Nova Kool R3800 AC/DC Refrigerator

[booster]

Originally Posted by Roadtrek Adventuous RS1

OK...on another thread.... someone has suggested that my two 224 Ah deep cycle AGM 6 volt batteries may not be enough reserve capacity to run a compressor refrigerator that has a maximum 2.2 amps per hour draw......

I also have a 160 Watt Zamp Solar Panel system producing 9 amps per hour...

I don't expect that the refrigerator will even run 24/7.... but, even if it did that would be a total of 52.8 amps per day in 24 hours.....

What do you think???

What am I missing here???

If you are referring to the one I just started, nobody said that at all. That thread is about what information is needed to make an informed choice about compressor frig brands



Why are you repeating the same question again and again trying to get somebody to agree with what you already have decided? If you had half that much battery, it would likely be not enough, and if you had double that much, it would very likely just fine. In between you have to do an analysis to get an idea and not just guess. Do the work.



Many folks on the here said that it may or may not be enough based on lots of other conditions, and that is the way it is.


Take or leave it, but accept what people who have done it are telling you on frig, solar, and battery capacity.

[hbn7hj]

Originally Posted by Roadtrek Adventuous RS1

I don't expect that the refrigerator will even run 24/7.... but, even if it did that would be a total of 52.8 amps per day in 24 hours.....

What do you think???

What am I missing here???

Well, for one, a correct sentence.

"be a total of 52.8 amp-hours per day" would be correct.

Bottom line is most of us don't think you have enough battery or solar.

[Roadtrek Adventuous RS1]

Originally Posted by hbn7hj

Well, for one, a correct sentence.

"be a total of 52.8 amp-hours per day" would be correct.

Bottom line is most of us don't think you have enough battery or solar.

So.... you really believe that the refrigerator will draw all of the 52.8 amps per day in 24 hours?

What about my 30 or 40 amps recovery by the solar?

Explain that to me... don't just say it's not enough power... that's not a good explanation...

[booster]

Originally Posted by Roadtrek Adventuous RS1

So.... you really believe that the refrigerator will draw all of the 52.8 amps per day in 24 hours?

What about my 30 or 40 amps recovery by the solar?

Explain that to me... don't just say it's not enough power... that's not a good explanation...

Nobody will be able to explain that to you because nobody has enough information to know for sure, as you have been told over and over.

You don't know the actual SOC of your batteries when you stop for the day (worst case and typical)

You don't know your daily use

You don't know how much the frig will use in you insttall in your use pattern, except for based on others information, and a guess at what conditions you will be in. The install could easily double the energy the frig uses.

You don't know how much you will get from your solar on any give day.

You haven't said what the max amount of time your are needing to sit without running the van or generator, or the typical time.


You haven't said how long your driving time are min, max, typical.


All anyone can do is guess at this point, based on personal experience, and that is what hbn7hj has done. I will not even venture a guess as I have no idea how accurate even the little bit of information we have is.

[Roadtrek Adventuous RS1]

Originally Posted by booster

Nobody will be able to explain that to you because nobody has enough information to know for sure, as you have been told over and over.

You don't know the actual SOC of your batteries when you stop for the day (worst case and typical)

You don't know your daily use

You don't know how much the frig will use in you insttall in your use pattern, except for based on others information, and a guess at what conditions you will be in. The install could easily double the energy the frig uses.

You don't know how much you will get from your solar on any give day.

You haven't said what the max amount of time your are needing to sit without running the van or generator, or the typical time.


You haven't said how long your driving time are min, max, typical.


All anyone can do is guess at this point, based on personal experience, and that is what hbn7hj has done. I will not even venture a guess as I have no idea how accurate even the little bit of information we have is.

Booster, I appreciate your time and consideration...so, let me provide you with the worst case ....

According to Nova Kool...if you believe them.... I don't know why anyone would question it.... their R3800 ...12 volt refrigerator using a Danfross compressor... uses a maximum of 2.2 amps per hour... they said that in a 24 hour day... that's 2.2 times 24 or 52.8 amps......

Assuming I have a full charge on my two AGM batteries rated for 224 amps.... and could rely on 112 amps of power ... that's 50 percent.... not even counting my solar panels....

When you add the anticipated ,40 amps of solar... for the day.....it gets better.....

According to Nova Kool... their refrigerator will not even run 24 hours...it cycles on and off....

Perhaps some people, not you, thought that I would have to run my inverter to make this work.... since it's on a 12 volt system... I don't think., maybe I'm wrong.. that I don't have to even switch on the inverter....

Again, I'm thinking worst case....24/7... I don't think it would be this much unless it's 100 degrees outside or hotter...

I would anticipate cooling down the system on shore power before I add any food and the system would only have to maintain the temperature....

I would expect that the refrigerator would run fine overnight for 10 hours without solar.. just on the batteries.

Plus, whenever I'm driving...the system would be charging...is that correct?

----Mark

[Davydd]

If you are in about 80F temperatures and above you will have a compressor refrigerator running all the time because it cannot keep up with cooling. Manufacturers only publish the optimum conditions.

