OT Running furnace and frig off a Power Inverter

I need some enlightenment.

I bought a 2000 watt continuous/4000 watt peak inverter and was wondering if the 120 volt Modified sine wave will do any harm to my Mid 1990’s York Furnace or new Whirlpool Refrigerator? I have read that I could fry the circuit board of the furnace and do harm to the electronics of the refrigerator.

I don’t see how the electronics on the furnace would get harmed, because I believe the 120 volt AC is run through a transformer to change it to 24 volts. The only items running on 120 volt AC are the fan motors and ceramic heater to start the burners. The frig I am not so sure about.

I am not worrying about drawing the battery down because I have a 63 amp alternator run by a 6 ½ HP engine to charge it. I mounted everything on a cart, so it’s very mobile.

This is only going to be used in emergencies and to charge batteries on tractors, truck, or cars that are not near the buildings.

I guess it's not that off topic, since I did say I would use it to charge the tractor batteries.

Forgot to mention that I use only extension cords to run these and make sure there is no backfeed through the electric panel. The frig. was easy,just unplug and plug into extension cord, but the furnace needed a 3 way switch to make sure the positive, neutral and ground was isolated.

I run one in my truck. I run a fridge with no issues. I read those warnings in the om to, but I use it for everything, microwave, fridge charging phones and cordless drills. Everything works good accept for electric blankets. You plug those in and they instantly start on fire. If you get the ones with the digital controls they just don't work, but the ones with the dial controls will be in flames in seconds. Don't know why and those are the only things that do that. Used electric heaters just fine too.

You run your computer on one when the lights go out so why would it hurt the one in other things.
Walt

We do not have mains power on the farm so I have set up a solar system. It has 24V panels, 400 amp hour 24V batteries, 24V pure sine wave 1200 watt inverter and CTEK 24V charges run from Honda 20i generator.

All appliances are 240V (standard here). We run a standard domestic fridge and small freezer, plus lights, TV etc. It will not run a standard washing machine (surge load is too big)—had to buy an 'inverter' washing machine that has electronics to convert AC to DC for soft start. We can also run split 'inverter' air conditioners, though we usually run them direct from the generator. With 1200W (surge to 2000W), we have to be careful with what we have on with the fridge and freezer always getting priority.

It is not as good as mains power, but it is a lot better than no power.

honestly, i would be surprised if it ran both.maybe ,look at the rating plates on your appliances. if they have running loads listed in amps instead of watts,simply multi ply the amps X voltage (120) to get watts. keep in mind that the inverter itself will be a load also. be very certain to keep polarity correct, add disconnects as needed because you most likely dont want power feeding back into your inverter. the main problem with these type setups is they draw power even when furnace or whatever is off,through the inverter.without some type of maintainer running constantly to run inverter and charge battery,the battery will go dead over time. my opinion of course, but if this system was just for occasional/standby use,a small genset would serve you better. IF you were designing a system for off grid use using inverters and things,you would be much better served with a straight 12 volt system,appliances etc. that way you wouldnt have the constant loads you would have inverting/converting power.anothe roption would be to have a small 12 refridge,and move your food in there during power outages.furnace could something like propane stove or the like that needs no external power.my opinion of course,but you normally do not use a inverter as a power source where power to run a alternative is available .your burning gas to run a alternator that needs power to just turn on,then your hooking it to a inverter that sometimes uses more enrgy than it makes,then your running the most ineffecient systems off that.triple waste of power.

How long do you think you can suck 100 amps out a 12v battery? 100a x 12 v = 1200 watts. A frig will require a large amount of power to start. A furnace's biggest load is the fan motor. The modern hi-tech furnaces may not like the inverter voltage. If you have an old oil furnace, it has two motors, blower and gun.

I wouldn't want to stay warm with battery backup.

Personally, I think it's a pipe dream.

Post back if it works.

I think you would be better off with an RV genny. They are quiet, can get 30 amps out of the RV plug. That might work much better and run both furnace and frig providing the furnace likes the wave put out by the genny.

lots of luck

Your modern hi-tech stuff needs pure 60 cycles and you will have all kinds of fun repairing.

As George pointed out. You are finished before you start with little 63 amp alternator and an inverter that draws 500-1000 amps.
Instead of trying to save money and having less performance after spending more money than doing it right I"m the first place.
Should have just bought a 2000W inverter from Walmart and an ordinary booster battery charger .
Your current set up is good for about 10 minutes before tripping off line.

Yup, your input doesn't have a snowball's chance of keeping up with your output.

At 2000W, your inverter will be drawing at least 167 Amps. 63 Amps in vs. 167 Amps out = 104 Amps shortage.

Also keep in mind that a 63 Amp alternator is not designed to output 63 Amps running a fridge or furnace during a sustained power outage. It's only meant to run like that for a few minutes to top off the car battery after a start.

...and before you say something about how many cold cranking Amps your battery has, forget it. CCA rating is only meant to be sustained for a few seconds while you start the car, not running a fridge or furnace during a sustained power outage.

Same goes for that inverter. Even though it says 2000W continuous it is likely not capable of sustaining 2000W indefinitely.

You've got a good idea there for cheap electrical power, just not on the scale you expect to be using it. Charging tractor batteries, running tools and lights in a remote shed.