Compressor Fridge.

Whenarewethere · Guru

RE: Compressor Fridge.

Bass · Senior Member

WELL... My humblist apologies one and all, after waiting forever in jaycar shepparton I got the clamp meter from total tools got home then started.
Batteries totally disconnected from every thing and each other, then reconnected 2000w inverter.

Battery A 260ahr each Battery B 13.4v Hair Drier connected 13.4v 51.5 amps 12.32v 5mins 12.28v Hair drier disconnected 5mins later 12.97v Fridge connected 12.9v 6.7amp - 7.8amp. 10.47v 15 minutes later 10.47v 100 ahr deepcycle spare battery Fridge connected 12.4v 5mins 6.6amps 12.21v 10mins 7.06amps 12.24v 15mins 6.83amps 12.28v 20mins 6.7amps 12.29v 25mins 6.3amps 12.3v I know it is not a long test but it is enough to let me know that batteries are at fault. if it stops raining I will connect up the thumper to the 12v side of fridge direct and see what happens. It does seem that the batteries are not what they appear. So monday morning back to the battery bloke to tell him testing system is wrong, and of course batteries are 16 months old. now which way do i go and can the enerdrive charge lithium and can the xantrek solar controller do same ?

-- Edited by Bass on Friday 1st of October 2021 04:49:58 PM

Bass · Senior Member

Dam that came out wrong... wash up was that after 15mins through the inverter both batteries down to 10.47volts individually tested. spare 100ahr battery I had in shed started at 12.4 volts when fridge connected through inverter. after 25mins battery voltage was 12.30v.

Whenarewethere · Guru

Could be worse:

Chuck out compressor fridge.

Buy 3 way fridge.

Buy gas every month.

Buy new batteries.

oldbloke · Guru

I am waiting with baited breath

iana · Guru

OK suppose you get this fridge, battery thing sorted, what sort of camping do you envisage doing. If you are mainly going to camps and connected to 240 and occasional one night free camping. or do you see your self doing off the grid camping mainly, two different scenarios.

peatop · Senior Member

I'm happy to hear it's somewhat sorted smile As for your questions on you existing equipment being able to work with LFP (lifepo4) this depends on the make and models. as also stated you need to first weight up the total cost involved to the amount of use, as the outlay you could be up for might make it nonviable, but again this also depends on the ability to use existing equipment.

I started my setup with AGM and before I even used my camper I decided AGM was not suitable to my application and changed to LFP, I will still use the AGM but only as backup.

If your not technically minded or you just buy drop in replacements then buy good quality from a reputable dealer, not doing so could cause major issues with backup service.

2 100Ah LFP batteries will get you going just a bit short of your current capacity but 3 would be more than your current capacity.

Without knowing you current equipment, if you can modify the setting to Lithium or even better adjust the charge voltage to 14.2-14.6 depending on how you want your batteries to cycle and set discharge parameters to somewhere around 10.5v then all should be ok, the internal BMS of the battery should be capable of protecting for over charge and discharge, your 240v charger most likely wont charge LFP and if you have a dc to dc charger that's an older model it may not either, the solar controller may because Lfp has been used in the solar industry for a long time. look at the literature for each unit and it will/should tell you if it is capable of working on lithium. Just as a suggestion I buy bluetooth controlled equipment for my setup only for the reason that it give better/easier access to making changes.

Bass · Senior Member

Thanks guys I still have to do what oldbloke suggested wire an external battery into the fridge and see what happens but at the moment it seems i have bloody big cranking batteries NOT deep cycle batteries. hard wired the inverter to an old 12v deep cycle and plugged the fridge into that after 30 min it was still good having started at 12.4v the BIG batteries were 10.47v after only 15minutes.
We normally do free / bush camping
Dont know yet as have not read the doc's but have an enerdrive system and a xantrek solar controller and think both are lithium compatable. Just heard I have a full 7days to read doc's locked down again. woopee.
So sick of this ****, couldn't go anywhere because of cancer and chemo, then can't go anywhere because we're locked down, then can't go anywhere cause of caravan. Was given maybe 24months in november 2019 my positivety tank is running low.

Aus-Kiwi · Guru

Cheer up champ !

oldbloke · Guru

Im very sorry to hear that. Hope this all works out for the best.

