Powering refrigerator.

[lappir]

I have come across 4 6 volt deep cycle batteries at a good price. The first two that I have seen have Interstate Golf written on them. I dropped them off at a local battery store (not interstate) for testing and charging. I had hoped they would have an inverter charger they could couple with the batteries and I could take everything home and use the setup to power my refrigerator. They were able to only do the testing and charging. Their abilities to obtain inverters has been hampered. 

Renology is the first one to come up this morning on an internet search. I know I have read about some of their systems on the forum. 

Any other brands I need to look at? I want to get 12 to 24 hours of power for the fridge during moving days. 

Rod

[Bill Joyce]

I like https://www.donrowe.com/Default.asp for buying inverters and you can call them for advice,

[hemsteadc]

It's Renogy, not Renology.  Look at Outback and Magnum.

Edited December 24, 2021 by hemsteadc

[oldjohnt]

I just can't remember all the brands of Inverters I've owned over many years, best I recall the last few were Xantrex, one from Camping World and Renogy 2KW PSW. Unfortunately, both the Xantrex and Camping World (Green something ??) failed prematurely while the Renogy is still going strong works perfect, but that's just one persons experience and I'm sure others had different. Magna and Victron are quality units. For sure I recommend a PSW hard wired unit (NOT any small plug in type), located close to the batteries with big enough cables to minimize line voltage drop, and high enough rated to allow for the higher than normal initial start up current which depends on the fridge you plan to operate. If you happen to need BOTH a Charger/Converter PLUS an Inverter, I would go with a combination Inverter/Charger with a Smart Multi Stage charger compatible with your chosen battery chemistry.

 The last time I used four 6 volt Deep Cycle FLA Golf Cart batteries in series/parallel, such had a rating of 450 Amp Hours of which 50% or 225 was useable, so IF you know how many Amp Hours the fridge requires over X time you can do the math. Of course you need a method to recharge, be it shore power or genset or utility but thats another story

PS  I have seen some residential 120 VAC Compressor fridges ran using a 1KW Inverter but to allow for other use and future expansion Id opt for a 2 KW even if 1 would work SUBJECT TO FRIDGE REQUIREMENTS maybe more maybe less. 

PS I would take a serious look at the 12 VDC powered fridges if you were starting a new to save on Inverter inefficiency

 Run an energy audit,,,,,,,,,, have the batteries LOAD TESTED (good way to determine their condition),,,,,,select a big enough Inverter or Inverter/Charger  YOUR MONEY YOUR CHOICE

 

 John T

 

Edited December 24, 2021 by oldjohnt

[lappir]

Thank you for the replies. This morning probably wasn't a good day to look, but I just got the batteries a couple days ago. 

The fridge has been in my home since new in 2013 It's a residential model with the bottom freezer. According to the builder (of the home) my inverter and two batteries should have worked. It did not. Maybe because it's a modified sine or maybe something else. I only want to power the fridge for at least 12 and hopefully 24 hours. I'll find a location that will help me with finding out how much current is required. It may be in the "Book" provided with the unit. 

In the future I will cover the top of my home with solar and have a large enough battery bank to survive for a few days of darkness. My power usage is minimal. The current park provides 800 KW or something or other each month. If I go over I have to pay for the amount over. Last month it was less than 600. If it stays mild here I doubt it will go up much over that. I use my Mini Split, the fridge, computer, TV, coffee maker and occasionally the microwave or induction hot plate. The electric portion of the water heater is currently not being used. I just retired the "Bunn" coffee maker not sure how much current it used to keep the reservoir  of water hot. 

Until then thanks again, 

Rod

[Chad Heiser]

If you want a dedicated inverter just for the refrigerator, it will either need to have a built in transfer switch (so it can pass shore power through or power the refrigerator from battery) or you will need a small external transfer switch.  Most small inverters used to power a refrigerator (1000 watts or less) are unlikely to have built in transfer switches. 

If you are interested, I have the 1000 watt pure sign wave Magnum 1012 inverter (I know you don't do Amazon, but this is just for information on what it is).  I just took out of my trailer when I redid my system and it is available (much cheaper than new).  It is a high quality inverter and simple to hook up and use.  I also have the remote on/off switch for it (and in line Class T fuses and fuse holder for circuit protection).  When you couple it with a Magnum CSW-TS15, it will run the refrigerator from either shore power or battery automatically.  I have two of these transfer switches in my trailer (I left them in with the new install so they are not available from me).  One is on the refrigerator circuit and the other is on a circuit in my bedroom to keep my bedside clock going.  I tied both of them into the 1012 inverter with simple 12 gauge extension cords.

