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Refrigerator Advice [message #311963] Tue, 10 January 2017 12:07 Go to next message
Palmerdad is currently offline  Palmerdad   United States
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I am in the middle of renovating our new to us 1976 Eleganza and need to make a decision about the dead fridge. I have looked into taking it down to Indiana to have it repaired (6 hour drive one way) and am also playing around with getting a new one. If we go the new route our options are wide open and I am curious about getting an energy efficient smaller residential model and running it off of the battery and a pure sine inverter. Our use will be 90% at sites that have electricity and we have the Onan for the rare times we are without. Currently the fridge is the last thing hooked up to propane so a residential fridge would enable me to pull the propane tank and gain extra storage space as well.

The best combination of energy efficiency and space seems to be the GE 5.6 cu. ft. Mini Refrigerator Model GCE06GSHSB. It is obviously smaller than the Norcold we currently have but we just went through a kitchen reno and lived for 3 months with a small fridge about this size with little to no lifestyle changes so I think it will be enough for us on weekends and short trips. It is energy star rated at an annual 236 kWh.

Here is where I need help. I've never been good at math and the whole watts, amps, volts confuses the heck out of me. What would this 236 kWh break down to for a daily draw on a house battery? What gauge wire would I need to run from the 12v system to the inverter to handle this size draw? Also, am I right in thinking the house battery would get enough charge while the vehicle is underway to keep it full even with the fridge running? Any other things you think I'm overlooking in considering this as an option???


-James Palmer, Traverse City, MI 1976 Eleganza
Re: Refrigerator Advice [message #311964 is a reply to message #311963] Tue, 10 January 2017 12:58 Go to previous messageGo to next message
Handyman is currently offline  Handyman   Netherlands
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Hi,

For a AC Compressor Fridge, you need an inverter that can handle the very high, short moment the compressor starts running.
So if the average draw is 65 watts, you need at least an inverter that is capable of 10-15 times that 65 watts !
Even it is for a very short time, once the compressor runs its settles to that 65 watts.
And the inverter has to run constantly, also when the fridge issen't running, so there is a lost of 10-15% extra.

I also switched to a compressor fridge, but choose the 12 volts version from Dometic, the Waeco Coolmatic CRX110.
We don't need a inverter, and now this last weekend, with this low temps, I use 45 Amps / 24 hours.
This is including lights (LED), waterpump, ALDE 3010 heater with warm water reservoir, and 2 hours of television.
Waeco gives an estimate of max 2,5 Amps/hour when the outside temp is 80-90 degrees.

During the ride the batteries are constantly charged by the alternator, and a Votronic Chargebooster 1212-45 Amps max.
When your batteries needs extra charging you could run the generator, but at campsites the combination of charger and batterie will be enough.
Those 12volt compressor fridges are super efficiënt. And in very hot circumstances they are capable of cooling down very good.
But that is also true for domestic fridges. Going for either the domestic AC fridge or the RV/Ships 12volts Fridges, I think is in your situation the best way to go.

People who do a lot of boondocking need to enlarge their batteriebanks and/or additional solar.
During summertime my solarpanels can keepup with the demands of my fridge, lights at night etc ...
Additional, thanks to my chargebooster, I can drive an hour and almost put 45 amps, back in the batteries, when they are discharged for more then 30%.

Daniel

PS: not Based on the situation in a GMC, but a european build Hymer class B+
But that makes for function and making a choise no difference since our 12volts systems are simullar, and the fact that our domestic fridges use 230volt is only a detail Wink


Daniel Jacobs, NL-USA 1977 GMC Eleganza II, Rebuild 455 (2019) 3.55 FD. FiTech and (Modified) FCC, Electric Pump, insulated GasTanks, 100A Alternator, APC, McDash, Schräder Valves + extern Fills, Ceramic Film, TPMS, FlexSteel Seats

[Updated on: Tue, 10 January 2017 13:12]

