Fridge Causes Voltage Drop?

[0976claxton]

Just experienced a similar situation last weekend while in the White Mountains. Voltage (as measured on my Morningstar PM 15) dropped rapidly from 12.6 volts to 11.x within one hours, causing the low voltage alarm on my propane sensor to go bonkers just as the toddler and wife fell asleep. Ended up shutting down everything, and replacing my batteries the next day in Bishop. The original batteries were only 2.5 years old, but were some cheap sealed acid batteries from BatteryPlus. I didn't bother to have them stress tested before replacing. I assumed they were the issue and just ended up replacing them with two bluetop Optimas . It was a bit of a knee jerk reaction. Spend more money, and the problem should go away, right? What I'm curious about is the bulk load comment. My controller previously showed over 14 amps going to my batteries in good sunny conditions (180w grape solar on top). Am I safe to say that this is an overcharging issue? Shouldn't the controller hold the charge at 12.6 or so?

As for the fan, I'll search this forum some more for the information, but while I'm at it here: what fan are you guys going with? Seems like some good circulation in the fridge would help with efficiency at some scale. Last weekend was extremely hot outside, so I'm not sure it would have helped in this case as the fridge was working overtime to keep my beer cold.

 

[Desert Scruff]

A Valtera Fridge Cool Fan is what I got and a couple of tests I've run shows it's keeping the fridge shelves the same temperature. There are others here who have more experience with the fan than I. It's cheaply made and Amazon says it's unavailable. There is a second Valtera fan that gets a little better reviews.

 

[rando]

14 Volts or 14 Amps going into your battery with full sun? Either would be OK during bulk charge, but 14V is too high for a float charge voltage and could explain your short life.

Just experienced a similar situation last weekend while in the White Mountains. Voltage (as measured on my Morningstar PM 15) dropped rapidly from 12.6 volts to 11.x within one hours, causing the low voltage alarm on my propane sensor to go bonkers just as the toddler and wife fell asleep. Ended up shutting down everything, and replacing my batteries the next day in Bishop. The original batteries were only 2.5 years old, but were some cheap sealed acid batteries from BatteryPlus. I didn't bother to have them stress tested before replacing. I assumed they were the issue and just ended up replacing them with two bluetop Optimas . It was a bit of a knee jerk reaction. Spend more money, and the problem should go away, right? What I'm curious about is the bulk load comment. My controller previously showed over 14 amps going to my batteries in good sunny conditions (180w grape solar on top). Am I safe to say that this is an overcharging issue? Shouldn't the controller hold the charge at 12.6 or so?

As for the fan, I'll search this forum some more for the information, but while I'm at it here: what fan are you guys going with? Seems like some good circulation in the fridge would help with efficiency at some scale. Last weekend was extremely hot outside, so I'm not sure it would have helped in this case as the fridge was working overtime to keep my beer cold.

 

[ardvark]

Suggest checking charge controller voltage with a meter. Maybe it is the problem, but maybe not.

 

[Vic Harder]

ditto to what rando said during bulk mode you can do LOTS of amps during float you want a very specific voltage per the specs for your new blue tops that is 13.2 to 13.8 volts

 

[0976claxton]

yes. sorry guys, 14 volts. thanks for the catch. Not sure how long the bulk charge was on the old batteries though. Going forward, i'll test the controller voltage with a multimeter and keep an eye out for the 13.2 to 13.8v charging.

 

[dharte]

Does anyone know a better alternative to the Zamp that will mount in the same opening? I'm convinced my batteries are being overcharged-I can hear them gurgling and my propane/CO detector continues to randomly go off in the middle of the day when the panel is getting the most sun.

 

[rando]

That sure sounds like it is boiling your batteries.

The Victron offerings are a much better option - but are a completely different form factor. The only other reputable option I am aware of that is a similar form factor (but likely different dimensions) are from bluesky: http://www.blueskyenergyinc.com/

I wonder if you could make a trim panel to fill the Zamp hole then mount the Victron gauges in the trim panel.

 

[dharte]

That sure sounds like it is boiling your batteries.

The Victron offerings are a much better option - but are a completely different form factor. The only other reputable option I am aware of that is a similar form factor (but likely different dimensions) are from bluesky: http://www.blueskyenergyinc.com/

I wonder if you could make a trim panel to fill the Zamp hole then mount the Victron gauges in the trim panel.

I could easily make a trim panel, but I was looking on-line at the Victron, and it appears the wires attach to the front of the panel-this would be a real eyesore inside the camper.

 

[Vic Harder]

hide the controller wherever and put the companion guages out where you can see them

 

[dharte]

I just ordered the Blue Sky SB3000i. It's flush mount and fully programmable to set the exact voltages for absorption and float charging.

 

[Wallowa]

seems to be overcharging them.

VIc,

Let me re-visit the possibility of the FWC batteries being over-charged. With the FWC Q4 contoller and plugged into an external 110v source what voltage should the OEM FWC status screen display? Mine shows a steady 13.6 v. I store my '16 Hawk in my shop with external power plugged in.

