Which way, more power, or better fridge?

Trawlercap

New member
D8375F9B-84BB-499A-A6D6-E10765A6774A.jpegWe are currently really enjoying the Lake Havasu and Parker area. Our Sprinter feels like a space ship, is great.
My question: I have a fringe/freezer combo for FM-62DZ Whynter 62 Quart Dual Zone Portable Fridge/ Freezeri like everything about it but the 4.5 amp draw. 2/100 watt panels and one 105 amp house battery is not cutting it, even in ideal Arizona sun.
Do I bump up to 400 watts solar on top and another battery?
I see some fridges use way less (like 1.5 amps) would that be an option, new fridge, leave the rest alone? The rest of our consumption is very low.
So...more power or new fridge? Please shout out if you like yours.
ACA0396B-D03F-4E9E-B281-D4232B7FC324.jpegD8375F9B-84BB-499A-A6D6-E10765A6774A.jpeg
 
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john61ct

New member
Lowering consumption should be the top priority from the design starting point when striving for solar-only living off-grid.

Two or more single compartment Engels all the same size is IMO the best & most flexible solution.

Of course if you already have a genset maybe just save up and wait for the Whynter to break :cool:
 

Graphite Dave

Dave Orton
I have a 85 liter front opening Vitrifrigo, single 300 watt of solar panel with MPPT controller and a single 255 amp-hr AGM battery. No issue getting back to 100% SOC every day with full sun. Even on overcast days I get back to 100%.

You are not going to get a much better chest type refrigerator so your option IMO is additional solar and larger battery capacity. Do you have a MPPT controller? A high voltage panel with a MPPT controller works. MPPT provides additional charging amperage.

Being a front opener I was able to add 2 1/2" of rigid insulation around sides and top and bottom. Glued 2" of closed cell foam to back of the refrigerator. Vitrifrigo has fan style compressor like a chest type refrigerator so power usage is 2/3 of the power required for my sold Sprinter conversion's 80 liter Dometic with a coil condenser on back of the refrigerator.
 

HarryN

Active member
View attachment 128036We are currently really enjoying the Lake Havasu and Parker area. Our Sprinter feels like a space ship, is great.
My question: I have a fringe/freezer combo for FM-62DZ Whynter 62 Quart Dual Zone Portable Fridge/ Freezeri like everything about it but the 4.5 amp draw. 2/100 watt panels and one 105 amp house battery is not cutting it, even in ideal Arizona sun.
Do I bump up to 400 watts solar on top and another battery?
I see some fridges use way less (like 1.5 amps) would that be an option, new fridge, leave the rest alone? The rest of our consumption is very low.
So...more power or new fridge? Please shout out if you like yours.
View attachment 128035View attachment 128036
The electrical system that you currently have installed is what you would use if you didn't have a refrigerator at all. While changing the fridge out might reduce consumption, your system is still going to come out very short. You also have to be careful with the numbers, refrigerator power consumption is rated for I think 70 F, which won't happen for much longer in AZ.

It isn't obvious, but when you have an extremely small battery like that, your dependence on having a large solar array to make up for it increases a lot. I can't imagine that your system is ever fully charging on days when you are using it.

Personally, I think that having the largest possible refrigeration capacity is a great way to enjoy a van. You can store supplies that allow for longer periods of off grid use.

My recommendation is 400 amp-hrs of battery and 400 watts of solar - or as much as you can physically put up on the roof. The absolute smallest system that we build is 160 amp-hrs and I consider it to be a "minimalist" set up.
 

DavidEM

Member
Switching to an MPPT controller will improve your daily solar amp hours a little, maybe 10-15%. Another solar panel will help along with another battery to carry you through cloudy days. Make sure your existing controller is big enough for 400 watts and if not install an MPPT controller good for 35 amps or more.

