Inverter problems with fridge

[matthews2001]

Ok, going on 2 years now I have inverter problems.

3000w WZRELB from Amazon ($300) high efficiency. I want 3000 to run my microwave.

4 new 6 volt trojans.

energy star full size fridge from HD. 4 years old

No longer runs off inverter, inverter alarm goes off, so stop at autozone grab a low efficiency $100 inverter (200 or 300 watt), fridge runs.

Replace high efficiency inverter, same problem.

BTW the cheap inverter WONT charge my laptop but the high e one will.

House batteries always charged, cables to inverter from battery are from the chair lift I removed hugh wires, Disconnected and cleaned all ground connections. Any ideas? Running 2 inverters now!

ONLY FUNNY THING is last year I noticed I had refrig 110v outlet wired backwards so hot was neutral but refrig didn't care and ran 2 years like this, nor does it care it is now for a year hooked up correctly.

AND not to confuse anyone but did anyone ever turn off auto defrost to save electricity? It sucks power but only for like 10 minutes twice a day

Thanks!

 

[TheHubbardBus]

Is it accurate to say that one day the fridge was working, the next it wasn't, and nothing about your electrical system was changed in-between? Or did something (anything) change?

Are you saying the fridge is the only load being powered by the inverter when it fails? And if so, are you absolutely, positively sure that's the case?

Have you confirmed the inverter is powering other high-draw items sans the fridge? Does the microwave work?

 

[matthews2001]

Yes nothing else is on the inverter. I used to have the microwave on the inverter but 5 minutes use dropped both dc and ac voltages so it shut off. Note the wires to the inverter are the hugh ones from the previous handicap lift. the ends of the wires and ground have all been thoroughly checked and cleaned.

Some kind of gremlin here. I have heard using the Micro can discharge the batteries at too fast a rate so I just use the generator when I microwave.

But the perplexing issue is newish refrig only runs on the $100 low efficiency inverter, not the true sign wave inverter.

 

[TheHubbardBus]

Yes nothing else is on the inverter. I used to have the microwave on the inverter but 5 minutes use dropped both dc and ac voltages so it shut off.

OK, so we know that the only thing drawing power from your inverter / battery bank combo is the refrigerator. Put a pin in that.

Next Qs:

1) What, if anything, is drawing power directly from the battery bank (DC loads)? Can you or have you eliminated any DC loads when attempting to test the fridge? Basically what I'm getting at is: Are you absolutely, positively sure nothing is drawing power from your system - DC or AC - but the fridge?

2) Does the fridge fail in the way the microwave did (running until voltage drops)? Or does it simply not power up at all?

3) You still haven't answered affirmative that nothing changed between the time the fridge worked and now when it doesn't. But you say you have a new battery bank. Did the fridge work until you changed out the bank and then not work?

4) If nothing else is on the inverter and you stopped using the microwave, is it fair to say that it's possible you can't power any AC load right now, or maybe any large AC load? Have you tested it with other AC loads other than the fridge? If not, can you?

 

[matthews2001]

I like all the questions make me think...

1. ONLY frig is on the inverter. Other loads on dc are lights, two usb chargers for phones and a couple dc small fans

2. fridge ran on hi efficiency inverter 2 years, now only runs on cheap low e inverter, On hi e inverter a red lite and beeping come on.

3. Batteries are same for 4 years I just called them new, sorry

4. I have not tried any other high power loads, I can try a 1500 w heater but wont be at bus for 3 weeks.



Regarding me mis wiring the outlet that the fridge ran on for 2 years, hot was neutral etc, on the same outlet I had my gas stove plugged in which had a fan and ignition. The stove and frig stopped working, I investigated noticied the reverse AC wiring (which worked fine for 2 years) and when correct wired gas stove is kaput (so I light it now with a lighter), no longer plugged in and high e inverter wont run refrig, Being in Alaska I just bought a cheap inverter and avoided food spoilage, then replaced the expensiver inverter (which had actual burnt capacitors inside) a month later and it wont run frig either!!

