Fridge cycle

[WandringKnight]

I've had an Alpicool 16L for nearly 5 years. Its been running well all that time, but I'm noting a larger draw we'll it runs.

The batteries are full at 13.6v+, but when the fridge kicks on, it drops to 9.5v or less. The protection kicks in and powers off the fridge.

I've shortened the 12v socket wire that runs from fuse block to fridge, but I'm hesitant to shorten the cable that came with the fridge.

Not sure how to proceed.
Blow out fridge vents?
Replace power cord?
Get a new fridge?

 

[rruff]

Check all your connections, and if necessary get a multimeter and see if you can determine where the bad connection is that is causing the voltage drop. It's possible that the fridge itself has an issue, but more likely something in the wiring. And if those wire lengths and sizes worked for years, then they don't need to be enlarged or shortened! The issue would be a broken wire, or more likely just a poor connection.

 

[maki2]

Before you replace the cord there is something you can try. …As daily told to students by the teacher in the computer repair course I took at University..Always check the physical connections FIRST when analyzing this type of issue.

It is typically the 12v connectors on the refridgerator cables that came with the fridge, either the socket or the plug, that cause refrigerator electrical issues. The plug end is usually the culprit for problems. It has two metal prongs on the sides and a metal tip and any one of those three can get jammed up and fail to make a really good connection. So start your trouble shooting by taking that plastic tip end apart end apart, inspecting, tweaking the bends on the two metal strips on the sides if needed. But it is most often the tip that is the one not making good contact. It might be binding up in the hole in the plant that it moves in and out of. I found that to be the issue fr ongoing connection issues recently on a plug of that type. If so a small needle file or rolled up piece of sand paper can slightly enlarge and clean up any rough edges inside the hole in that plastic housing the tip passes through. Then also remove that metal tip and GENTLY stretch that spring that pushed on the metal top a very small amount to allow it to make firm contact. . Also remember that when you insert that plug into the socket to gently rotate it a quarter or so distance. That small rotational turn is tequired for a firm electrical connection.

When driving on the road over time vibrations can loosen up those connectors so you can’t just plug it in once and just forget it. That style does require some ongoing maintenance. Many people switch to using other types of connectors that lock together and are not as prone to self disconnection issues from vibration stresses.

I was for many years a professional assembler of a great many items large and small. So my eyes and brain are trained by years of experience to notice even the little stuff such as the inside of a hole not allowing a smooth passage or a contact pin out of alignment, a spring that is overly compressed, corrosion, etc. But anyone can train themselves to LOOK VERY CLOSELY AND ANALYZE assemblies and physical connections. It will become a reliable trouble shooting habit with a small amount of consistent practice. Start with the inspection of the connectors.

 

[abnorm]

The batteries are full at 13.6v+, but when the fridge kicks on, it drops to 9.5v or less. The protection kicks in and powers off the fridge.

Nice tips Ruff and Maki.................I think the Battery is "Dead" or rather asleep

Knight.....I guess that's Lithium and the "protection" the BMS ?......OR ?

Maybe the battery got too low and protection put it to sleep and now needs a "Reset"...........

I keep a 14.5 Volt 20 amp charger (powered by my generator) made for Lithium to KickStart a depleted battery.....just a little charge wakes it up to accept normal charging methods.............YMMV

 

[WandringKnight]

The simple fixes are often the winner. I snugged all the screws and bolts, reseated the plugs, and its purring at 11.3v. I'm not sure why it shows such low voltage. The battery is currently on float at 14.5v. I don't think the fridge ever displays the correct battery voltage. Oh well.

Thanks for all the come backs.

 

[maki2]

Glad it got sorted out without any major repair or replacement of parts required!

Once again proving my professor’s advice for “always check the physical connections first” was and still is an excellent time and stress saver!

 

[rruff]

The simple fixes are often the winner. I snugged all the screws and bolts, reseated the plugs, and its purring at 11.3v. I'm not sure why it shows such low voltage. The battery is currently on float at 14.5v. I don't think the fridge ever displays the correct battery voltage. Oh well.

I was wondering after reading abnorm's reply... I assumed you were looking at a voltage reading on the fridge itself, not the battery... and that the fridge has a switch that stops it running if the voltage is too low. Is that right? If the battery had an issue I figured you notice that other things weren't working, either...

I'd guess you still have a poor connection or bad wire somewhere. Voltage is enough, but that's a big drop. If it's true, then when the battery is less full, you'll likely cut out again. BTW, is this LiFe or lead acid?

A multimeter is a good tool to have... even the cheap ones tend to be pretty accurate... and then you can isolate where the problem is, or confirm that there isn't one.

 

[WandringKnight]

I was wondering after reading abnorm's reply... I assumed you were looking at a voltage reading on the fridge itself, not the battery... and that the fridge has a switch that stops it running if the voltage is too low. Is that right? If the battery had an issue I figured you notice that other things weren't working, either...

I'd guess you still have a poor connection or bad wire somewhere. Voltage is enough, but that's a big drop. If it's true, then when the battery is less full, you'll likely cut out again. BTW, is this LiFe or lead acid?

A multimeter is a good tool to have... even the cheap ones tend to be pretty accurate... and then you can isolate where the problem is, or confirm that there isn't one.

Rattling down forest roads all year, screws are bound to loosen up.

 

[maki2]

Rattling down forest roads all year, screws are bound to loosen up.

If the screw threads are not themselves part of an electrical contact you can use thread locker fluid on them to inhibit the movement of the screw getting loosened by vibrations. I do recommend you be sure which type of thread locker you use. It comes in two versions. One type makes the screws REMOVABLE with a bit of firm force. That would be my suggestion for normal applications in Van Builds. The other type would be considered a permanent bond and applying it can make it nearly impossible to remove the screw.

There are a number of brands. You will often see little tubes of it hanging in the hardware sections in stores. The photo shows the Locktite company removable thread locker. A little dab on an area on the the thread does the job which is why the bottles of this product are very small.