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Re: Refrigerator Advice [message #311966 is a reply to message #311963] Tue, 10 January 2017 13:06 Go to previous messageGo to next message
A Hamilto is currently offline  A Hamilto   United States
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Palmerdad wrote on Tue, 10 January 2017 12:07
...I've never been good at math and the whole watts, amps, volts confuses the heck out of me. What would this 236 kWh break down to for a daily draw on a house battery? What gauge wire would I need to run from the 12v system to the inverter to handle this size draw? Also, am I right in thinking the house battery would get enough charge while the vehicle is underway to keep it full even with the fridge running? Any other things you think I'm overlooking in considering this as an option???
You can't rely on the numbers from the energy guide. The amount of energy will go up and down the ambient temperature goes up and down. And your particular model will vary from the guide.

But to get you in the ballpark, 236kWh annually is 647 watt-hours per day, or 27 watt-hours per hour. Divide that by 12VDC and you get 2.245 amps effective continuous draw. Multiply that by the 15% loss in an inverter and you get about 2.6 amps effective continuous draw on your house battery bank. It will probably be more like double that half the time (when the fridge is running) and zero the other half of the time.

IF (big capital letters) it doesn't draw more than that, and IF (big capital letters) you could actually get 100 amp-hours out of a battery, and IF (big capital letters) you had nothing else drawing power from your house battery bank, you could go about 38 hours before a 100 amp-hour house battery was dead. Two golf cart batteries might get you to 48 hours or so with other loads on it.

That sub-3 amp load could get by with a 16 gauge wire. I would run 12 gauge.

Yes, the house battery would get enough charge while underway to keep it topped off. Where you will suffer is when there is nothing to charge the house battery. Figure a day maybe with other loads like lights and what-not. Or build a serious house battery bank.

[Updated on: Tue, 10 January 2017 13:08]

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Re: [GMCnet] Refrigerator Advice [message #311967 is a reply to message #311963] Tue, 10 January 2017 13:09 Go to previous messageGo to next message
Gary Worobec is currently offline  Gary Worobec   United States
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This might help you break it down.

Your fridge will most likely draw 3 amps @110 volts. This is 330 watts. (A normal household fridge draws about 7-8 amps @110 volts)

Converting that to 12 volts means that you divide 330/12 equals about 27 amps of 12 volt power.

The duty cycle is a bit tough to figure. How often is the fridge going to run depends on ambient air temp and the amount of ventilation you give it. The more venting the more efficient. In a house there is lots of ventilation. In a GMC not so much.

Lets assume a 30% duty cycle (this is probably on the high side). This means that the fridge will run 8 hours over a 24 hour period meaning that you will use 216 amps through out the day or ABOUT 2000 watts. You will flatten a regular 105 amp battery in about 12 hours.

Wire size for the inverter is dependent on how close it is to the battery source and how big the inverter is. There should be a spec sheet with the inverter to tell you this. From the inverter to the fridge you can use a #12 appliance extension cord.

With a good 120 amp alternator you ought to be able to keep the fridge running while driving but make sure you have at least a #6 or larger wire from the alternator to the batteries. Not sure where your house battery is located but the standard #10 wire will not cut it if that is what you have.. That alternator is going to suck up about 2 horsepower from the engine at full output so make sure the belts are good and you might even consider a double pulley (see JimK for this).

All of the above is making lots of assumptions but it might help you along.