 

[DeMac]

Missing a pita

These are BeNimble questions. ghosted us 12/21. (I hope he is well).

In his custom fridge thread, he discussed the different compressor types used in refrigerators. Both 12v & 120v, with & w/o inversion. The whole thread is quite entertaining & educational.

BeNimble's Custom Refrigerator

Within the thread above, you may find an angle of investigative insight regarding the inverter type, as paired with the fridge's compressor. Something cyclical?

Happy Hunting.



EDIT: matthews2001 & TheHubbardBus (next post) mentions capacitors. That is the load I wonder about, but inside of the fridge. Minimum compressor startup power. One inverter vs another, also one compressor vs another (now, after long term use).

 

[TheHubbardBus]

Regarding me mis wiring the outlet that the fridge ran on for 2 years, hot was neutral etc, on the same outlet I had my gas stove plugged in which had a fan and ignition. The stove and frig stopped working, I investigated noticied the reverse AC wiring (which worked fine for 2 years) and when correct wired gas stove is kaput (so I light it now with a lighter), no longer plugged in and high e inverter wont run refrig

So tell me if I have this right...

For 2 years you run this refrigerator, and another AC appliance (the stove), off the same outlet, powered by the same (expensive / high efficiency) inverter, from the same battery bank, and they both work fine. Then you discover the outlet is wired incorrectly, so you re-wire it, and immediately thereafter both appliances stop working. Is this correct?

If so, I'm pretty sure it's one of two things (or maybe both). Either you didn't wire things correctly when you 'fixed' the outlet, and/or you damaged the inverter in the process.

Being in Alaska I just bought a cheap inverter and avoided food spoilage, then replaced the expensiver inverter (which had actual burnt capacitors inside) a month later and it wont run frig either!!

This is becoming a bit confusing. So now you're saying you replaced the inverter after the fridge (and apparently the stove too) stopped working, and found out it was damaged. Then you replaced it and the new one worked (aka ran the fridge) for another month before also failing? Does it have burned out caps too? Was the rewiring done before, after, or in-between you replaced it?

 

[matthews2001]

I discovered mis wiring AFTER stove stopped working and expensive inverter wouldnt operate fridge anymore. This inverter would operate TV still.

I fixed miswiring, stove electric no longer works and just fridge wont run on inverter.

So I buy a cheap inverter and it runs fridge.

Neither inverter low e cheap one or replacement expensive one has failed again, only the expensive sine wave one wont run the fridge, just goes into red lite alarm mode.

I disassemble expensive inverter and at least one capacitor is burned out.

I purchase a new same expensive inverter and have it shipped to AK and it wont power the fridge. ONLY the cheap inverter will power it.

On shore power stove wont work but I havenet tried to trouble shoot that as a lighter works fine.

 

[TheHubbardBus]

Neither inverter low e cheap one or replacement expensive one has failed again, only the expensive sine wave one wont run the fridge, just goes into red lite alarm mode.

What does your manual say about 'red lite alarm mode'? What exactly is that indicating?

 

[Rucker]

<snip>

Neither inverter low e cheap one or replacement expensive one has failed again, only the expensive sine wave one wont run the fridge, just goes into red lite alarm mode.

I disassemble expensive inverter and at least one capacitor is burned out.

I purchase a new same expensive inverter and have it shipped to AK and it wont power the fridge. ONLY the cheap inverter will power it.

<snip>

I agree there's a lot going on in this thread. Capacitor fix is a big clue, my opinion. You state in another post "I discovered mis wiring AFTER stove stopped working and expensive inverter wouldnt operate fridge anymore. This inverter would operate TV still." This indicates the inverter was working well enough to support noninductive loads but once you try to run a fridge compressor it fails. To rule this out get a DC amp meter and variable speed power drill to see if it works up to about 8 amps (or a thousand watts), then fails beyond that.