The Whynter is rather inefficient. Their literature says 75 watts, which is 6+ amps at 12V. This Engle is much more efficient, probably due to better insulation and an optimized compressor: https://www.amazon.com/Engel-Portab...1586443922&sprefix=engle+porta,aps,220&sr=8-7

Their literature says it draws 1-2 amps DC but that is an average. It probably draws 3 amps or so when the compressor is running, but the average is probably 24-48 amp hours daily. Your Whynter probably draws almost double that.

But it is rather expensive so your best solution is more solar panels and another battery.

David
 

Kajtek1

2015 long/tall limo RV 2.1l
Get a pen & piece of paper and start writing down the numbers.
I assume you already have small generator to recharge batteries on cloudy days?
So using it to boost the charge for 2 hr daily with ECO generator would cost you 20 or 60 cents.
Times whatever days you spend boondocking.
Than how much additional solar panel and installation cost?
Dividing the numbers will give you number of years to potentially recoup the cost of solar panels.
If it comes to more than 30 years >>> forgetaboutit
 

Zundfolge

1-2-4-5-3
Get a pen & piece of paper and start writing down the numbers.
I assume you already have small generator to recharge batteries on cloudy days?
So using it to boost the charge for 2 hr daily with ECO generator would cost you 20 or 60 cents.
Times whatever days you spend boondocking.
Than how much additional solar panel and installation cost?
Dividing the numbers will give you number of years to potentially recoup the cost of solar panels.
If it comes to more than 30 years >>> forgetaboutit
Van accommodation considerations typically factor in more than simply cost. 30 year ROI's are more of a residential consideration, not so much on a van. Van's have slipperier factors to consider like, oh let's call it the convenience coefficient :) Additionally, carrying a generator and fuel is an entirely different approach, and loud and smelly.

(not to mention 200W of solar is cheap nowadays)

Unfortunately 105AH is truly only about 50 usable AH in what I'm at least assuming is an AGM or FLA battery? So if you prefer to stick with that battery chemistry then yes, you could add another and have an effective 100AH of usable battery. You say your usage is low, basically only the fridge, and since you're talking about possibly rearranging your electrical setup it's worth asking if you might plan on any other electrical upgrades in the future? Specifically, a diesel heater or anything else? Because if you absolutely know that your foreseeable needs won't change, then it's pretty simple math to get you where you need to be - consumption per day; capacity needed; solar (or other input) to replace it.

Either way that's the math really, but even if you might add a heater or something else you oughta plan for it now. Redoing an electrical system is expensive, please don't ask me how I know. Or do, I like learning from mistakes. My first van electrical iteration before I was very familiar with this stuff was a single 105AH AGM battery. That was before I was trying to power even a fridge, and it was insufficient. Was using it mainly to power a 900W electric kettle, without knowing that asking 1C out of a battery+1000W inverter setup was not a recipe for success. Basically just redlining my setup when I used it. Second iteration was 225AH FLA with 200W solar input. (Now it's a 170AH LiFePo4)

200W solar on a van with almost any battery setup is insufficient. Unless you have the ability to tilt your panels to the sun, which in many NA latitudes will almost double the panel output, you'll need more solar pretty much no matter what path you choose forward IMO. Get 100-200W more up there. You're probably getting that battery somewhere around 75% SoC overnight I'm guessing? If it was running half of the time overnight you're looking at 27AH consumption over 12 hours. Then if you get 6-ish hours of good solar coming back in throughout the day that's around 36AH back in (assuming 4.5 amps coming in, but you haven't posted your numbers, and we don't know if you have battery monitoring or what your setup is, PWM vs. MPPT etc.) except let's say half of that is being used by the fridge during the day so you replace 18AH into the bank, starting your night with 87AH, then it gets depleted another 27AH overnight, and you start your solar day somewhere around 57% capacity, and on and on until you post on the forum about the best way forward.

Well honestly, both things you are proposing are necessary. Speaking of ROI's my option if I were in your shoes would be to beef up the electrical system first. 200W more and double your battery capacity. Then you can at least expect to keep up with your fridge, and have some extra power (which you'll need for cloudy days/trees/large spaceships etc). Ride the fridge you have into the ground, and replace it with something more efficient.

