Xantrex Battery Charger Overheating - Frigoboat Fridge

[Sailormannn]

Might have the solution ...

Xantrex confirmed to me this morning that the fan on the bottom of the unit is an intake fan and not an exhaust fan.

On my unit hot air blows out of the intake vent suggesting the fan is operating as an exhaust fan. This may explain why the fan can't keep up with cooling the charger.

Question now is whether there are a bunch of chargers simlarly impacted or if mine an isolated case. I was planning to seek an over-the-counter replacement, but if there are a bunch of units impacted, finding one that works properly might be a problem.

[motion30]

Saliorman
These are the types of problems that caused me to sell the new replacement true charge xantrex sent me as a replacment I now have iota chargers and dont need to think them at all

[Captain Bill]

Originally Posted by Sailormannn

Might have the solution ...

Xantrex confirmed to me this morning that the fan on the bottom of the unit is an intake fan and not an exhaust fan.

On my unit hot air blows out of the intake vent suggesting the fan is operating as an exhaust fan. This may explain why the fan can't keep up with cooling the charger.

Question now is whether there are a bunch of chargers simlarly impacted or if mine an isolated case. I was planning to seek an over-the-counter replacement, but if there are a bunch of units impacted, finding one that works properly might be a problem.

Sailormannn, I looked over the thread and saw that you replaced the charger once, though I didn't see how long ago this was. Is your unit still in warranty. Clearly putting the cooling fan in backwards is a defect in workmanship. If it's not under warranty it's probably pretty simple to open the unit and turn the fan over. If you don't feel comfortable doing it yourself any local electrical shop should be able to do it. If you do it yourself just remember that the unit is likely to have some large capacitors in it that will hold a charge even after the power is disconnected, so stay away from them.

While a reversed cooling fan is a bit of an issue, I don't understand why it would only overheat when the fridge was running. I fear this may not be the entire source of your problem.

[DeepFrz]

Another worrisome thing is why the fan stops when the over temp light comes on! Surely the over temp. condition should boost the fan speed instead.

[Sailormannn]

The charger 2nd charger has only been in the boat a week so it's warranty for sure. I'm trying to get Xantrex to ship me a new unit direct and avoid the hassle doing an exchange. Not sure I really want to open this thing up and mess around with it. I don't think the temp controller in the unit is right either as the fan should stay on when its overheating not shut off.

The unit starts to overheat after its been running for a while. Sometimes this take 30mins or even an hour suggesting it is an overheat situation. I'm going to run some more tests on the DC wiring and see if there are any bad connections.

[DotDun]

Originally Posted by DeepFrz

Another worrisome thing is why the fan stops when the over temp light comes on! Surely the over temp. condition should boost the fan speed instead.

Just a guess - the whole system shuts down on an overheat alarm.

[Sailormannn]

Originally Posted by DotDun

Just a guess - the whole system shuts down on an overheat alarm.

It actually is still charging while the overheat warning light is flashing. I haven't let it go into "fault" mode where the red warning light stops flashing and stays on all the time. According to the manual, when the warning light stays on, it is in fault and charger stops charging. At the that point the fan is supposed to still be running. The manual says to leave the AC on so the fan cools the unit down.

WIth my charger the warning light flashes and the fan stops running.

Xantrex support told me to call back when their California office opens and see if they will authorize shipping me a new unit immediately.

[Sailormannn]

Originally Posted by Sailormannn

Might have the solution ...

Xantrex confirmed to me this morning that the fan on the bottom of the unit is an intake fan and not an exhaust fan.

On my unit hot air blows out of the intake vent suggesting the fan is operating as an exhaust fan. This may explain why the fan can't keep up with cooling the charger.

Question now is whether there are a bunch of chargers simlarly impacted or if mine an isolated case. I was planning to seek an over-the-counter replacement, but if there are a bunch of units impacted, finding one that works properly might be a problem.

Xantrex is sending me a new unit ... will report back once it's in and installed. Feel like I'm finally getting some where.

[Sailormannn]

Here's the news; the problem continues.

New unit arrived on Friday from the factory and was installed today. The installer let it run with the fridge, lights and instruments off charging the batteries and everything looked good. However with the refrigerator on and drawing < 3 amps (showing 10% output on the charger) after about 20 mins or it started flashing high charger temperature warning. I sat beside the charger for the full 20 mins or so and the fan didn't come on once to try to cool the unit. The unit felt warm to touch when it signaled the temperature warning.