[dons118]

Are you just wanting to power the refer for a move of 12-24 hours? If so, you do not need to power it at all.

Due to a transfer switch problem, I went over 72 hours without power to the refer. Everything was still frozen and the refer section was still in safe temperature range. Even if a refer is plugged in, the compressor only runs about 10 minutes per hour.

If you have to open the door, think about what you want before and don't just open the door and "surf" the contents

Edited December 24, 2021 by dons118

[lappir]

37 minutes ago, Chad Heiser said:

If you want a dedicated inverter just for the refrigerator, it will either need to have a built in transfer switch (so it can pass shore power through or power the refrigerator from battery) or you will need a small external transfer switch.  Most small inverters used to power a refrigerator (1000 watts or less) are unlikely to have built in transfer switches. 

If you are interested, I have the 1000 watt pure sign wave Magnum 1012 inverter (I know you don't do Amazon, but this is just for information on what it is).  I just took out of my trailer when I redid my system and it is available (much cheaper than new).  It is a high quality inverter and simple to hook up and use.  I also have the remote on/off switch for it (and in line Class T fuses and fuse holder for circuit protection).  When you couple it with a Magnum CSW-TS15, it will run the refrigerator from either shore power or battery automatically.  I have two of these transfer switches in my trailer (I left them in with the new install so they are not available from me).  One is on the refrigerator circuit and the other is on a circuit in my bedroom to keep my bedside clock going.  I tied both of them into the 1012 inverter with simple 12 gauge extension cords.

Thanks Chad, I will think about it. Does that inverter have a charger or will I have to figure another way to keep my batteries charged? My thought was to just power the fridge through the inverter all the time and then I wouldn't have to worry about the transfer switch. I know it's not "Efficient" to do that, but will it do any harm? Won't have to worry if the power goes out for a bit. 

dons118, I have gone 12 to 24 hours without having the fridge running and all is good most of the time. One of my locks failed on the fridge door once and who knows how often it opened and closed without me knowing about it. I found the door closed, but the glue had come off of one of the securement devices and it was on the floor so I know the door opened at least once. Everything was thrown away after that trip that was inside. Maybe if the fridge had been running when the door closed it would have caught back up????

I didn't get the batteries picked up after they were tested and fully charged before the shop closed for the weekend. Will get them Monday. 

Thanks again for the replies and suggestions. 

 

Rod

[Chad Heiser]

1 hour ago, lappir said:

Thanks Chad, I will think about it. Does that inverter have a charger or will I have to figure another way to keep my batteries charged? My thought was to just power the fridge through the inverter all the time and then I wouldn't have to worry about the transfer switch. I know it's not "Efficient" to do that, but will it do any harm? Won't have to worry if the power goes out for a bit. 

This inverter is an inverter only, it doesn't have a charger.  It will be hard to find an inverter/charger in the size (small) you would use to dedicate just to a refrigerator.  Adding a basic battery charger would be simply and it could plug into an existing outlet in your rig.  

Based on your question, I am assuming you want to dedicate a battery bank and inverter to the fridge only, nothing else.  It isn't the most efficient way to set the system up, but it is possible.

[Jack Mayer]

I'm a little confused as to what you want to do. Do you want a general use inverter that is not used often, but is available for things (like) your microwave? Or do you truly want a dedicated inverter to the fridge? In either case you will have to have a means to charge the battery bank, so you need an inverter charger - or a separate charger. 

On trucks - that have essentially the same needs - we use a Kisae Abso 2000 watt pure inverter/charger with a transfer switch. It has direct wire capability, and a display panel that is able to be mounted remotely. It is well priced and pretty good quality. I've been using these for many years as the "reduced cost" inverter. It is not as good as a Victron, Outback, Magnum, etc but the reduced price makes it attractive, as does the feature set. They are well built and I doubt there are any more issues with them than any other line. I've probably installed 50+ of these over the years with no issues. Here is the one we use.  LINK

Edited December 25, 2021 by Jack Mayer

[oldjohnt]

19 hours ago, lappir said:

The fridge has been in my home since new in 2013 It's a residential model with the bottom freezer. According to the builder (of the home) my inverter and two batteries should have worked. It did not. Maybe because it's a modified sine or maybe something else.

