Dometic cfx 95 DZW

[David Riechman]

Hi, I have an issue with keeping the 12 v working when frig is connected. The 12v cord gets hot after several hours then the dometic frig gets an amber light. If I disconnect the frig and wait till the cord cools off and plug it back in it works again. I have an Opus trailer with 3 12v plugs and all 3 do the same thing. I called Domeyic and was told I had a ground problem. I had the 3 12 v plugs checked and could not find a problem. The frig works just fine when plugged into 120v. The frig will run fine in late evening when the weather is cooler. Any help on what the issues are would be appreciated.

[Kirk W]

Welcome to the Escapee open forums!

An I correct in assuming that your portable refrigerator cord is getting hot only when it operates from the 12V power source in the heat of the day. While I have no experience with any of the small, 12V compressor type of refrigerators, I do have more than 40 years of electrical service background. Based on that experience I am betting that the problem is your refrigerator is running too long at too high an amperage for the wire size of the cord. If the power plug is overheating, then it could be that the problem is the outlet and not the cord but one of them is exceeding the capability of it's construction. A cord will overheat when the current load is too much for it's capability and it begins to act like a resistance due to the excess load. The power required by the compressor is in watts, which is the voltage multiplied by the current. That means that at 12V it will require twice as many amps as it would at 24V and ten times the amps of a 120V power supply. In addition, as you draw power from your batteries the voltage actually changes, starting at fully charged with 13.6V and slowly falling with 10.5V when near maximum useful output. That means that if your refrigerator needs 75 watts of power it will draw 5.5A when the battery is fully charged and 7.2A when the battery falls to 10.5V.  The specs for the refrigerator calls for an input of 9.2A so I suspect that peak requirement is more than the math shows. 

In reading the instructions that the operator's manual has, I see that it has a voltage monitor to prevent completely discharging of the battery. Might that be what is happening to your refrigerator?

Quote

When operating with the battery, the display switches off automatically if the battery voltage is low. The LED “P” flashes orange.

Another issue might be the temperature where the refrigerator is when traveling. From the operating manual:

Quote

Ambient temperature: +16 °C to +43 °C (+61 °F to +110 °F)

That makes a peak operating temperature issue a possibility, especially if the 12V use in in an enclosed area that is not air conditioned. 

[oldjohnt]

David, obviously if the cord gets much too HOT, its drawing more current then its rated for. Typically if the cord has the correct overcurrent protection (fuse or breaker) that shouldn't happen. If you're running on 12 Volts versus 120, that's like 10 times more current and like 11 times the battery amps versus 120 amps if you're using an Inverter........

Is this a three way 12 VDC,,,,,,,,,120 VAC,,,LP Gas fridge or what ???

Is it an Absorption RV type of fridge or a compressor powered ??

Is it a 12 VDC Compressor fridge ????

Are you powering it using straight 12 VDC or is it running on 120 VAC supplied by your battery and an Inverter ???

John T

[mptjelgin]

It looks like this compressor powered unit is rated to draw almost ten amps, which isn't trivial especially when pulled continuously.  Many cigarette style plugs in trailers are rated for 3 - 5 amps.  They are sized for things like phone chargers and other low-draw items.

When I had a small inverter in my last trailer I wired in a special, heavy duty 12 volt plug with much heavier wire connected directly to the battery to handle the load. 

I would suggest that you consider a more direct, heavier gauge connection from your batteries to the cooler. 

Edited July 4, 2020 by mptjelgin

[David Riechman]

Thanks for the info,  I was thing that may be the problem since the cable was getting hot. what gage wire should be used and where would you get a 12v connection that would handle the larger wire connection.

[Kirk W]

3 hours ago, oldjohnt said:

Is it an Absorption RV type of fridge or a compressor powered ??

The model that he has is a compressor type, portable refrigerator capable of power by 12/24V-DC or 120/240V-AC power. His problem was when operating on 12V power from his popup travel trailer. 

1 hour ago, David Riechman said:

what gage wire should be used and where would you get a 12v connection that would handle the larger wire connection.