I turned the charger off and let the refrigerator run off batteries for 30 mins and the unit was cooling cycling on and off a few times. (draw 3.5A at start up and settles around 2.8A).

I then turned the fridge off and turned the charger on. The fan immediately came on for 10 mins or so. The charge light on the unit was displayed and the remote panel indicated 20% charging output. After 10 mins or so the unit settled back into float stage. The fan stopped and unit indicated <5% output.

I'm at a total loss to explain what's wrong. It must be related to the refrigerator circuit somehow. Any one know a boat electric guru who could figure this out. I'm in Toronto Canada.

[Sailormannn]

Originally Posted by Sailormannn

Here's the news; the problem continues.

New unit arrived on Friday from the factory and was installed today. The installer let it run with the fridge, lights and instruments off charging the batteries and everything looked good. However with the refrigerator on and drawing < 3 amps (showing 10% output on the charger) after about 20 mins or it started flashing high charger temperature warning. I sat beside the charger for the full 20 mins or so and the fan didn't come on once to try to cool the unit. The unit felt warm to touch when it signaled the temperature warning.

I turned the charger off and let the refrigerator run off batteries for 30 mins and the unit was cooling cycling on and off a few times. (draw 3.5A at start up and settles around 2.8A).

I then turned the fridge off and turned the charger on. The fan immediately came on for 10 mins or so. The charge light on the unit was displayed and the remote panel indicated 20% charging output. After 10 mins or so the unit settled back into float stage. The fan stopped and unit indicated <5% output.

I'm at a total loss to explain what's wrong. It must be related to the refrigerator circuit somehow. Any one know a boat electric guru who could figure this out. I'm in Toronto Canada.

H'mm. With no DC load other than my batteries on float and nav instruments that draw very little, the unit just presented an charger overheat warning. The only other thing I had on was my laptop and running my DELL 65w AC power supply plugged into the boats 110v AC. The Xantrex charger was flashing the charger overheat and was hot.

Could this be a problem on the AC side afterall?

[DeepFrz]

Wow, that is really strange.

I guess the only other thing I could suggest is make sure all the wiring for charger remote and fridge are separated. Perhaps ferrite cores on the fridge and charger remote cables. Good luck.

Just saw your second post and to tell you the truth I am really stumped. Not being there and seeing your system it is impossible for me to say anything other than just a thorough going over all your wiring connections may show something. An infrared thermometer scanning the wiring connections might show up something.

If not, it might be time to give up on Xantrex.

[btrayfors]

Actually, it's very simple:

D U M P T H E X A N T R E X !

You've already spent WAY more than the cost of a new charger just diddling with this thing.

Suggest an Iota.

Bill

[Captain Bill]

The thing that your laptop and fridge probably have in common is that they probably are both modern high speed switching power supplies. Though I can't see how the laptop running on the AC side and the fridge running on the DC side would produce the same result. Because of the high frequency switching both could produce some high frequency harmonics that might be incompatible with the new design from Xantrex. It just makes no sense that the AC side would have the same effect as the DC side. On the DC side it might make some sense if the fan control is actually related to the output of the unit rather than the temperature. If the circuit measuring output was "sampling" during a point when the fridge was drawing no power it might be fooled into not starting the fan. I once had a problem using a photodiode to sense if florescent lights were on. These lights are in fact off for 300 microseconds every power cycle. If the computer looked at the photodiode at during that 300 microseconds it would determine that the lights were off when they were in fact on. If the output monitoring circuitry did a similar thing with the amperage output it could be fooled into thinking the output was much lower than in actuality. I would think that the fan circuit would be controlled by the actual temperature but engineers these days like to do lots with software that used to be done with hardware. It would seem to me that if you don't have any thing wrong with your wiring and you've tried multiple units then the problem is in the design.

Have you determined yet if the fan on the new unit is blowing in the proper direction?

[senormechanico]

If your battery is 'squishy' it might be allowing enough of an AC component (generated by the refrigerator electronics) on the 12 volt lines to be backfed to the charger.
This could fool the charger brains into thinking there's an overload.
It could possibly be fooling the fan circuit as well.
Weirder things have happened.

Substitute a new battery or at least another known good one.
I'd not be a bit surprised if it took care of the problem.

By the time I wrote this post, Bill had posted the above.
His post is theorizing on the same type of scenario.

[DeepFrz]

squishy battery?
If there is some AC component being transmitted back on the DC output of the charger that is affecting the charger, then the electronics in the charger are just way to sensitive to be of any reliable use. I'm afraid Bill is right. Time to move on.