Fusebox fan is cycling on and off

[5thhorseman]

Hi all, I'm very new to the RV world and have only done one trip which unfortunately ended up with my fridge failing (due to rough FSR), but that is now fixed and documented in this thread.

Since then (last 2+ weeks) I've been running the fridge and testing the thermostat on various settings to record the resultant temperature in the fridge and freezer to get a sense of the optimum setting. I was running off the battery (lithium + solar) which was fine until the other day when I found no power at all! (I had not been monitoring the battery level ... as I said, I'm a noob).

So I plugged into shore power. EMS showed 4 (previous error, low battery) and the Go Power panel showed 13%. So why did the battery drain? I was using power for the following:

1. Norcold fridge (2A draw, average)
2. Heating pads on
3. Inverter on (to run Inkbird for monitoring fridge temp)
4. One interior light on

So first, yes I know the heating pads shouldn't have been on. They're for extreme cold and not a winterisation technique, as I've since learned. But my understanding is that they are thermostatically controlled, so they shouldn't have caused the battery drain.

My guess is it was a combination of a change to very cloudy/rainy weather here plus the inverter draw, which caused the problem? Sound right? I assume most people only turn on their inverter for short periods of time when boondocking.

Now my main question, with everything off and connected to shore power, the fan at the bottom of the fuse box keeps cycling on every 2min 15sec for about 5-6 sec. That was at 13% battery. I checked again this morning and the battery is back to 100% but the fan still cycles, going on and off twice in 5-6 seconds now!? Once I disconnected shore power there is no more cycling.

I searched the forums and didn't find anything similar. Anyone have an idea?

[7Gentex]

So you had all that on while not hooked up to shore power for 2 weeks..........?

Do you have solar panels? Was unit in the sun?

How many / what spec batteries do you have?

Per this post, that refridge draws about 30-35 amp hours per 24 hours. So, ignoring solar, maybe 3 days tops per 100 amp/hour battery?

https://www.escapeforum.org/forums/f...tml#post424995

[Vermilye]

A couple of things that might help figuring out what is going on.

First, the EMS only shows 120V problems - it is not connected to the batteries. A code 4 (low voltage) indicates that the input voltage to the trailer dipped below 106 volts.

The fan in the converter is powered by 120 volt shore power, ie if you disconnect ie shore power, the fan won't run. It runs when the converter draws enough power to heat enough to need additional cooling. That is likely to occur when the batteries are low and draw lots of current.

The high temperature cut off for the heating pads is usually well above freezing - they may have been drawing battery current.

The GoPower inverter draws at least an amp even without a load. It would be better to use a battery powered temperature monitor to keep an eye on the refrigerator. I used either this one to monitor just the refrigerator or this one to add the outside temperature. A more expensive but useful since it can be monitored on a smart phone is the Sensor Push device. You need one for each thing you wish to monitor. Another advantage is it keeps a daily/weekly/monthly log of the temperatures.

[Selkirk]

I would also speculate that the tank heating pads could a be contributing factor to the low battery. The pads are indeed thermostatically controlled, but believe they are set turn on at about 5deg C and draw in the neighborhood of 10A continually each when active. It would only take only one or two cool evenings during the 2 week period to substantially drain even 200ah worth of lithium batteries.

Combine that with the constant load from the fridge/inverter/light, and my guess is that the solar simply couldn't keep up with the overall power demand in the poor weather.

[5thhorseman]

Originally Posted by 7Gentex

So you had all that on while not hooked up to shore power for 2 weeks..........?

Do you have solar panels? Was unit in the sun?

How many / what spec batteries do you have?

Per this post, that refridge draws about 30-35 amp hours per 24 hours. So, ignoring solar, maybe 3 days tops per 100 amp/hour battery?

https://www.escapeforum.org/forums/f...tml#post424995

Yes, that was disconnected from shore power since April 13th at least. Mostly sunny for the first week and then mostly cloudy/rain since then.

I have two LI batteries, 100Ah each. Two 190W solar panels.

[5thhorseman]

Thanks for all the responses. Between the cloudy weather, inverter, and heating pads, it seems there was plenty to drain the battery. Case closed. I'm now going to just run the fridge + a few lights/fans on solar to get a feel of how well it can keep up during cloudy periods, starting with a full battery.

How do I keep tabs on the Ah left in the LI batteries? Do I just go by the % on the GoPower panel? I noticed the kAh reading hardly changed from when the battery was low (13%, 7.47 kAh) to fully charged (100%, 7.51 kAh). This doesn't make sense to me.

Originally Posted by Vermilye

A couple of things that might help figuring out what is going on.
First, the EMS only shows 120V problems - it is not connected to the batteries. A code 4 (low voltage) indicates that the input voltage to the trailer dipped below 106 volts.

I'm parked out at the back of the property. I have 150' of underground cable to a GFCI in my chicken coop, then 50' of extension cord to a second coop with broilers, then another 50' to the HD cable that came with the Escape. Not ideal but the best I can do without parking in the driveway (don't want that) and another reason I want to run only on solar when parked. Not surprised that it dropped below 106V. Case closed on the EMS code PE 4 then.

Originally Posted by Vermilye

The fan in the converter is powered by 120 volt shore power, ie if you disconnect ie shore power, the fan won't run. It runs when the converter draws enough power to heat enough to need additional cooling. That is likely to occur when the batteries are low and draw lots of current.

This is the outstanding issue as it cycles on/off every 2m16s, whether the batteries are low or fully charged.

Interestingly, this is exactly the same as the delay for the EMS to reset. So maybe something to do with low shore power voltage? I could test that theory out if I park closer to the house.

[5thhorseman]

Originally Posted by Vermilye

The GoPower inverter draws at least an amp even without a load. It would be better to use a battery powered temperature monitor to keep an eye on the refrigerator. I used either this one to monitor just the refrigerator or this one to add the outside temperature. A more expensive but useful since it can be monitored on a smart phone is the Sensor Push device. You need one for each thing you wish to monitor. Another advantage is it keeps a daily/weekly/monthly log of the temperatures.

Thank you! I think I am done with the Inkbird now and have turned off the inverter. The ideal setting for the fridge seems to be about 1.5 but it would be handy to have a log of the temperature so I may yet use this info. I did find the fridge's thermostat to be finicky (as with most fridges), so if I find further issues I will consider permanently installing a 12V Inkbird to control the fridge temp.