Older fridges may not be as efficient as the later models and what someone THINKS will suffice may or may not be correct !!!!!!!!! I highly recommend a Pure Sine Wave regardless and the size again DEPENDS ON THE FRIDGE LOAD including initial inrush higher start up current. Of course if you need a whole house versus the fridge only determines what size of an Inverter you need but for a residential fridge ONLY about 1KW is the smallest Ive seen used, but again a 2KW allows for future expansion ALTHOUGH for a whole house you may be looking at a 3KW minimum where brands such as Victron shine. With only 400 AH of FLA battery capacity and 200 useable you may or may not be able to run a fridge 24 hrs SUBJECT TO WHAT THE FRIDGE REQUIRES that's also further subject to ambient temps, efficiency and how long and often the door is open ?????? Whole house versus fridge only also determines your transfer switching method.

 Find out the energy the fridge may need over 24 typical hours,,,,,,,determine how may actual amp hours of stored energy your batteries can supply if full charged,,,,,,,decide on fridge only or other inverter use,,,,,,,,,,,,,then you can size the Inverter and calculate how long your batteries will last before recharging YOU GOTTA RUN AN ENERGY AUDIT AND DO THE MATH   to arrive at a more accurate answer. Regardless my best guess (fridge only maybe a bit more) is I would use at least a 2KW PSW the brand and price is YOUR choice.........

 Best wishes, post back any other questions

 John T  

[lappir]

Sorry for the confusion. 

I don't want to have to worry about the fridge. Don't really care about much else at this time. 

I wouldn't be doing anything, but got what I think is a good deal on 4 6 volt deep cycles.

 

I have been waiting to replace my OEM batteries until they wouldn't allow the 12 volt lights to work when I unplug. That may take a while and the replacement batteries came up recently, so I started thinking about how to get the fridge to do what I want with an inverter all it's own. 

I could replace the MSW 3K inverter with a high quality PSW and use the 4 batteries together and maybe have more choices of what I want to power. The likelihood of plugging in a bunch of portable heaters isn't as high as it was during the first days of ownership of this home. 

 

An energy audit is a great idea and one day a professional will preform one and help me with a total solar/battery system so I won't ever have to plug in again. 

Rod 

[oldjohnt]

1 hour ago, lappir said:

I could replace the MSW 3K inverter with a high quality PSW and use the 4 batteries together and maybe have more choices of what I want to power. The likelihood of plugging in a bunch of portable heaters isn't as high as it was during the first days of ownership of this home. 

 

An energy audit is a great idea and one day a professional will preform one and help me with a total solar/battery system so I won't ever have to plug in again. 

Thanks for the update Rod, For sure a good quality adequate sized PSW Inverter and four GOOD?? batteries can run a residential fridge for X hours. Even if a cheaper MSW works on some appliances I still recommend a PSW. True an energy audit is the way to better design an entire system. I hesitate to recommend brands other than the personal experience I posted above. One person on here can testify a certain brand worked great for him while another says they are terrible lol. I enjoy watching DIY Solar by Will Prowse and his reviews.

 There's plenty of Inverter brands as well as reviews and opinions out there so do your homework and make YOUR choice

 John T

[Lou Schneider]

When I installed a residential refrigerator in my Arctic Fox trailer, the thing that limited how long I could run it on battery power was the compressor's starting surge.  As lead acid batteries discharge both their voltage and available current delcine and the starting surge pulled the battery voltage down enough to trip the low voltage cutout in the inverter.

If I was doing this again, I'd install a Super Capacitor right at the inverter to handle the starting surge.  People have used Super Capacitors to start car engines, though one of this size may be overkill.  Or upgrade to lithium batteries which don't fade out the way lead acid batteries do.

[hemsteadc]

On 12/25/2021 at 9:04 AM, lappir said:

I have been waiting to replace my OEM batteries until they wouldn't allow the 12 volt lights to work when I unplug.

That's not a great idea.

[KodiakJack]

I use remote outlets to shed load from the inverter and batteries, including our residential refrigerator, that will stay cold for long periods.

Later,

J