What size Gen do I really need?

[Kygene]

Hi, so I’m shopping for a home standby generator. I know the real answer is to get the actual data plate information however i just want to know without doing all of that what to believe. Last year when the power went out for a couple of days I hardwired a 6000kw running watt generator to my 200amp panel. This ran my 3 ton heat pump in cooling, two refrigerators, a deep freezer, two TVs and what ever lights I wanted. Never bogged down when the HVAC kicked on. When I go to generator sites like Generac and put in even less info into the generator sizing app it’s telling me I need at least a 6,000w almost double what actually worked. Am I missing something? Are they trying to sell me more then what I need or are they just protecting themselves from unknowns? Thanks in advance.

 

[davesparks]

Presably you mean 6000W or 6kW.

How long did the 6kW run for? You will find that the calculator you are using will be adding all the loads up without applying diversity, which gives a worst case scenario.
Also it may be considering run time into the equation, if it is trying to come up with a generator which will run for 24hrs on a single tank of fuel it may produce a bigger size.

 

[Kygene]

Presably you mean 6000W or 6kW.

How long did the 6kW run for? You will find that the calculator you are using will be adding all the loads up without applying diversity, which gives a worst case scenario.
Also it may be considering run time into the equation, if it is trying to come up with a generator which will run for 24hrs on a single tank of fuel it may produce a bigger size.

It’s 6000W. I can’t find a way to edit it. It ran on gasoline non stop for 72 hours straight. It Was only stopped every 8 hours to refill the gas tank. The bckup I’m looking at are rated to run at the specified watts running full load on natural gas. I personally feel a 13kw generac with a whole house 200amp transfer switch that is the same as my breaker panel would do the trick. Thanks for your advice.