[Roadtrek Adventuous RS1]

Originally Posted by Davydd

If you are in about 80F temperatures and above you will have a compressor refrigerator running all the time because it cannot keep up with cooling. Manufacturers only publish the optimum conditions.

David,. even if it does run 24 hours... that's 52 amps per day ...I'm probably going to reclaim at least 30 amps on the solar panels and have the 224 amps system....

Overnight... it would not be 80 degrees...

I know that I can rely on 112 amps of power ... that would be 50 percent of the battery bank.....

Other people think that this is too low on power...do you?

[BillsPaseo]

Originally Posted by Roadtrek Adventuous RS1

Booster, I appreciate your time and consideration...so, let me provide you with the worst case ....

According to Nova Kool...if you believe them.... I don't know why anyone would question it.... their R3800 ...12 volt refrigerator using a Danfross compressor... uses a maximum of 2.2 amps per hour... they said that in a 24 hour day... that's 2.2 times 24 or 52.8 amps......

Assuming I have a full charge on my two AGM batteries rated for 224 amps.... and could rely on 112 amps of power ... that's 50 percent.... not even counting my solar panels....

When you add the anticipated ,40 amps of solar... for the day.....it gets better.....

According to Nova Kool... their refrigerator will not even run 24 hours...it cycles on and off....

Perhaps some people, not you, thought that I would have to run my inverter to make this work.... since it's on a 12 volt system... I don't think., maybe I'm wrong.. that I don't have to even switch on the inverter....

Again, I'm thinking worst case....24/7... I don't think it would be this much unless it's 100 degrees outside or hotter...

I would anticipate cooling down the system on shore power before I add any food and the system would only have to maintain the temperature....

I would expect that the refrigerator would run fine overnight for 10 hours without solar.. just on the batteries.

Plus, whenever I'm driving...the system would be charging...is that correct?

----Mark

You mentioned that you have two 6V 112AH batteries in series. When mounted in series, you can't add the AH of the two batteries. Two 12V in parallel allows you to add the capacity, but in series, the capacity is equal to the average of the two battery capacities. So you actually have 112AH capacity at 12V. Assuming 50% usable capacity, you have 56AH available capacity. That is not very much. You would be much better off with two 12V 105AH or larger AGMs in parallel.

Good explanation of this here: https://www.schneider-electric.us/en/faqs/FA229757/

And as I mentioned earlier, I have 200W of solar, and I rarely see 9A coming out of my panel when I check on my Zamp monitor. 5A to 6A is much more common, and on a cloudy day, maybe 2A. You are only going to get anywhere close to that peak 9A at high noon on a cloudless day.


Edit: I misread your earlier post. I see you do have two 224AH batteries, so you do have 112AH usable capacity.

[booster]

A weird thing we found in talking to people in campgrounds is that they define an offgrid "day" differently.


It can be a simple overnight to some.


24 hours to some


It can be arrive in the evening, overnight, spend a full daylight, another overnight and out in the morning to others.


Basically, it covers from about 10 hours to more like 36 hours.


Needless to say they use different amounts of power.

[RossWilliams]

If you are in about 80F temperatures and above you will have a compressor refrigerator running all the time because it cannot keep up with cooling.

We have a Norcold compressor refrigerator that we leave on all the time including humid 80F+ weather. It doesn't run continuously and it keeps ice cream frozen solid even set above its lowest setting. Our usage may not be typical, we tend to keep it full and don't go in and out of it much.

Our 240 watt solar panel provides more than enough power to keep it running.

I see you do have two 224AH batteries, so you do have 112AH usable capacity.

That 224AH is assuming you are drawing it down for 20 hours which means a rate of over 11 amps per hour. The AH if you are drawing it down at 3 amps per hour is going to be much higher than that depending on the Peukert constant of the batteries. Its likely to last almost 48 hours at that low draw before it hits 50% discharge. If you are talking about compensating for occasional cloudy weather, you can draw it down to 20% before you need to shut it off. That's going to give you over 3 days if you are parked out of the sun.

[GeorgeRa]

Originally Posted by RossWilliams

The AH if you are drawing it down at 3 amps per hour is going to be much higher than that depending on the Peukert constant of the batteries…………………...

Introducing Peukert constant shows your knowledge of this subject in depth, I need to think. Just those nasty amps per hour I need to digest.

[Roadtrek Adventuous RS1]

Originally Posted by RossWilliams

We have a Norcold compressor refrigerator that we leave on all the time including humid 80F+ weather. It doesn't run continuously and it keeps ice cream frozen solid even set above its lowest setting. Our usage may not be typical, we tend to keep it full and don't go in and out of it much.

Our 240 watt solar panel provides more than enough power to keep it running.



That 224AH is assuming you are drawing it down for 20 hours which means a rate of over 11 amps per hour. The AH if you are drawing it down at 3 amps per hour is going to be much higher than that depending on the Peukert constant of the batteries. Its likely to last almost 48 hours at that low draw before it hits 50% discharge. If you are talking about compensating for occasional cloudy weather, you can draw it down to 20% before you need to shut it off. That's going to give you over 3 days if you are parked out of the sun.