>
> I am in the middle of renovating our new to us 1976 Eleganza and need to make a decision about the dead fridge. I have looked into taking it down to
> Indiana to have it repaired (6 hour drive one way) and am also playing around with getting a new one. If we go the new route our options are wide
> open and I am curious about getting an energy efficient smaller residential model and running it off of the battery and a pure sine inverter. Our use
> will be 90% at sites that have electricity and we have the Onan for the rare times we are without. Currently the fridge is the last thing hooked up
> to propane so a residential fridge would enable me to pull the propane tank and gain extra storage space as well.
>
> The best combination of energy efficiency and space seems to be the
> http://www.homedepot.com/p/GE-5-6-cu-ft-Mini-Refrigerator-in-Black-GCE06GGHBB/205508766. It is obviously smaller than the Norcold we currently have
> but we just went through a kitchen reno and lived for 3 months with a small fridge about this size with little to no lifestyle changes so I think it
> will be enough for us on weekends and short trips. It is energy star rated at an annual 236 kWh.
>
> Here is where I need help. I've never been good at math and the whole watts, amps, volts confuses the heck out of me. What would this 236 kWh break
> down to for a daily draw on a house battery? What gauge wire would I need to run from the 12v system to the inverter to handle this size draw?
> Also, am I right in thinking the house battery would get enough charge while the vehicle is underway to keep it full even with the fridge running?
> Any other things you think I'm overlooking in considering this as an option???
> --
> -James Palmer, Traverse City, MI
> 1976 Eleganza
>
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> Unsubscribe or Change List Options:
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Gary and Joanne Worobec
Anza, CA
1973 Glacier 23




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Re: Refrigerator Advice [message #311970 is a reply to message #311963] Tue, 10 January 2017 13:36 Go to previous messageGo to next message
SteveW is currently offline  SteveW   United States
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Hi Daniel -

"During the ride the batteries are constantly charged by the alternator, and a Votronic Chargebooster 1212-45 Amps max."

I'm very curious about this... I looked at the documentation for this device (in German) and it appears that it takes the alternators current as supplied to the starter battery and provides it to the house battery/batteries as required by them.

How is this different than a traditional combiner ?? (http://www.yandina.com/c100InfoR3.htm)

Thanks and Happy New Year !

Steve W
1973 23'
Southern California




Steve W 1973 : 23' Southern California
Re: Refrigerator Advice [message #311971 is a reply to message #311963] Tue, 10 January 2017 13:45 Go to previous messageGo to next message
lqqkatjon is currently offline  lqqkatjon   United States
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There is no way of telling how much juice the fridge will use. as stated above, the temperature outside and inside the coach varies so much, and the food you have in it, and how often you open the door and how long the door is open.

Both the fridge you posted from home depot, and the fridge Daniel was describing is a lot smaller then the fridge that is standard in your eleganza. I like to have plenty of cold beverages in the coach, and they tend to take up some space.

I just know from my experience, there is cost of trying to boost battery capacity. (solar, bigger battery banks, inverters). and I never could get a long weekend out of my electric only fridge. Before my $700 spending on batteries/solar, I could barely go 24 hours on my stock battery/norcold. Going with a propane fridge, just took all my battery capacity problems away.

I would have no issues getting a decent used fridge. I see no reason to buy $1200 new fridge when you can find a rebuilt or used one for less then $500.

There are other guys out there too other then the guy in indiana, but he is probably the best. We have a re builder in Minneapols/St. Paul, so maybe you do not have to travel that far.








Jon Roche 75 palm beach EBL EFI, manny headers, Micro Level, rebuilt most of coach now. St. Cloud, MN http://lqqkatjon.blogspot.com/
Re: Refrigerator Advice [message #311974 is a reply to message #311970] Tue, 10 January 2017 14:13 Go to previous messageGo to next message
Handyman is currently offline  Handyman   Netherlands
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SteveW wrote on Tue, 10 January 2017 20:36
Hi Daniel -

"During the ride the batteries are constantly charged by the alternator, and a Votronic Chargebooster 1212-45 Amps max."

I'm very curious about this... I looked at the documentation for this device (in German) and it appears that it takes the alternators current as supplied to the starter battery and provides it to the house battery/batteries as required by them.

How is this different than a traditional combiner ?? (http://www.yandina.com/c100InfoR3.htm)

Thanks and Happy New Year !