Brings up a question, how old is your current battery? If it's more than 1-2 years it may be unadvisable to add one, effectively bringing SoH (State of Health) of your new battery to the SoH of your old battery, reducing its lifespan some...

...My recommendation is 400 amp-hrs of battery...
Is that not pretty serious overkill if their stated needs are only a fridge? I like room to grow personally, and am all for more capacity, but 400AH is getting into more serious electrical needs than a preferred 1.5A draw fridge...
 
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Midwestdrifter

Engineer In Residence
I suggest testing the fridges total consumption. You need duty cycle and power to determine watt-hours or amp-hours.

You very well could just need a larger battery. 200W of solar should support a 60 liter fridge, but depends a lot on what other power consumers you have. A 100 lead batter is probably too small if you are powering other loads.
 

gltrimble

Well-known member
I suggest testing the fridges total consumption. You need duty cycle and power to determine watt-hours or amp-hours.

You very well could just need a larger battery. 200W of solar should support a 60 liter fridge, but depends a lot on what other power consumers you have. A 100 lead batter is probably too small if you are powering other loads.

Accurate analysis. According to the manufacturer’s data the Whynter is a very efficient chest cooler on par with an Engle. When used as a refrigerator in typical conditions it should consume less than 1.5 amps per hour, double this if used as a freezer. I would start by verifying the Whynter’s consumption using an inexpensive energy monitor

200 watts of solar should also be sufficient in most conditions to operate a fridge 24/7. Assuming the fridge and solar are working properly, I would invest in a second battery. A second battery gives you a buffer for excessive fridge use and poor weather.
 

marklg

Well-known member
There have been a lot of suggestions here, some conflicting. You need to measure your specific usage under your conditions with a amp hour / watt hour meter. Otherwise, you will not know what you personally need. Many solar charge controllers will tell you amp hours / watt hours if they have a display. That will tell you how much you are adding back from solar. Everyone's usage / fridge insulation / outside temperature is different. You need to know your numbers. Otherwise it is just a guess.

This will work for 12V systems. It is limited in how much current can go through it, so it can't be in series with an inverter most likely, but it will be good for measuring the fridge and your other medium power stuff.

https://www.amazon.com/gp/product/B0090YW78U

If you measure your consumption for a day or better yet, a few days. In amp hours, you likely want a battery with 2-3X that so you can go through cloudy days without having to charge some other way. A lead acid battery can only discharge to about 50%, so it needs to be twice as big as what you determine you need.

You need to measure what your solar system produces per day. Solar panel output is a big lie. None of them actually produce what they say. You have clouds, shade, sun angle, dirt, etc. Then you should be able to make up what you use in less than a day. That will again allow for cloudy days.

My system consists of 400 aH of LiFePO4 batteries. That will last me three days of max consumption, fridge, microwave, toaster, Keurig and a 500W Ham Radio station. My batteries have built in monitoring of amp hours used.

My solar system consists of two panels on the roof that will keep up with the fridge only. I have four additional panels that can be thrown up on the awning when we stop, for a nominal of about 635W. That system under real conditions of partial tree cover can charge my batteries in about 1 1/2 to two days. So I can stand one or two cloudy days in a row and then get a full recharge. We spent a week in Yosemite last summer and did not need to use the generator at all.

I replaced our Propane fridge with a Vitrifrigo 115L fridge. It works way better, especially when it is 115 outside. But again, that depends on your environment. It was the right choice for us.

Regards,

Mark
 

HarryN

Active member
Small battery / small solar systems work great - until a couple of cloudy days. A 400 amp-hr x 12 volt battery system will help ride through 3-4 days of poor weather.

If you are going to be hanging out stationary in AZ for long, it might make sense to buy a roll out panel and put it into the sun.

You have to decide if your goal is for things to work "on average" or "99+% of the time".

As a practical matter, most people find more and more uses for power over time, not less.

If the risk of loosing the food in your fridge or not having heat once in a while is acceptable, then all kinds of things are possible. My customers complain when this happens.