More clarifying questions:

-It's unclear if either the old or new new inverter failed cold. In one case you mention it works for the TV but not the fridge. Did it fail completely and if so is there a fuse (should be) and is it still good?

-It makes no sense that a cheap inverter (100-200 watts as you state) could possibly run a fridge. Did you mis-state (1000 watts with 2000 watts max perhaps)?

-And do you know what the inrush current draw of the fridge is? What kind of fridge?

-Regarding reverse polarity on the inverted, 120vAC lines: I'm wondering if your 'fix' might have introduced a reverse polarity failure elsewhere. Have you traced the conductors, all conductors including any other branch circuits the inverter feeds to check for any other reverse polarity receptacles? A simple plug-in tester can do this.

You have repurposed the lift wire, which may not actually big enough for a fridge inrush current, and the system over time just stressed the inverter. I know that doesn't explain why the second inverter failed so quickly, but I'm not sure you can draw that much from batteries over that wire. Getting a DC amp clamp (Hall Effect) on that wire may help you understand what is actually coming through it.

And finally your batteries are 4 years old and may play into the equation. I get that beep on my inverter if the batteries drop below 12.2 volts, so perhaps you're just not getting the same juice you used to. Thinner wire and fast current draw due to the fridge cycling might have over time stressed the batteries so they failed a little earlier than you hoped. Out of curiosity is your system a 12v or 24v system? And do you have a BMS?

 

[matthews2001]

- did not fail completly, it runs the TV not the fridge.

-The replacement inverter I bought was like $70 at O reilys auto parts. I dont have access to the bus but their website lists a $70 at 500 watts, probably that one.

-fridge is a full size energy star one. Dont remember the current draw but running I think 40 watts? Untill defrost goes on then higher.

I have a 12v system no BMS but have smart charger for batts.

The wire to the lift was hugh, dont know size but...The battery cable run is probably 7 feet for positive, and negative is short run to frame ground which has been diassembled and cleaned very well.


Wondering if reverse electric hookup for 2 years did something though an electrician friend says no. Maybe should mis wire it again!

Thanks all

 

[Rucker]

- did not fail completly, it runs the TV not the fridge.

-The replacement inverter I bought was like $70 at O reilys auto parts. I dont have access to the bus but their website lists a $70 at 500 watts, probably that one.

-fridge is a full size energy star one. Dont remember the current draw but running I think 40 watts? Untill defrost goes on then higher.

I have a 12v system no BMS but have smart charger for batts.

The wire to the lift was hugh, dont know size but...The battery cable run is probably 7 feet for positive, and negative is short run to frame ground which has been diassembled and cleaned very well.


Wondering if reverse electric hookup for 2 years did something though an electrician friend says no. Maybe should mis wire it again!

Thanks all

From everything you said, I recommend you put a volt meter on the system and just monitor voltage. You probably need to replace your batteries.

 

[Ronnie-SKO]

From everything you said, I recommend you put a volt meter on the system and just monitor voltage. You probably need to replace your batteries.

This is what I am thinking as well. Check voltage right at the inverter, and also batteries. If both are the same and drop below 12 the batteries are likely getting weak. Now if the battery voltage does not drop much, but voltage drops at the inverter then the wires are likely to small, or bad connection.



By the way the negative grounding to the frame while ok is not the best for the inverter, it really should have a direct negative to the battery

 

[Rucker]

One more point-it takes a few seconds for the inverter to spin up. If your fridge is plugged in you might want to unplug the fridge and let the inverter capacitors charge up for a few seconds first. Then you can plug in the fridge and see if it isn't just the initial powering up of the inverter that's causing the failure.

 

[kazetsukai]

Your fridge could be the problem. I would plug it into grid power and check for a hot skin condition just in case. My used one did this- it kept tripping GFI in my rig. Removed the GFI for a test, and read 32VAC from the door to the nearest ground point. Yikes.


Aside from this, I would not recommend HF inverters for full house power or surge-y loads like fridges. Would stick to LF inverters.