1HP. I was going to go with a dual fuel. I've got a 250 gallon propane tank for the house I could hook it up to if I want.

Contact an electrician and get them to figure what you need.

Is your water heater electric or propane? If electric plus startup of well motor and fridge compressor if they happen at the same time you probs need 7 or 8 kW. Water heater alone could be as much as 5 kW if is electric and depending on size. If you strategically operate breakers so things run separately could probs get away with 5 kW or maybe less depending on water heater size.

I use my welding machine. Wired in a plug and a block out so I can hook up a cord and power my whole house.

Yes the water heater is electric. I would run them separately and rotate times they were on. I hate that I had a nice Miller Bobcat welder that I sold when I got divorced. Those things are out of sight expensive now.

When you get this figured out, tell us what worked. My neighbor and I both wanted a small back up generator (to back up the Generac) for just the well pump, in the event we ran low on propane again. Then we realized it took 220.

We are all electric, 2500 sq ft. I use a little 5,000 watt portable generator through an outdoor plug to back feed my 200 amp main panel with 240v. You need a simple interlock bracket to be safe and legal. It is really nice to have all of my lights and outlets working as normal! A big whole house standby generator would be a heck of a lot more convenient, but a smaller generator makes whatever amount of fuel that I can store, last more days. Do the math on your fuel consumption before making decisions. Inverter based generators change RPM with load and that really helps with fuels consumption.

MY approach is to be sure that I can stand on my own for at least a couple of weeks. Much longer if I cut back to minimum and use my little Honda 2000 for my base loads. Doing it over, I would go with two 3500 or 4500 watt generators that could be run in parallel only as needed. That provides redundancy and additional flexibility.

My “base loads” that I want to always be on, are two side by side refrigerators, a chest freezer, and an aerobic septic system. Yes, either the upper or lower oven can be used, but not together. I can run one or two stove top burners but not with the microwave oven and coffee maker. I can't run the 5000 watt electric dryer or central A/C. It does start my 1.5 HP lake water pump as long as other major loads are off during the pump start.

I installed a simple switch to drop my 240v 4500 watt water heater to 120v, so it only draws 1100 watts. Yes, it takes longer to heat the 50 gallons, but I have hot water. I have a diagram of how to do it if you are interested.

Marc

Figure out the total watts of all items you want to run. Ohm's law applies, meaning you need any two of the three ( volts, watts, amps) to calculate the third. So if you have voltage and amp draw requirements you can easily convert to watts. Search for an Ohm's Law online calculator, there are many out there.

When you have the total load choose a generator that has a running wattage rating of roughly twice your calculated total. Why twice the amount of watts? Because all generator spec's are given at 50% load. Yes, you can tax the generator more by running at a higher percentage load, all the way up to the unit's advertised running load rating (in theory) but run time will suffer proportionately as a result. And since you have at least one item that needs 220v, you'll need to choose a generator that outputs 220v, most generators over 5k watts will output 220 and 120v.

After snommagaden I put in a generator lock out on my breaker panel, put through wall and outdoor plug, built a box and input the Harbor Freight large Predator generator with battery push button start. Easy to flip off breakers of chosen items not necesarily needed during outage. My thoughts were just needing to get through at least 5 days to a couple of weeks and I keep enough gas on hand (rotoate into vehicles about every 6 weeks). When I put cost to it vs dual fuel and or a Generac system, I'm good with the all in of around $1100 (includes electrical work) catching the generator on sale and with a coupon. Gas heat/water and all else electric. I do still need to add a solar charger to my geni battery instead of maintainer.

Found this online calculator to that can help - https://www.generatorszone.com/generator-wattage-calculator/

And two other sites you might want to read up on the info provided:

Run Time Cal

Consumption

I have one of these and it is enough to run the essentials and more if you work it right.

For example, we were without power for 8 days back in 2023 after a tornado. This would run the A/C for a while, then we would shut it off and let the fridge and freezers run for a while and catch up. Then we would run the A/C for a while, then shut it down and turn the water heater on for a while. The WIFI and TV stayed on the whole time, not much draw there.

That generator could probably handle most of that continuously, but start up draw was pretty hard with that much of a load.

https://factorypure.com/products/cummins

V x A = W

Look at the motor and see how many fla (full load amp) it pulls then multiply that by 220. That will tell you how many watts it needs for well pump. You can do this for each item you want to run. Just multiply volts time amps.

I’d say you would be good with 12k watts. You might get buy with 6k, but that pump pulls hard though on start up 4-6k watts.

Dual fuel gens capacity are often derated when operatong on propane. Just FYI.

I have a whole house generator and I'm wired up so the water heater operates on 120V when the generator is running and it works great. The wife and I can both shower before bed and the water will be at a normal temperature by the time we get up in the morning. Normally on 240 volts, the water heater would pull about 20 amps from both legs. Running on 120, it only pulls about 10 amps from one leg. My dish washer and cloths washer are intentionally on the opposite leg.

That, along with a soft start for the AC/Heat pump compressor, lets us operate normally on the generator, with the exception of electric cloths dryer. Due to the starting inrush of the dryer, we need to make sure the HAVA compressor is not running when we start the dryer. Once the dryer is spinning, the HVAC compress can start and run normally.