Steve W
1973 23'
Southern California


Hello Steve,

Here a link in english for the B2B chargebooster, I am talking about.

http://www.votronic.de/index.php/en/products2/series-vcc/standard-version/vcc-1212-45

The big difference to a combiner or diodeblock, is the fact it is a full electronic controlled charger, see it as a charger that has not 110 volts input, but the 12-15 volts the alternator produces, then through sense-lines measures the alternator/startbat current and chargestatus, and the same for the house battery bank. It can be ajusted for different types of batteries, gel, agm, acid-lead, also the manner of input and the speed of charging.

I did also renew my wirering, don't know the diameter for US standards, but I took 16 mm2 diameter high quality cable, 80 amps fuse at startbat side and 50 amps at house battery side. As advised by Votronic.

The big advantige is further more, not only the very good charge charasteristics, but too low input from the alternator side will be brought to a higher level, so the charge voltage is always as needed. Long distance from alternator to house battery will be compensated that way.
And I know that is often an issue in MHs.

They have also an connection for the D+ so the booster only then makes a connection and starts charging when the engine runs.

There are different models availeble, 25 amps, 45 amps and there will be comming soon a 90 amps version.
Also a model especially for LitiumIon batteries.

Even after starting the engine, running at idle (about 800 rpm) the chargebooster charges at 45 amps, and is also tempcontrolled, what is also an advantidge. The batteries are discharged about 30-40%. And it continious very strong.

In the situation before I had the booster installed, it started at 20 amps max, and did go down to 10 .... 8 amps after a short time, since the alternator saw a already fully charged startbatterie ...

Also for all of you a very happy newyear.

Daniel.


Daniel Jacobs, NL-USA 1977 GMC Eleganza II, Rebuild 455 (2019) 3.55 FD. FiTech and (Modified) FCC, Electric Pump, insulated GasTanks, 100A Alternator, APC, McDash, Schräder Valves + extern Fills, Ceramic Film, TPMS, FlexSteel Seats
Re: [GMCnet] Refrigerator Advice [message #311975 is a reply to message #311974] Tue, 10 January 2017 14:22 Go to previous messageGo to next message
Olly Schmidt is currently offline  Olly Schmidt   United States
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Daniel,
> I did also renew my wirering, don't know the diameter for US standards, but I took 16 mm2 diameter high quality cable, 80 amps fuse at startbat side
> and 50 amps at house battery side. As advised by Votronic.

https://en.wikipedia.org/wiki/American_wire_gauge has details.


--
Best regards

Peer Oliver Schmidt
PGP Key ID: 0x83E1C2EA

'76a Eleganza II, VA


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Olly Schmidt
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'76a Eleganza II, VA
'73 Sequoia, SH, Germany
Re: Refrigerator Advice [message #311976 is a reply to message #311966] Tue, 10 January 2017 14:34 Go to previous messageGo to next message
A Hamilto is currently offline  A Hamilto   United States
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Gary Worobec wrote on Tue, 10 January 2017 13:09
This might help you break it down.
Your fridge will most likely draw 3 amps @110 volts. This is 330 watts. (A normal household fridge draws about 7-8 amps @110 volts)...
My power consumption numbers for 12VDC reflect what the energyguide for the fridge would consume. You made me realize that my wire sizing was based on a continuous 2.6A DC and not something like a 10% duty cycle, which would be 10 times that amount. So you need to plug it in and measure the current draw before you can size the inverter and the wire to the inverter.

What is true is that pretty much any guess is going to be off, probably by quite a bit. The only way to know is to put it in the environment in which it will be used and put something like a Kill-A-Watt on it and measure real life. Then insert the inverter into the picture and measure/track the current that traverses the inverter from a full house battery to a dead one. THEN you will have numbers that you can use to figure out how long it will take to run the house battery down.

And any test has to be real life, including opening the door as much as it will be opened and making ice cubes and what-not.

