Ok, so I have been reading posts about people who changed out their fridges to residential ones. I too did this a couple years ago and the fridge always worked fine on my modified wave inverter. However recently it has determined that it does not like the modified wave inverter and had let me know by putting out a little smoke smell when on it. So when looking at other posts I see a lot of us are trying the same thing, but I could not find any results specific to my situation.I have a Whirlpool 22 CU Ft. fridge. What I have learned online is that it draws 6.5 amps and times that by 120 = 780 watts times that by 3 for peak surge of 2340 watts. So to cover the peak I have found most 1200 watt pure sine inverters have peak surge of about 2400 to 2500 watts. I have 4 - 6 volt batteries that my current inverter/charger runs on. I would like to dedicate a new pure sine inverter to the fridge and have it powered by the same battery bank. Can it be as simple as just hooking it up? Is there any issue with the fridge running constantly on the inverter only? Is there anything else I should concern myself with?Thanks,

If I had to guess, the capacitor for your fridge compressor is shot (and what you smell is the electrolyte boiling away), probably from dealing with the ripple of a MSW inverter. A PSW inverter might not solve the problem at this point. Electrically, there's no reason I can think of not to connect another inverter to the battery bank. 6v golf-car batteries are built for heavy loads, so as long as your wiring and charging can handle it - go for it.

You are in luck as I recently installed a 21 cu ft Whirlpool refer here and the 6.5 is the start up amps. I did a test run on battery power (500 AH) with my 1000W PSW inverter and at the start with 13.2V my inverter was drawing 7.5 Amps as the battery voltage dropped the amps increased to 8.3 at 12.4 V. At one point the amps jumped up to 22 and I'm wondering what's going wrong:h ... it was heating the ice tray to harvest the ice. :B So running it's drawing 100 Watts and even times 4 for startup... a 500W inverter would do. I wanted to power my Sat receiver and a DVR too so I went with a 1000W. I installed it's own battery bank mainly to get more charging amps while running the generator. I looked into upgrading my inverter to a 3000W PSW but between the price and the control cable not having enough wires I could add a separate system for less money.Even figuring a 75% duty cycle (18 hours run time) that's aprox 144 AH/day so almost two days before needing to recharge. I tried setting the inverter to power down when not needed, but it will not power back up so when waiting to go to work it draws 0.7 amp. I left the door open so I could see how many amps it took to start the compressor... 32 very briefly so a 500W PSW inverter would be big enough.

I would suggest checking the controller board of the fridge, to be sure you didn't fry the capacitors.I also run a residential fridge off a full sine inverter. No reason you can't just plug the new one into your existing batteries.Jose

:S Only took me a month to realize I had all the information to figure the duty cycle of this refer as I posted this in my DIY post:"This EnergyStar Whirpool 21 CuFt Refer has a energy guide of $44/year and 410,000 kWh/year or 1,123 W/day or 94 Amps/day... So out of my 500 AH battery bank I should be able to go two days before getting to 50% and needing to recharge. $44/year is 12 cents a day... It's amazing how energy efficient they have gotten these things."1,123W/day divided by 100W running equals 11.2 hours/day or a 47% duty cycle.

Those EPA labels makes a lot of assumptions, like the fridge is installed on a north facing wall, with an average ambient temperature of 68 degrees, door is only opened once every 12 hrs, ice maker is turned off, etc etc.

Fridge and inverter, can I do this? | Good Sam Community

20 Replies

Freightguy
Explorer
Aug 21, 2015
Bill.Satellite wrote:
I did the same thing. While it was likely unnecessary, I replaced an old Heart Interface 2000 MSW with a 3000 watt PSW. The higher 300 amp battery charger was one reason but the PSW was very attractive. Now, all of my clocks keep time and by batteries recharge faster.

