What size generator would I need?

[INMIline]

I just want to run a deep freezer and furnace when I lose power. Will 4000 watts do it?

 

[dans4420]

look here Wattage Chart

 

[churchmouse]

Get a 5500 and know you have enough on hand. You can not run a full 4000 watts constantly. That is max or inrush wattage. Most good units will run 80% of Max in full load.
That's a mere 3200 watts.
A compressor will hit more than half that on start up depending on what size and load factors. A furnace runs on a 30 amp circuit an can draw some currant when the blower motor comes from locked rotor (static) and runs up to speed. If both try and start at the same time you could in theory hit the limit.
Get a 5500. Have enough.

 

[CountryBoy19]

I just want to run a deep freezer and furnace when I lose power. Will 4000 watts do it?

You need to define "Furnace" much better.

Furnace can mean a gas furnace that just needs power to kick it on and run the blower. Or it can mean electric heating element type furnace that takes 20 kw to run. My all-electric "furnace" has a 19 kw heating element in it. I would need a 20 kw generator to run it. For comparison sake, a gas furnace that just needs electricity for the blower may only consume 2-500 watts.

Freezer you're looking at 100-400 watts most likely, maybe about 1kw max for startup draw.

If your furnace is gas I would check out the power consumption to size a genny properly. The manufacturer may even have that info on hand already.

For the freezer I recommend you get a kil-a-watt meter ($20 at Menards) and see what your freezer actually draws. The kil-a-watt won't tell you startup current but a good rule of thumb is that it usually doesn't exceed 3 times the running current. The kil-a-watt is a very useful tool, you can even use it to track how much total power something consumes over time.

A small 2kw genny might be plenty to run things if your furnace is gas. If it's electric you're looking at a very large unit that will guzzle gas.


FWIW, my electric furnace hasn't been used since my first winter here. I installed a wood-burner and for the last 3 years I've been burning wood for heat because electric heat is really, really expensive.

 

[Iroquois]

Standard home wiring these days usually means 20 amps per circuit....using Ohms law a 4000 watt generator will put out 33 amps (4000W /120v = 33.3a) Split on two circuits
you get 16.6 amps. Probably enough.....but if you have a choice get a 5000watt unit.
You never know when you might need to add something else. It's nice to already have that option.

 

[PistolBob]

I just want to run a deep freezer and furnace when I lose power. Will 4000 watts do it?

No.

But I say that without knowing what you are calling a furnace. Is it natural gas , heating oil, or is it electric? What kind of current does your blower motor pull? Are you going to try and heat the whole house or just a couple of rooms? a 4K watt genset will cover a couple of 15A circuits for awhile. If you are thinking about running it for days on end then you might be in bad shape by the second or third day.

4KW is not really very big

 

[churchmouse]

Standard home wiring these days usually means 20 amps per circuit....using Ohms law a 4000 watt generator will put out 33 amps (4000W /120v = 33.3a) Split on two circuits
you get 16.6 amps. Probably enough.....but if you have a choice get a 5000watt unit.
You never know when you might need to add something else. It's nice to already have that option.

Your math is correct but you are thinking the unit will deliver at rating plate but they will not.

Again...80% of rated delivery not a full 4000 watts. That is in rush or peak. Lesser units will run at 75% of rating on continuous delivery.
My 2K unit will not support both refrigerator and furnace (gas) if both cycle at the same time. It loads the unit down very hard and is harder on the appliances you are attempting to operate. A 4000 will do what he is asking of it but get something with a little room to breath. They only rev up to the load requirements if they are running properly.

Pistol bob is correct...a 4K will reliably deliver 3.2K at 80% but a lesser one will level off around 3K. That is running it's balls off. Opps, I said ball's

 

[catfishjn69]

From what I have read I think you would want more then 4000 Wat's probably closer to 6000 watts

 

[10-32]

I just want to run a deep freezer and furnace when I lose power. Will 4000 watts do it?

I'm assuming that your talking about losing power in the winter since you mentioned running your furnace. If that's the case, don't waste gas in a generator running your deep freezer. Get a couple of totes with snap on lids and set the frozen goods outside the freezing weather. If you don't want to do the tote thing, pull out the deep freeze and look at the watt usage on the tag. Watts x 3 = Starting power. Do the same with your furnace then add the two.

4000 watts to run your furnace, as others have said, maybe. Take a look in your breaker box. If the breaker is only a 20 or 25 amp, you should be good to go. If it's a 30 amp or higher, a Honda or Generac might do it. I wouldn't try it using some off brand or anything you picked up at Harbor Freight.

As others have said, look into a 5000 - 6000 watt generator. You can pick up a decent one around 550 depending on the brand.

In my case, I own a 5000 rms/6250 peak generator. My furnace is on a 20amp breaker and the fridge is on 15 amp breaker by it self. 35 amp x 120 Volts = 4200 watts. I feel more than running both at once with my generator. I think running only 4000 watts you could only run one thing at a time.

I should also ask, the 4000 watts, is that peak/surge or is that continuous?