Everyone contemplating a compressor based electric fridge needs to read this: http://www.bdub.net/Refrigeration_in_the_GMC.pdf

Realistically, the only people that can get by without a propane fridge are the people that always plug in, and those with solar panels and charge controller(s). The Onan and a converter/charger is a very inefficient and ineffective house battery charging system.

And if you decide to go solar, battery charging is critical, and rarely gets done right. When you have a day or two to read and reread enough to understand it, read here: https://handybobsolar.wordpress.com/the-rv-battery-charging-puzzle-2/
Re: Refrigerator Advice [message #311977 is a reply to message #311963] Tue, 10 January 2017 14:43 Go to previous messageGo to next message
Handyman is currently offline  Handyman   Netherlands
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.... Smile

Thanks Peer ...

Pffff what a formula ...
And yes I see also the listing.

Lets say I took wires of high quality, almost, as thick as my ringfinger .... Laughing

Since on the startbattery site a max of 65 Amps goes through that wirering, the bigger diameters are better.
There are listing where you can look for what's needed.

Daniel


Daniel Jacobs, NL-USA 1977 GMC Eleganza II, Rebuild 455 (2019) 3.55 FD. FiTech and (Modified) FCC, Electric Pump, insulated GasTanks, 100A Alternator, APC, McDash, Schräder Valves + extern Fills, Ceramic Film, TPMS, FlexSteel Seats
Re: Refrigerator Advice [message #311978 is a reply to message #311963] Tue, 10 January 2017 14:55 Go to previous messageGo to next message
Palmerdad is currently offline  Palmerdad   United States
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Thanks everyone for the info. I understand that in the real world a lot depends on the use. I wonder if the energy star ratings account for some kind of "typical" days use opening the door and what not. IF I were to go this route what would be a good battery configuration. Right now the house has one 12v deep cycle battery which the PO had just installed.

-James Palmer, Traverse City, MI 1976 Eleganza
Re: Refrigerator Advice [message #311979 is a reply to message #311966] Tue, 10 January 2017 15:12 Go to previous messageGo to next message
Palmerdad is currently offline  Palmerdad   United States
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A Hamilto wrote on Tue, 10 January 2017 14:06
Palmerdad wrote on Tue, 10 January 2017 12:07
...I've never been good at math and the whole watts, amps, volts confuses the heck out of me. What would this 236 kWh break down to for a daily draw on a house battery? What gauge wire would I need to run from the 12v system to the inverter to handle this size draw? Also, am I right in thinking the house battery would get enough charge while the vehicle is underway to keep it full even with the fridge running? Any other things you think I'm overlooking in considering this as an option???
You can't rely on the numbers from the energy guide. The amount of energy will go up and down the ambient temperature goes up and down. And your particular model will vary from the guide.

But to get you in the ballpark, 236kWh annually is 647 watt-hours per day, or 27 watt-hours per hour. Divide that by 12VDC and you get 2.245 amps effective continuous draw. Multiply that by the 15% loss in an inverter and you get about 2.6 amps effective continuous draw on your house battery bank. It will probably be more like double that half the time (when the fridge is running) and zero the other half of the time.

IF (big capital letters) it doesn't draw more than that, and IF (big capital letters) you could actually get 100 amp-hours out of a battery, and IF (big capital letters) you had nothing else drawing power from your house battery bank, you could go about 38 hours before a 100 amp-hour house battery was dead. Two golf cart batteries might get you to 48 hours or so with other loads on it.

That sub-3 amp load could get by with a 16 gauge wire. I would run 12 gauge.

Yes, the house battery would get enough charge while underway to keep it topped off. Where you will suffer is when there is nothing to charge the house battery. Figure a day maybe with other loads like lights and what-not. Or build a serious house battery bank.



So, using a hypothetical number of 3 amps per hour to try and account for the losses my 100 aH battery is pretty well drained down 75%-80% after one day. Running my Onan 6k with the new Progressive Dynamics 45 AMP power converter would take roughly 2 hours to bring it back up? (Or am I missing something in the genset charging rate?)