Ross, thanks.

I only need about 10 or 12 hours parked out of the sun....

As I mentioned before .... I try to avoid camping in the rain, stormy weather, and don't usually stay too long at any place. Even if I were stopping for a few days...I normally drive my rig to the local market or run the generator.

[SteveJ]

Without doing an amp hour budget of all the electrical demands or knowing how long the OP wants to boondock this whole thread is pretty much an exercise in futility.

I will say, though, concerning Boosters comment on overnight boondocking length, you'll probably be fine for that, maybe. It all depends...like I said, an exercise in futility.

[Roadtrek Adventuous RS1]

Originally Posted by SteveJ

Without doing an amp hour budget of all the electrical demands or knowing how long the OP wants to boondock this whole thread is pretty much an exercise in futility.

I will say, though, concerning Boosters comment on overnight boondocking length, you'll probably be fine for that, maybe. It all depends...like I said, an exercise in futility.

Steve, as you know.... solar panels are constantly working whenever the sun is shinning.....

All I have to be concerned about is at night. ..the next morning the panels should charge up my system.

Yes, we do use a few lights at night and the bathroom ...

[RossWilliams]

"Yes, we do use a few lights at night and the bathroom ... "

The pump for water to flush the toilet is a non-issue. I think part of the problem here is that people have a hard time getting their head around a refrigerator that takes less power than a 60 watt light bulb. Assuming you are using LED lights, they are basically irrelevant.

If you have to turn on the inverter to watch TV, then you may have a problem. Those two together can use 250 watts which translates to about 20 amps at 12 volts. So you probably can't spend your entire evening in front of the tube and expect to boondock very long. Or vice versa, if you are boondocking you can't spend your evening in front of the TV.

That said, I think you should remember a solar panel's production can vary a lot day to day. You need to be able to survive its worst days. So if you run the batteries down one night and its heavy fog the next day you need to be able to run off batteries through that day and the next night without any production from your panel. Or you need a feasible alternative source of power to charge them.

[Roadtrek Adventuous RS1]

Originally Posted by RossWilliams

"Yes, we do use a few lights at night and the bathroom ... "

The pump for water to flush the toilet is a non-issue. I think part of the problem here is that people have a hard time getting their head around a refrigerator that takes less power than a 60 watt light bulb. Assuming you are using LED lights, they are basically irrelevant.

If you have to turn on the inverter to watch TV, then you may have a problem. Those two together can use 250 watts which translates to about 20 amps at 12 volts. So you probably can't spend your entire evening in front of the tube and expect to boondock very long. Or vice versa, if you are boondocking you can't spend your evening in front of the TV.

That said, I think you should remember a solar panel's production can vary a lot day to day. You need to be able to survive its worst days. So if you run the batteries down one night and its heavy fog the next day you need to be able to run off batteries through that day and the next night without any production from your panel. Or you need a feasible alternative source of power to charge them.

We have some florescent lights and some LED lights...
We do have an inverter and I know that's a big power draw.... probably so is the hot water heater?

Our other power draw is the fan that runs the propane heater.....if it's cold...

We also have an electric motor that folds the bed up and down... usually use this twice a day... putting it down at night and up in the morning.....

As for foggy days..... we have a generator ...if we need to run something or just start the vehicle.. I found that running the engine is pretty quiet and charges up the batteries pretty fast.

Interesting about the bathroom ... I don't know if some people have a pump flush? Our unit has an electric motor for this.... just like turning on the water ....

[mikeehlert]

Have the Nova Kool RFU 6200 in our 2017 Paseo with standard dual AGMs like a prior poster. System Keeps up okay for 36 hours (2 nights) including CPAP, and exhaust fan. Then it needs generator or drive time to get enough for another night in the summer.

[RossWilliams]

probably so is the hot water heater?

If you are using electricity to heat water, then yes it is likely a very large draw. But I assume you are heating with propane so I am not sure the water heater requires any significant power. But this is why its really impossible for someone else to say what you need. It depends on your rig, your use and how you define "need".

mikeehlert "Then it needs generator or drive time to get enough for another night in the summer."

Do you have a solar panel?

[Roadtrek Adventuous RS1]

Originally Posted by RossWilliams

If you are using electricity to heat water, then yes it is likely a very large draw. But I assume you are heating with propane so I am not sure the water heater requires any significant power. But this is why its really impossible for someone else to say what you need. It depends on your rig, your use and how you define "need".



Do you have a solar panel?

Yes and yes. I have a solar panel system on the roof and it's a propane water heater... Only the fan for the heater inside the coach is electric.

[Roadtrek Adventuous RS1]

Originally Posted by mikeehlert

Have the Nova Kool RFU 6200 in our 2017 Paseo with standard dual AGMs like a prior poster. System Keeps up okay for 36 hours (2 nights) including CPAP, and exhaust fan. Then it needs generator or drive time to get enough for another night in the summer.

I think that your refrigerator draws 4.4 amps per hour??
Have you determined how many hours the compressor is running?

Do you have solar?? Are you pleased with the performance of the Nova Kool??? It's an AC / DC only unit, correct??