Not saying that there is not a potential issue but honestly how many stock/OEM FWC systems cause battery failure or premature draw down? Is it indeed a highly probable weakness or is this an infrequent issue?

I appreciate all the thought and expertise that has been demonstrated on the possible problems with the FWC charging/battery system as delivered. But is a battery related issue that prevalent?

For the lay person, me, deducing if my electrical systems need upgrading has been very confusing and just replacing a plethora of components that may or may not be needed just further muddies the water for me.

Anyway thanks to all for this discussion. Just wish there was a more definitive "cookbook" of how to diagnose any impending issues and then the steps to alleviate them.

Phil

'16 Hawk
w/full FWC Zamp solar roof and portable panels

 

[PaulT]

Phil,

Not Vic here, but I have similar to your set up. Zamp controller, and Iota with IQ4. 13.5v or 13.6v is float voltage for the AGM batteries. After batteries are fully charged, I see 13.5 or 13.6 indicated on the Zamp display with either full sun on the solar panels or with the camper plugged into shore power.

There will be higher voltages displayed for some time after sun comes up or after plugging into shore power but there will be a return to 13.5 or 13.6 after batteries reach full charge and either charger decides that full charge has happened.

After a week or two on float, both the Zamp and the IQ4 will revert to bulk, then absorption and back to float to ensure that the batteries are kept fully charged.

Paul

 

[smlobx]

I had a similar fast draw down last week while camping in the GWNF.
The thermostat in my fridge was accidentally set to the lowest setting and my solar panels were mostly shaded due to where I parked. Almost everything in the fridge was frozen solid the next morning...
I saw voltage (on my Zamp Controler) as low as 9.7V.

I'm afraid I cooked my 6 volt batteries. Right now I'm trying to revive them with my NOCO charger but it may be a mute point.

 

[Vic Harder]

13.6 is a reasonable float voltage for some batteries what do your specific batteries need? and is this after several days so we can expect that this is the float voltage?

 

[Wallowa]

13.6 is a reasonable float voltage for some batteries what do your specific batteries need? and is this after several days so we can expect that this is the float voltage?

Float charge for certain....seen when plugged into 110 and no real draw sitting in my shop...as to what my specific AGM batteries "need", I have not a clue...OEM FWC dual 12v..

So far never a hick-up with our Hawk...fingers crossed...solar [160 +80] and then when changing locations Tundra alternator ifitis needed.

Phil

 

[PaulT]

See http://www2.exide.com/media/partscatalog/documents/Battery%20Specification%20Sheet%20FP-AGM24DP.pdf

Assuming you have the Exide group 24 Edge AGM marine dual purpose

Float voltage is 13.5v to 13.8v

Paul

 

[Wandering Sagebrush]

See http://www2.exide.com/media/partscatalog/documents/Battery Specification Sheet FP-AGM24DP.pdf
Assuming you have the Exide group 24 Edge AGM marine dual purpose
Float voltage is 13.5v to 13.8v
Paul

Perhaps an aside... I had an interesting conversation with an RV builder about batteries. They bought a somewhat large number of batteries from Exide to put in their new units. I was told that Exide, rather than shipping their in house manufactured AGMs from their East Coast US plant, imports batteries from China for the West Coast, and that they (the builder) had to warranty a very high percentage of the batteries.

 

[RajaZoie]

We were / are having a similar issue where our batteries were going "empty" overnight with just the fridge running. We replaced our 2 1/2 yr old Exides and I just got the Victron BMV 700 battery monitor to see if we have something else going on as well (although it appears we are back to normal with the new batteries). We have a 2015 Hawk which we got in December of 2015 so I wonder if we all got a bad batch of Exide batteries.
Great info up here.

 

[radarcontact]

Apparently I'm having a similar problem, wanted to bounce it off you guys. I have a 2014 Hawk with Zamp controller, 160W panel, 2-way Dometic frig, and 2 12V 85ah Fiamm batteries that came from the factory. I leave the camper parked in my garage, plugged into shore power when I'm not using it. Every time I go camping, the frig will run normally for an hour or so, then it starts cycling on and off. The compressor would start, but only run for 10-15 sec, then click off. I happened to look at my Zamp controller when this was happening, and my voltage would drop, from, say, 12.6V down to below 11V in 10 sec, which would cause the frig compressor to shut off, as it wasn't receiving enough voltage to continue to run. This has been going on for awhile now....when I was camping in California last fall I had a shop test the batteries, and they said they were ok, but I don't think they put a load on them. As it stands right now, the frig is useless for camping on battery power. When I first got the camper in 2014, we camped remotely on some BLM land in Arizona for over a week - never started the truck, and the frig and other electrical stuff ran perpetually, with the charge the solar panel would give it during the day. Besides the frig, we're not really using a lot of juice...just a light, and a ceiling fan at times. I'm going to pull both batteries out of the camper and take them to a shop and have them tested again....any other ideas? If the batteries check out ok, I guess the next thing is to replace the solar controller, from what I'm reading on this thread. If the batteries are bad, maybe I should replace the controller as well....? Overcharging? It's pretty confusing, and frustrating.