I think that I would hesitate to just replace the wire without some input from the manufacturer. The cord that it came with should be sufficient to carry the load unless there is some sort of problem. I am rather surprised that the unit is shutting down without blowing the fuse that is in the power plug, unless the problem is that the under voltage sensing is triggering, which could be the cause of the flashing light, according to the operating manual. The other thing that reading the manual brings to mind that could possibly cause it to draw too much current is poor ventilation. Is it in a place with ample room for air movement? Have you measured the voltage that is available when the problem happens? Is the unit still under warranty? 

[oldjohnt]

David, if indeed the unit requires 10 amp at 12 Volts, I would install no less then a 20 Amp rated 12 VDC power outlet available at E Trailer or Amazon and a ton of other outlets no big deal. I would wire it with 10 gauge wire to reduce voltage drop, even though 12 could suffice, with proper overcurrent protection (Fuse or DC circuit breaker) at the source. This is an Easy Peasey inexpensive method to power any 12 VDC appliance that requires 10 amps. You can even get a 12 VDC power outlet that has a volt meter built in to monitor voltage at the load, which if low, can cause problems, excess current and overheating. DON'T OPERATE AT LOW VOLTAGE !!! Insure you have adequate voltage AT THE LOAD....... 

20 Amp 12 VDC Power outlets:  https://www.bing.com/search?q=20+amp+12+volt+power+outlet&PC=U316&FORM=CHROMN

If the wire ampacity is marginal and/or the length is to long such can cause overheating. Similar a power outlet that's rated too low  (like a wimpy 100 watt unit) can cause problems so check out a 20 or even 30 amp (if available) 12 VDC power outlet with big enough gauge wire (prefer even bigger then absolutely necessary) to the battery source. If the unit has a compressor or other problem ??????? that could be the cause of excess current. Maybe the wiring is sufficient but the unit is at fault ?????????  

Another option is to HARD WIRE the fridge to your house batteries to avoid any connection or power outlet problems and/or voltage drops

John T

 

[Kirk W]

On 7/4/2020 at 8:01 PM, oldjohnt said:

Another option is to HARD WIRE the fridge to your house batteries to avoid any connection or power outlet problems and/or voltage drops

John T

Let me suggest that you slow down some and read the manual for this portable refrigerator/freezer.

Edited December 31, 2022 by Kirk W

[mptjelgin]

The Manual notes that the unit contains a battery monitoring system that can be set to Low, Medium, or High.  Set on "High" the unit shuts off at 11.8 volts which is pretty sensitive.   "Medium" shuts off at 11.4 volts and "Low" shuts off at 10.1 volts. 

Do you know what setting your battery monitor is on?  If on "High" I would try it on "Medium" and see it things work better.  If on "Medium" you could try "Low", but I would not advise drawing a battery down to 10.1 volts as a normal operation. 

From what you've described your battery monitor is turning the unit off due to low voltage.  It could be that the "High" setting is unnecessarily sensitive, or as has been mentioned previously, your 12V plugs are not adequate for the load and a voltage drop within your system is causing a problem.

[oldjohnt]

7 hours ago, Kirk W said:

Let me suggest that you slow down some and read the manual for this portable refrigerator/freezer.

Slow down ??? NOT ME that's for "old" guys lol

I cant get the manual to open grrrrrrrrrrrrrrrrrrrrrr ??????? so I have to rely on what the OP has stated.

Regardless, if and where possible, I always prefer a hard wire connection versus any inferior possibly insufficient rated potentially voltage dropping plug that might, FOR WHATEVER REASON ??? overheat.   If its overheating  the wire may be too small,,,,,,,,,,Or the connection isn't adequate rated,,,,,,,,,,,Or its drawing too much current,,,,,,,,,And/or the overcurrent protection device isnt functioning properly .  Regardless, Id suggest more then called for wire size to reduce line voltage drop plus a connector (if not hard wired) rated higher then the expected current draw, but hey that's just me............ 

In 49 years or RV ownership and as a used dealer I just saw too many plug and connection methods fail which is why I prefer a hard wire IF AND WHERE POSSIBLE, SUBJECT TO USE LOCATION AND NEED FOR PORTABILITY (IE its NOT for every application !!!!).  Perhaps many failed because they used the cheapest unit available that WAS NOT SUFFICIENT RATED yet sure could still work especially when new and not much use. That's true in RV manufacture OTHER THEN ELECTRICAL grrrrrrrrrrr.   Also perhaps a light duty maybe 100 Watt Power Outlet may have been installed fine for low power electronic charging BUT NOT for a higher current fridge or other such application ??? I just don't know whats there,  its ratings and fridge requirements, so I cant judge the best connection method, sorry.   