If you have an active battery to battery charge capability and go driving for an hour a day in the morning, that also helps.
 

marky

New member
I have experience with two Engels, both not good. In my van we had built in drop-in engel (top loading). It quit after 4 years. Since it was built in and the engel no longer made it I had to build a fridge to fit the space. It has a stainless steel liner I had fabricated and 2 inches of foam insulation. It uses an Isotherm marine conversion system, model 2007. The key to efficiency is good air circulation, that means ducting the cooling air directly to the condenser fan. The house battery is two 6V lifeline batteries in the space below the passenger seat, 300amp hours. No solar panels or charger. We are moving around enough that the alternator keeps them charged.

It will freeze the box if we want. We turn it off at night because we do not want to hear it, even though it is quiet. The box holds well overnight even in the summer.

The other engel is a front loading typical RV fridge that is a piece of s**t. The door hinges let the door droop and catch fail, the air circulation is very poor. Runs all the time and the beer is not ice-cold. So we are in the process of again building our own refrigerator/freezer from the ground up and will use an Isotherm system.

If you have good batteries, an efficient fridge and you are driving say every third day forget the solar panels.
 
Accurate analysis. According to the manufacturer’s data the Whynter is a very efficient chest cooler on par with an Engle. When used as a refrigerator in typical conditions it should consume less than 1.5 amps per hour, double this if used as a freezer. I would start by verifying the Whynter’s consumption using an inexpensive energy monitor

200 watts of solar should also be sufficient in most conditions to operate a fridge 24/7. Assuming the fridge and solar are working properly, I would invest in a second battery. A second battery gives you a buffer for excessive fridge use and poor weather.
Yes Yes and Yes.

Additionally, the Whynter fridge is absolute garbage. It is the same as Edgestar- see here: https://sprinter-source.com/forum/showthread.php?t=78726&highlight=edgestar
You should plan for that thing to fail within the next year or two. Sorry for the slightly off topic, but I like to take every opportunity to bash these cheap garbage companies because they caused me a lot of headache and are polluting our planet with their disposable trash.
 

Jmolan

New member
Thanks to everyone, wow, I am blown away at the response, truly. A lot of brain power and experience here. With your good question I realize how I am limping along with "bare bones" and I need to upgrade. Pics below are the location of the single house battery the Victron monitor showing over 2 amps going in (afternoon with fridge/freezer running. And what I think you all are referring to as a MPPT Controller? I got the Renology kit with 2/100 W panel's and this controller.
Question: Can I hook two more panels and use this same controller? Or get a separate one for the new panels.
I would love to run this big dog: https://www.batterymart.com/p-pc180..._QAeNW0cga8cURLb_cet4fF9lcG7Z15REcaAiCM8P8HAQ I believe I have a place it would fit.

Am I getting closer? 200 more solar watts, a big ass battery?

I run a Espar under seat heater, A fantastic fan, 400 w inverter to charge our E bikes while driving down the road.

Very seldom does any of this make it through a night with out running low.

Thanks again, this is really fun for me to think I can dig my way out without too much pain..:)

IMG_7732.jpg

IMG_7736.jpg

IMG_7733.jpg
 

Jmolan

New member
Yes Yes and Yes.

Additionally, the Whynter fridge is absolute garbage. It is the same as Edgestar- see here: https://sprinter-source.com/forum/showthread.php?t=78726&highlight=edgestar
You should plan for that thing to fail within the next year or two. Sorry for the slightly off topic, but I like to take every opportunity to bash these cheap garbage companies because they caused me a lot of headache and are polluting our planet with their disposable trash.
Hey...but how do you really feel about it?..:) Thanks, I can't get the link to work but I will try again. Appreciate it.
 