That is interesting that the higher charger was attractive to you. I use my power management to reduce the amount of charge to the lowest I can get it and still have the functionality. I credit the low and slow charge rate to my house batteries lasting over 8 years.
Bill_Satellite
Explorer II
Aug 21, 2015
I did the same thing. While it was likely unnecessary, I replaced an old Heart Interface 2000 MSW with a 3000 watt PSW. The higher 300 amp battery charger was one reason but the PSW was very attractive. Now, all of my clocks keep time and by batteries recharge faster.
lwasouth
Explorer
Aug 21, 2015
Freightguy

Yes, I replaced the existing, figured that all things would be better on the sine wave inverter. Otherwise I would have had to isolate the refrig circuit and put it on an inverter by its self. All the inverter- only units I looked at had no remotes to turn them on or off.
westend
Explorer
Aug 20, 2015
Iwasouth,
Nice work on the Whirlpool installation. It looks like the factory put it in.

You guys can discuss the details. I'd just say again, get more inverter than what you think you need and use large cables between batteries and inverter. If your battery banks can support it, a large inverter will do more for you than just power the fridge. These newer quality PS inverters are very efficient, using less than an amp in standby or have an auto shutdown feature. Paired with solar, it makes for a great system.
Freightguy
Explorer
Aug 20, 2015
lwasouth wrote:
Freightguy

I would assume your generator and shore power both come in to your transfer switch. One 30amp lead from the transfer switch goes to the AC HOT "IN" on your existing inverter. The AC HOT "OUT
" goes from your inverter to a 30 amp breaker on your main 120 volt AC panel. Still allows your 50 amp from generator or shore power to operate in your coach. My previous modified sine wave unit was a Dimensions 2000 Watt. The new one is a Maxium 2812 PSW. Biggest problem to overcome is trying to route the cables for the remote and battery temperature sensors.(Most coach manufacturers bury them somewhere in side the floor during construction) This was eliminated by using the old inverter's cables and installing new connectors on them to match new system We live near Crystal River Florida

Ok so you did not add an independent inverter for the fridge right? You replaced the inverter you had?
lwasouth
Explorer
Aug 20, 2015
Freightguy

I would assume your generator and shore power both come in to your transfer switch. One 30amp lead from the transfer switch goes to the AC HOT "IN" on your existing inverter. The AC HOT "OUT
" goes from your inverter to a 30 amp breaker on your main 120 volt AC panel. Still allows your 50 amp from generator or shore power to operate in your coach. My previous modified sine wave unit was a Dimensions 2000 Watt. The new one is a Maxium 2812 PSW. Biggest problem to overcome is trying to route the cables for the remote and battery temperature sensors.(Most coach manufacturers bury them somewhere in side the floor during construction) This was eliminated by using the old inverter's cables and installing new connectors on them to match new system We live near Crystal River Florida
Freightguy
Explorer
Aug 20, 2015
Nice work,
lwasouth
Explorer
Aug 20, 2015
Here is my photo....i hope
lwasouth
Explorer
Aug 20, 2015
I just finished the install of a 21.7 cuft whirlpool Frig and a 2812 Maxiun PSW inverter in my 05 Itasca Horizon. The frig was 65.5/8" tall (With Wheels removed) 32 5/8" Wide. I created my opening 66" tall and 35 3/4" Wide. I fabricated 12" steel "L" brackets that screwed to the rear edge of the frig on each side, that screwed to existing steel mounting brackets attached to the coach wall.
Freightguy
Explorer
Aug 20, 2015
lwasouth wrote:
I just finished the install of a 21.7 cuft whirlpool Frig and a 2812 Maxiun PSW inverter in my 05 Itasca Horizon. The frig was 65.5/8" tall (With Wheels removed) 32 5/8" Wide. I created my opening 66" tall and 35 3/4" Wide. I fabricated 12" steel "L" brackets that screwed to the rear edge of the frig on each side, that screwed to existing steel mounting brackets attached to the coach wall.

I would be interested on your inverter setup. Wiring, auto transfer switch location and stuff like that?