Hope this helps

Thanks Kirk, best wishes, try posting another link for the manual ??? I will give it a try and let you know. 

PS I'm headed your way in a few weeks, it wont be too hot down there will it lol

John T

 

Edited July 5, 2020 by oldjohnt

[oldjohnt]

20 hours ago, David Riechman said:

what gage wire should be used and where would you get a 12v connection that would handle the larger wire connection.

PS David, in addition to the 12 Volt 20 Amp DC Power Outlets I posted above, here are some 25 and 30 amp rated units

https://www.amazon.com/Power-Source-12V-Outlet-Housing/dp/B011TN9V5Q

It never hurts to err on the caution side and oversize where electricity is concerned, especially if overheating occurs, and bigger wire means less line voltage drop. Same as above subject to current and wire length, Id still use at least 10 gauge Wire. Of course, voltage at the source (battery bank) must also be adequate, if that's too low there can be a problem even if the fridge itself is fine !!!!!!!!!!!  Always check for low battery voltage when 12 volt device problems occur.  

Let us know what happens   

John T

 

Edited July 5, 2020 by oldjohnt

[Kirk W]

3 hours ago, oldjohnt said:

I cant get the manual to open grrrrrrrrrrrrrrrrrrrrrr ??????? so I have to rely on what the OP has stated.

I did a Google search on "Dometic cfx 95 DZW manual: and the link that I tried to post goes directly to Dometic and downloads the operator's manual automatically. Try this link from Cool Tech Leisure that comes from the UK but seems to work better. The Google search gets several other sources.

If he were to hard wire it that would mean it was no longer portable and might also mean he could not use the cable for 120V power when available. 

 

Edited July 5, 2020 by Kirk W

[oldjohnt]

58 minutes ago, Kirk W said:

Try this link from Cool Tech Leisure that comes from the UK but seems to work better.

YESSSSSSSSSSS that link worked immediately !!!!!!!!!!!!!!!!!!!! THANKS 

Maybe if his battery voltage PLUS the actual voltage at his unit is within spec ABSENT ANY hot cords or excess line voltage drop or any weak under rated voltage dropping heat producing connections, be it a 12 VDC Power Outlet and Plug or more permanent hard wire type (if feasible based on use, location and portability issues) HECK IT MAY WORK BETTER ??????????   I'm just the type that (based on years of experience) if any device used a 12 Volt DC Power Outlet and Plug, regardless if the manual specified a lighter duty might suffice, Id probably stick a 20 or 30 amp rated unit in there with heavy gauge 10 or more wire ran to the battery !!! 

I think I saw a review of that or a similar unit on You Tube a while back, I will look later 

Hey we all try our best, that's all one can ask. I just enjoy helping people and figuring these things out lol

A joy sparky chatting with yall, best wishes

John T

 

 

Edited July 5, 2020 by oldjohnt

[Navigator]

I have a CFX3 95DZ connected to a 420ah 8D wet cell 12V battery bank. I have a few questions. With the unit completely full on both sides I set the temperature at 5F.
 

Will I save amp hours if I adjust the smaller compartment to 10F and leave the other side at 5F.

 

When reading the Bluetooth read out I see Amp Hours  would I combine both sides amp hour reading to get a total amp hour consumption.

 

I bought the cover Accessory but haven’t been using it. The freezer is located inside a structure with and average Ambient temp of 70 F. If I use the cooler cover will it improve the efficiency of the cooler.

 

 

[Kirk W]

1 hour ago, Navigator said:

Will I save amp hours if I adjust the smaller compartment to 10F and leave the other side at 5F.

It would decrease the use by only a very little to make such a small change. If you were to use one as a chill box with temperatures in the high 30°F range that would make a noticeable difference.

1 hour ago, Navigator said:

If I use the cooler cover will it improve the efficiency of the cooler.

If it is not exposed to the sun it isn't likely to make a noticeable difference.