-James Palmer, Traverse City, MI 1976 Eleganza
Re: Refrigerator Advice [message #311980 is a reply to message #311963] Tue, 10 January 2017 15:16 Go to previous messageGo to next message
Handyman is currently offline  Handyman   Netherlands
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Hello James,

Dometic also has a bigger type compressor, the Coolmatic HDC-195, also 12 volts.
Consider also the fact that if you only have to buy a good quality sinus-inverter for you household fridge that operates at 110 volts, those are not cheap.

I see the Coolmatic series operating at 12 volts at prices between 700 and 1400 Euros, and since your dollar is so strong now it will be almost the same in dollars. No extra cabeling for inverter, no extra heavy fuses, no intermittent heavy loads on house batteries.
An average consumption of 3,5 amps//hour, and if the compressor runs at max it is 5-6 amps, so no extra heavy wires necessairy.

If you have already a quality sinus-inverter, with enough power, you can save money buying a domestic fridge.

So you see it still comes down to choosing ... Something you have to do yourself.

Daniel


Daniel Jacobs, NL-USA 1977 GMC Eleganza II, Rebuild 455 (2019) 3.55 FD. FiTech and (Modified) FCC, Electric Pump, insulated GasTanks, 100A Alternator, APC, McDash, Schräder Valves + extern Fills, Ceramic Film, TPMS, FlexSteel Seats
Re: Refrigerator Advice [message #311981 is a reply to message #311963] Tue, 10 January 2017 15:28 Go to previous messageGo to next message
Handyman is currently offline  Handyman   Netherlands
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Quote:
So, using a hypothetical number of 3 amps per hour to try and account for the losses my 100 aH battery is pretty well drained down 75%-80% after one day. Running my Onan 6k with the new Progressive Dynamics 45 AMP power converter would take roughly 2 hours to bring it back up? (Or am I missing something in the genset charging rate?)

Hallo James,

Never drain a lead-accid, gel or agm batterie more then 50%!
So a 100 amps bat gets you only 50 amps at max....
Further a 45 amps charger does not charge continually at 45 amps, it goes down and down since the internal resistance of the battery goes up and up so it will take at least several hours more to top them up ...
But if you go from campsite to campsite, plugging in your rig, bringing up your batterie capacity could do the trick in getting enough "juice" for the fridge while shopping and taking a rest, during the day. Go from 100 to 200 or some more ... And you could even boondock or stay at a Walmart for a night.
With my Coolmatic, and not charging at all, I use with light, heating, waterpump and some tv, 45 amp/24 hours, so if you stop after a days ride at 4 pm, and drive next day at 8 am you have a period of 16 hours were your battery has to do its job, count perhaps 3 amps/hour and even the 100 amps battery should do the job, but comes to quick to its limit, so upgrading to 200 or some more, and you could even stay sometime longer. In summer it will be perhaps 10-20 amps more. It all comes down to making your calculations.

Those 12 volt fridges are very A++ ... Wink
Also as long as the engine runs, so the alternator runs and keeps the batteries at the max, also gives enough for the fridge.

Daniel


Daniel Jacobs, NL-USA 1977 GMC Eleganza II, Rebuild 455 (2019) 3.55 FD. FiTech and (Modified) FCC, Electric Pump, insulated GasTanks, 100A Alternator, APC, McDash, Schräder Valves + extern Fills, Ceramic Film, TPMS, FlexSteel Seats

[Updated on: Tue, 10 January 2017 15:39]

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Re: Refrigerator Advice [message #311982 is a reply to message #311979] Tue, 10 January 2017 15:33 Go to previous messageGo to next message
lqqkatjon is currently offline  lqqkatjon   United States
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Others may chime in on the actual math, but the batteries charge rate will vary. I think it takes longer then 2 hours to charge up a house bank drained down 75%. the batteries will not take the full 45 amps.