 

[10-32]

look here Wattage Chart

That chart says to take the watts x 2 for start up power. Most of the well known manufactures of generators say Watts x 3 = Start up power.

It also uses approximate watt values. Guessing is a good way cause yourself all kinds of problem. You should always check the device for the watts being used.

 

[Meister]

I have a troy built. It's the 6000/8250 unit. I keep it attached to my trailer. It will run pretty much anything in the house if I choose to. Loud though, Very loud.

 

[churchmouse]

I have a troy built. It's the 6000/8250 unit. I keep it attached to my trailer. It will run pretty much anything in the house if I choose to. Loud though, Very loud.

We are experimenting in exhaust sound suppression. No tax stamp required at this time for such things.

 

[nate1865]

I have a 3500W/4000W generator that easily powers my furnace fan and refrigerator simultaneously along with several other circuits. The furnace is natural gas with an electric blower.

 

[churchmouse]

I have a 3500W/4000W generator that easily powers my furnace fan and refrigerator simultaneously along with several other circuits. The furnace is natural gas with an electric blower.

You may be in for a surprise one day. Just saying.
Have you measured the total draw on the "Several other circuits"
Do the math on 3500 watts. What is the total amp draw at that figure. You may be harming some appliances with a low voltage condition.
It is your stuff so do as you will but 3500 W will not "Easily" provide that much power.

 

[Icarry2]

This topic has been discussed exstensively on other threads. The search function can help you locate the information.

As for a few key points.

Back feeding is bad.

A generator has two "legs", they must stay balanced or you shorten the life of the unit.

Always over size, in rush on a motor is much higher than when it runs.

Maintain your unit, start it once a month even no matter what.

Keep the fuel treated, I use Seafoam.

Rotate your stored fuel and keep it treated.

Read, learn, practice running your house on the genny..

And most importantly, if you have no idea what your doing installing one or hooking up a load center pay a professional.. The whole "I thought I knew what I was doing" to your insurance agent after your house burns down from an electrical fire probably won't do it..

Help?

TJ

 

[bwframe]

I'm working at getting the stuff together to run my generator. This has been great advice. Thank you!

Any ideas concerning stored gas as far as summer blend vs winter blend?

 

[CountryBoy19]

Back feeding is bad.

Not necessarily. "back-feeding" means different things to different people. Technically, the "lock-out" devices are enably backfeeding to be safe. So it's not necessarily bad, it's just potentially bad depending on how it is done. Although there is some risk of smoking your generator if you leave the main on and run your generator and the power comes back on, the real risk is electrocution. If you leave the main on and run a generator you can fry a lineman working on the lines. Or, if you use a double-male plug, there is risk that it can come un-plugged and electrocute you.

Any ideas concerning stored gas as far as summer blend vs winter blend?

Summer blend is less volatile. Which means in warmer weather it will build less pressure in your containers and you will lose less volatile chemicals to evaporation. However, being less volatile means that in extreme cold weather you may have trouble getting it to light off in a cold engine.

I don't see the latter as being too much of a problem so I recommened storing summer blend. That being said, I don't pass up the oppurtunity on cheap gas even if it's in winter. It will all store, it just won't all be ideal.

 

[Icarry2]

Not necessarily. "back-feeding" means different things to different people.

Agreed. I was referring to back feeding the grid. You make very good points.

I used to "back feed" my house from my garage where my generator was protected from weather by an over hang and it kept the noise level in the house down. But the wire was large enough and the incoming main from the power company which was in the house was open and locked.

On a side note,

I have also seen idiots back feed a 6,500 Watt generator into a dryer outlet rated at only 20 amps. Took out the dryer socket, the wiring, the breaker, the distribution panel and half the house. Probably hurt the generator and shortened the life of some other appliances and such in the house. Whole deal cost the owner about $40k because he thougth he knew what he was doing.. Turns out he didn't..

I have also witnessed wires being cut and a pole being cut down due to a guy back feeding the grid that just about killed a lineman. Supervisor said take down his pole and he can pay us $3,500 to put up a new one.

I guess my point still stands, if you have no idea what your doing call a professional.

I have never done any research on the difference between summer and winter gasoline but I have heard that there is more butane in winter fuel. Be interesting to find out more.

OP, if you need assistance I am sure that there are many on here who can help. Feel free to PM me if you cant find the answers to your questions but like I mentioned, most have already been answered in other threads that is why I mentioned the search function.

TJ

 

[Sniper 79]

I just picked up a 5500/6500 from Harbor Freight for a back up along with a cheap sump pump. Hope to never need the stuff but with a new full finished basement it scares me not to have anything on hand. Chalk it up to insurance I guess. I want to get it wired up so all I have to do is plu into the house and flip a switch.

 

[columbusprepper]

i use to service titan generators for a construction company. They are really loud and require gas or diesel (or karosine). There are TONS of YT videos on how to make a solar generator. Few solar panels, batteries, power converter, power protection and you got free energy!
It's quiet, safe, and discrete.