Jmolan

New member
I have experience with two Engels, both not good. In my van we had built in drop-in engel (top loading). It quit after 4 years. Since it was built in and the engel no longer made it I had to build a fridge to fit the space. It has a stainless steel liner I had fabricated and 2 inches of foam insulation. It uses an Isotherm marine conversion system, model 2007. The key to efficiency is good air circulation, that means ducting the cooling air directly to the condenser fan. The house battery is two 6V lifeline batteries in the space below the passenger seat, 300amp hours. No solar panels or charger. We are moving around enough that the alternator keeps them charged.

It will freeze the box if we want. We turn it off at night because we do not want to hear it, even though it is quiet. The box holds well overnight even in the summer.

The other engel is a front loading typical RV fridge that is a piece of s**t. The door hinges let the door droop and catch fail, the air circulation is very poor. Runs all the time and the beer is not ice-cold. So we are in the process of again building our own refrigerator/freezer from the ground up and will use an Isotherm system.



If you have good batteries, an efficient fridge and you are driving say every third day forget the solar panels.


Good info thank you sounds like you kept at it till you got a good system. Bravo!
 

Jmolan

New member
Accurate analysis. According to the manufacturer’s data the Whynter is a very efficient chest cooler on par with an Engle. When used as a refrigerator in typical conditions it should consume less than 1.5 amps per hour, double this if used as a freezer. I would start by verifying the Whynter’s consumption using an inexpensive energy monitor

200 watts of solar should also be sufficient in most conditions to operate a fridge 24/7. Assuming the fridge and solar are working properly, I would invest in a second battery. A second battery gives you a buffer for excessive fridge use and poor weather.
I watched it today, fridge was at 33º freezer at 12º it was using between 2.5 and 3.0 amps. I get between 4.5 and 5 amps when it is working hard.

Good idea on the battery https://www.batterymart.com/p-pc180..._QAeNW0cga8cURLb_cet4fF9lcG7Z15REcaAiCM8P8HAQ
 

Jmolan

New member
There have been a lot of suggestions here, some conflicting. You need to measure your specific usage under your conditions with a amp hour / watt hour meter. Otherwise, you will not know what you personally need. Many solar charge controllers will tell you amp hours / watt hours if they have a display. That will tell you how much you are adding back from solar. Everyone's usage / fridge insulation / outside temperature is different. You need to know your numbers. Otherwise it is just a guess.

This will work for 12V systems. It is limited in how much current can go through it, so it can't be in series with an inverter most likely, but it will be good for measuring the fridge and your other medium power stuff.

https://www.amazon.com/gp/product/B0090YW78U

If you measure your consumption for a day or better yet, a few days. In amp hours, you likely want a battery with 2-3X that so you can go through cloudy days without having to charge some other way. A lead acid battery can only discharge to about 50%, so it needs to be twice as big as what you determine you need.

You need to measure what your solar system produces per day. Solar panel output is a big lie. None of them actually produce what they say. You have clouds, shade, sun angle, dirt, etc. Then you should be able to make up what you use in less than a day. That will again allow for cloudy days.

My system consists of 400 aH of LiFePO4 batteries. That will last me three days of max consumption, fridge, microwave, toaster, Keurig and a 500W Ham Radio station. My batteries have built in monitoring of amp hours used.

My solar system consists of two panels on the roof that will keep up with the fridge only. I have four additional panels that can be thrown up on the awning when we stop, for a nominal of about 635W. That system under real conditions of partial tree cover can charge my batteries in about 1 1/2 to two days. So I can stand one or two cloudy days in a row and then get a full recharge. We spent a week in Yosemite last summer and did not need to use the generator at all.

I replaced our Propane fridge with a Vitrifrigo 115L fridge. It works way better, especially when it is 115 outside. But again, that depends on your environment. It was the right choice for us.

Regards,

Mark
Thanks, That was well written and easy to understand. I've been watching the monitor closer today. Looks like peak of 7.5 amps middle of the day from the panels. Much less on both sides of noon.

I am thinking anther 200 solar and 100 or 200 battery.
https://www.batterymart.com/p-pc180..._QAeNW0cga8cURLb_cet4fF9lcG7Z15REcaAiCM8P8HAQ
 

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