New to me Dometic CFX95

[TommyArgh]

I recently bought this fridge and I love it. Im still figuring out its efficiency. However, to test it I had it connected to a X2 Power AGM Group 24 battery. It ran good all day, kept its temperature but with it set at the "low" power warning it ran the battery all the way down to it. I was expecting a little bit more out of it being a "higher end" battery and all.

Does any one have experience with this battery or fridge that can lend some advice?

 

[1leglance]

First that is a big big fridge, and it will always work much better full rather than empty.
Also your battery list as 76 amp hours, of which you really get less than 1/2, so maybe 30 amp hours, so figure the fridge was started up warm, had to run hard to cool down and even on the low power setting it wants to protect your battery.
I would think you actually did well with that battery and that big fridge on that test.

You will find a solar panel will greatly help your fridge setup as you will get "free" power during the day when the fridge is working hardest. Also if you size your panel larger then you will have excess power to cover the fridge and still charge the battery vs a smaller panel that will have trouble filling up the battery at the same time the fridge is drawing power.

 

[TommyArgh]

First that is a big big fridge, and it will always work much better full rather than empty.
Also your battery list as 76 amp hours, of which you really get less than 1/2, so maybe 30 amp hours, so figure the fridge was started up warm, had to run hard to cool down and even on the low power setting it wants to protect your battery.
I would think you actually did well with that battery and that big fridge on that test.

You will find a solar panel will greatly help your fridge setup as you will get "free" power during the day when the fridge is working hardest. Also if you size your panel larger then you will have excess power to cover the fridge and still charge the battery vs a smaller panel that will have trouble filling up the battery at the same time the fridge is drawing power.

That makes me feel better! I am just starting to wet my feet in extra power and renewable energy so I really appreciate your insight.
I do have a Renogy 100w kit that I will be incorporating so that will be phase 2 of my setup. I did also go out and purchase a NOCO Genius Gen1 10A battery charger. I did get it connected and installed onto my battery box. Its currently charging the battery as we speak. My first time around recharging the battery I used a much older charger that was only good for 4amps. Im hoping this will give it a much better charge given its output. One thing that concerns me is that I was told I shouldnt have the fridge plugged in while charging the battery? This also raises more concern when I go to connect the solar panel. Will it be generating too much power that it could damage the electronics in the fridge?

 

[1leglance]

Nope, you can have the fridge plugged into 110v wall power and 12v power at the same time. If I remember Dometic will pull from 110v first but a quick call to customer service will tell ya.
I regularly plug in my vehicle fridge to 110v when at home just to take the load off the battery/solar when it stupid 118deg hot in phx

 

[dcg141]

I have a CFX 65 and recently did a new second battery setup with a group 35 X2 and a Redarc 25 amp DC to DC charger. Mine ran a full 24 hours but I started getting low power lights on my battery monitor but the fridge never changed. I do have my threshold set to low on the fridge. I had to drive everyday during this trip and the Redarc would get the battery back up to full on my monitor after about 30 minutes.

 

[vtsoundman]

My CFX65DZ (used only as a fridge) draws 10- 20Ah /24 hrs depending on external temps and number of times it gets opened and amount of liquid inside. Typical is around 12Ah per 24hrs in 75deg ambient days/ 60 deg nights. More liquid, more stable the temps are.

I have a small USB variable speed fan inside the Dometic that circulates air all the time. I have a 2nd small fan that blows air through the outer coils when the fridge kicks on. These two fans have reduced overall energy consumption 10-20% and results in better(more even) internal temp uniformity.

This 4th of July trip, the van sat from Wed mid morning through Sunday morning - total draw was 85Ah incl fridge, ~20hrs of ham radio, led interior lights, 2 cell phone charges per night (pair of pixel phones), and 2 days of Max Air fan at 20%. I also had a constant 300ma draw from a failing 12V USB charger outlet that I just figured out today (about 25Ah worth). My van has a pair of Full River 6V 225Ah (225Ah @12V) nameplate.

They were abused by previous owner and are currently around 80% (180Ah) of original capacity and are about 3yrs old.

Total time before charging was about 90 hours. No solar was deployed.

Insulation and a few tricks ( fans and some drinks) will help to extend your battery significantly. It also helps to precool all your food 24hrs before running on battery.

 

[TommyArgh]

I have a CFX 65 and recently did a new second battery setup with a group 35 X2 and a Redarc 25 amp DC to DC charger. Mine ran a full 24 hours but I started getting low power lights on my battery monitor but the fridge never changed. I do have my threshold set to low on the fridge. I had to drive everyday during this trip and the Redarc would get the battery back up to full on my monitor after about 30 minutes.

Thats a really nice charger! Unfortunately I have the battery set up as a stand alone requiring a charge from 110v or my 100w panel.

 

[TommyArgh]

My CFX65DZ (used only as a fridge) draws 10- 20Ah /24 hrs depending on external temps and number of times it gets opened and amount of liquid inside. Typical is around 12Ah per 24hrs in 75deg ambient days/ 60 deg nights. More liquid, more stable the temps are.