i can only say my experience. with my original 12v marine battery, the fridge seemed to kill the battery in a 24 hour period or less. I then upgraded to 2ea 6v golf cart batteries, about 215 amp hour, and it would last 36-48 hours. I added 65 watt solar, and it did not really add any time, batteries were drained dead by sunday morning when I had rolled into camp friday night. I then stated putting Ice in the fridge, and it seemed to help getting me through Sunday.

with my 2 golf cart batteies drained all the way down, a 2 hour drive home(alternator charge), they were charged up quite a bit, but never topped off 100%.

remember when the sun hits the coach, and you are not running A/C, it can get really hot. Also the back of the coach fridge is usually exposed to outside temps. (obviously not the case if you install a residential unit, you will probably close off the back of the fridge compartment).

there are people who run electric fridges and are plenty happy with them. My experience though, is if you ever want to make it longer then 2-3 days without a power cord, then a propane fridge is the way to go.




Jon Roche 75 palm beach EBL EFI, manny headers, Micro Level, rebuilt most of coach now. St. Cloud, MN http://lqqkatjon.blogspot.com/
Re: Refrigerator Advice [message #311984 is a reply to message #311963] Tue, 10 January 2017 15:53 Go to previous messageGo to next message
Palmerdad is currently offline  Palmerdad   United States
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From everything I'm hearing and from Rob Allen's article I'm thinking all electric might work for us. For instance, we are planning a road trip this Summer for 2 weeks. (This will be the longest use I can see us doing at this point in our lives, the rest will be weekends to state parks with hook ups) During that 2 weeks most camping will be at places with hook ups. We might have a night or 2 at a Walmart on our way but that will be after an 8 hour drive and before another 8 hour drive so the battery charge shouldn't be a problem. When we camp at Yellowstone I want to stay at Canyon campground which does NOT have hook ups. The 4 days there will be a challenge. We don't have a toad so we will be driving the GMC around each day so that will help a bit. I will just have to find time to run the genset 2-3 hours a day to keep everything going. All the lights we have are being converted to LED and we will use the bathrooms for showers/hot water use. We do have a small TV I let the kids watch while we're on the road but we don't like it to be on when we arrive as the whole point is to get out and enjoy nature and being together. The GE model I'm looking at claims a 27 watt an hour rate so even with the 85% inverter inefficiency we will be around Rob Allen's 30 watt goal. It sounds like what I would really need to do is get a couple of golf cart batteries to replace the one battery I have now.

So I understand I won't be saving money after I buy new batteries and a pure sine wave charger (in addition to the fridge). What I will gain is the ability to better close up and insulate the part of the coach where the fridge is as well as give myself a new storage compartment where the propane tank sits. Both would be nice. I'll probably keep analyzing this for days to come!


-James Palmer, Traverse City, MI 1976 Eleganza
Re: Refrigerator Advice [message #311985 is a reply to message #311963] Tue, 10 January 2017 16:01 Go to previous messageGo to next message
TR 1 is currently offline  TR 1   United States
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FWIW, we've had the Avanti 7.4 residential fridge for about a year now. We have a largish inverter (Xantrex 2500) and the combination has been great. According to the display on the xantrex, we will see 7-800 watts at startup for maybe a second or 2, then it settles down to around 50 watts running. We have 2 pairs of Trojan 125s, and running on only one pair we get about 2 days out of the batteries before the Xantrex automatically shuts them off when it senses them discharged. I can then either flip over to the other set of batteries, or we need to plug in, run the gen or coach engine, etc. This is running a minimum amt of other stuff off the batts in that time.

The price on the amazon link below can be beat if you shop around... I think we paid $250-300 delivered. We already had an inverter, but to me it makes more sense to buy a residential fridge and use the savings over a 3 way to buy an inverter (which is useful in itself), unless you do a large amt of boondocking.

https://www.amazon.com/Avanti-RA7316PST-Apartment-Refrigerator-Platinum/dp/B00D1SZNO6


Mark S. '73 Painted Desert, Manny 1 Ton Front End, Howell Injection, Leigh Harrison 4bag and Rear Brakes, Fort Worth, TX
Re: Refrigerator Advice [message #311986 is a reply to message #311985] Tue, 10 January 2017 16:08 Go to previous messageGo to next message
TR 1 is currently offline  TR 1   United States
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TR 1 wrote on Tue, 10 January 2017 16:01
FWIW, we've had the Avanti 7.4 residential fridge for about a year now. We have a largish inverter (Xantrex 2500) and the combination has been great. According to the display on the xantrex, we will see 7-800 watts at startup for maybe a second or 2, then it settles down to around 50 watts running. We have 2 pairs of Trojan 125s, and running on only one pair we get about 2 days out of the batteries before the Xantrex automatically shuts them off when it senses them discharged. I can then either flip over to the other set of batteries, or we need to plug in, run the gen or coach engine, etc. This is running a minimum amt of other stuff off the batts in that time.

The price on the amazon link below can be beat if you shop around... I think we paid $250-300 delivered. We already had an inverter, but to me it makes more sense to buy a residential fridge and use the savings over a 3 way to buy an inverter (which is useful in itself), unless you do a large amt of boondocking.

https://www.amazon.com/Avanti-RA7316PST-Apartment-Refrigerator-Platinum/dp/B00D1SZNO6


Just to add, please remember the 50 watts is "running"... The fridge only runs maybe half the time. Our inverter I believe is a modified sine wave, which are much cheaper than the true sign. Have not noticed any issues running the modified sine inverter for our uses.


Mark S. '73 Painted Desert, Manny 1 Ton Front End, Howell Injection, Leigh Harrison 4bag and Rear Brakes, Fort Worth, TX
Re: Refrigerator Advice [message #311989 is a reply to message #311963] Tue, 10 January 2017 16:19 Go to previous messageGo to next message
tgeiger is currently offline  tgeiger   United States
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I see there was a lot of good information pertaining to the electrical setup. I did not see anyone discuss the propane setup. I don't know if that is because it just does not perform well or if the original preference was leaning to electric? I too have been debating this issue and would like to boondock at times so I was leaning towards a 3-way fridge for most flexibility. Any thoughts pertaining to that?

Thanks,
Tom
76 Eleganza II with electrical fridge now


Tom Geiger 76 Eleganza II KCMO
Re: Refrigerator Advice [message #311993 is a reply to message #311979] Tue, 10 January 2017 17:17 Go to previous messageGo to previous message
A Hamilto is currently offline  A Hamilto   United States
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Palmerdad wrote on Tue, 10 January 2017 15:12
So, using a hypothetical number of 3 amps per hour to try and account for the losses my 100 aH battery is pretty well drained down 75%-80% after one day. Running my Onan 6k with the new Progressive Dynamics 45 AMP power converter would take roughly 2 hours to bring it back up? (Or am I missing something in the genset charging rate?)
The PD won't charge the batteries completely in only 2 hours. The voltage isn't high enough for long enough to do the job. You will get it back to 60% maybe, then drain even farther the next day, run the genset long enough to get it back to 55%, and so on until the battery is toast.

It takes a lot of digesting because the author is long-winded and buries the gold pretty deep in his writing, but the second link I provided says that a battery needs to be brought to WELL OVER 14 volts AND HELD THERE for a lot longer than any commercially available converter/charger will do. An RV converter/charger will run at 13.6 volts or so for a bit then drop off to 13.2 long before the battery is charged. Some SOLAR CHARGE CONTROLLERS can be reprogrammed from factory default to do the job. But an RV converter/charger ain't gonna do it. A converter/charger would need to run a couple of days to completely charge a battery.
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