I have a small USB variable speed fan inside the Dometic that circulates air all the time. I have a 2nd small fan that blows air through the outer coils when the fridge kicks on. These two fans have reduced overall energy consumption 10-20% and results in better(more even) internal temp uniformity.

This 4th of July trip, the van sat from Wed mid morning through Sunday morning - total draw was 85Ah incl fridge, ~20hrs of ham radio, led interior lights, 2 cell phone charges per night (pair of pixel phones), and 2 days of Max Air fan at 20%. I also had a constant 300ma draw from a failing 12V USB charger outlet that I just figured out today (about 25Ah worth). My van has a pair of Full River 6V 225Ah (225Ah @12V) nameplate.

They were abused by previous owner and are currently around 80% (180Ah) of original capacity and are about 3yrs old.

Total time before charging was about 90 hours. No solar was deployed.

Insulation and a few tricks ( fans and some drinks) will help to extend your battery significantly. It also helps to precool all your food 24hrs before running on battery.

That sounds like its a well thought out system. I have several little bugs that I need to work out in my system with insulation being the main one. The fridge and battery setup is in the bed of my truck under a topper. I keep the windows on the topper to help draw some of the heat out. The insulated fridge cover may be in my near future and I also may need to tint the windows on the topper with a better film to help reflect some of those sun rays out. These humid mid-western temps are really putting it to the test.

 

[TommyArgh]

Nope, you can have the fridge plugged into 110v wall power and 12v power at the same time. If I remember Dometic will pull from 110v first but a quick call to customer service will tell ya.
I regularly plug in my vehicle fridge to 110v when at home just to take the load off the battery/solar when it stupid 118deg hot in phx

I was able to connect my 100w solar panel but it didnt seem to help cover the fridges power consumption and keep a charge on the battery. I didnt fully charge the battery the night before because I wanted to test the panels capability. The fridge ran during the day while I was at work. I went out every so often to check the battery level, fridge vitals, and make that the panel was charging. I thought the panel was doing its job but after the sun went down the battery died soon after. As of now I dont have a meter to check how much the panel is putting out and how much that fridge is drawing while the complete system is running. I still have some tinkering to do...

 

[dcg141]

Thats a really nice charger! Unfortunately I have the battery set up as a stand alone requiring a charge from 110v or my 100w panel.

I have a 100 panel and the Redarc is dual input with a mppt charger as well. I never needed to hook up the panel so I'm not sure how well it could have brought back some of the charge or extended the battery's run with the fridge. I actually got the vehicle I now own because there was an off the shelf 2nd battery mount available. Of course there were other deciding factors but that one was high on my list.

 

[1leglance]

A 100 watt panel isn't really 100 watts especially not for the entire day.
In order to get a good test you need to fully charge the battery and get the fridge cold on house current.
Run the fridge from sundownish to sunup and check your battery level.
If your battery is really low you need more battery before you worry about solar panel size.
If your battery is ok in the am then you can get enough panel going to cover the day need plus enough to keep the battery full by the time sun isn't helping the panel anymore till the sun is hitting it again the next day.
Just for example, I have a 300watt residential panel (they are the cheapest) on my camper flat mounted....that means even when the sun is up if I don't have a high enough angle the panel doesn't produce much.
Using my Victron (they make great stuff) bluetooth history app on the phone I can see that my panel really only gives me 180-200 watts due to sun angle, shade, dust, bird poop and all that.

 

[TommyArgh]

A 100 watt panel isn't really 100 watts especially not for the entire day.
In order to get a good test you need to fully charge the battery and get the fridge cold on house current.
Run the fridge from sundownish to sunup and check your battery level.
If your battery is really low you need more battery before you worry about solar panel size.
If your battery is ok in the am then you can get enough panel going to cover the day need plus enough to keep the battery full by the time sun isn't helping the panel anymore till the sun is hitting it again the next day.
Just for example, I have a 300watt residential panel (they are the cheapest) on my camper flat mounted....that means even when the sun is up if I don't have a high enough angle the panel doesn't produce much.
Using my Victron (they make great stuff) bluetooth history app on the phone I can see that my panel really only gives me 180-200 watts due to sun angle, shade, dust, bird poop and all that.

After fiddling with temps that I need on the fridge I was able to get the fridge to run an entire day on just battery and solar, no help from a 110v charge. I was able to get volt readings at the solar charger input, output to the battery, and right at the battery terminals. I was getting about 15-18 volts of energy from the solar panel flat mounted to the roof rack of my truck parked in direct sun with no obstruction from 7am to 4pm at work. In fact the panel charged the battery to full in about 2.5 hours so it was definitely keeping up with the fridge and then some. I do plan on making a mount for the panel to adjust for maximum exposure to try an get a little bit more out the panel as I do plan on adding a couple more electrical components, LED lighting for the inside of the topper and some usb charge outlets.

With that being said it was able to run through the entire night with no issues. I checked the battery levels first thing this morning and it had barely drawn any power. Today I will continue to check the status of the system as I expect it to be fairly cloudy.