Bass · Senior Member

This is doing me serious brain damage...... Before I started looking at lithium batteries I thought I would redo yesterdays tests. as oldbloke suggested i hooked uo a battery direct to the 12v at back of fridge, NO problem there 12.4v dropped to 12.3v and held. OK inside van remove one battery and place on floor connect up to fridge wire at terminal, NO problem there 12.9v dropped to 12.83v and held. Golly gee and darn ( or words to that effect ) OK connect up the inverter to battery on floor and plugged in fridge ( 240v ) Inverter draining battery at 6.05amps voltage dropped to 12.75v and held ( golly gee again ) stuff it, coffee and lunch. 2 hours later fridge still going and voltage 12.69v. The test yesterday took 15 minutes to drop voltage to 10.47v. THE ONLY DIFFERENCE this time is battery is on floor NOT beside other battery under the bed.
OK place battery back insitu and connect every thing up again, fridge turned on. Now on my way to sons to get his pump action and god help the system if it plays up again. lol.

oldbloke · Guru

Good your getting there.

Sooo, my thought is,
Fridge is ok. Bloody great.

That battery is ok. However other batteries unsure, but likely ok. Perhaps test other battery same way on floor in front of fridge?

Probable fault is somewhere in the other wiring/circuit.

Edit. My understanding is that higher draw items like fridges are usually wired direct to battery. Is yours?

-- Edited by oldbloke on Saturday 2nd of October 2021 07:11:09 PM

peatop · Senior Member

Bass wrote:
This is doing me serious brain damage...... Before I started looking at lithium batteries I thought I would redo yesterdays tests. as oldbloke suggested i hooked uo a battery direct to the 12v at back of fridge, NO problem there 12.4v dropped to 12.3v and held. OK inside van remove one battery and place on floor connect up to fridge wire at terminal, NO problem there 12.9v dropped to 12.83v and held. Golly gee and darn ( or words to that effect ) OK connect up the inverter to battery on floor and plugged in fridge ( 240v ) Inverter draining battery at 6.05amps voltage dropped to 12.75v and held ( golly gee again ) stuff it, coffee and lunch. 2 hours later fridge still going and voltage 12.69v. The test yesterday took 15 minutes to drop voltage to 10.47v. THE ONLY DIFFERENCE this time is battery is on floor NOT beside other battery under the bed.
OK place battery back insitu and connect every thing up again, fridge turned on. Now on my way to sons to get his pump action and god help the system if it plays up again. lol.

Bass, I'm having trouble understanding what your explaining here, I can follow the first part but then when you mention "yesterday" im instantly lost. are you back tracking the story or do you still have a fault?

I am sorry to hear about you troubles, but hey keep your chin up and hopefully we can get your battery situation sorted hmm

Bass · Senior Member

Hi peatop, sorry I would make a terrible teacher. I decided to recheck the system other day "yesterday " I had both batteries electrically isolated from everything and each other then connected the inverter up to Battery A plugged fridge in and 15 mins later battery voltage down to 10,4v dissconnected and reconnected to battery B same story 15mins later down to 10v. This time I removed battery A so i could connect it up to fridge wire at the fuse point. then just because i could i connected the inverter up and plugged fridge in, 2hours later all still good. like i said the only difference between the two tests was that battery A was out beside oven.
OK this is where i am at.... I have 3 faults..... and the fridge comes OUT. I have cranking batteries NOT deep cycle batteries, (lot of time yesterday jotting things down and scratching head) Fridge starts when freezer -16degs, fridge starts when freezer -2degs, fridge starts when freezer -7degs, fridge stops when freezer gets to -10degs, fridge stops when freezer gets to -22degs, fridge stops when well it just bloody didnt. Fridge part of fridge freezer is basicly ok. I installed tempt gauges on fridge and freezer that i could read externally. Now during the tests i didn't open the door yep that's right the freezer looses tempt that quick. because of latch position was hard to do the paper test so I gets a steel ruler and guess what 1/8" to 3/16'' bow in the freezer door.
Why did the fridge drain the batteries so quick 1 day and not the other.
Why did the batteries drain so quick.
Why does the start stop tempts vary so much.
With nothing else connected batteries at 13.1v at 5.30pm fridge on middle setting, by 6.30am batteries 11.6v fridge on but not working freezer -0.6deg and fridge 11degs.
Bow in freezer door.
sorry for long winded reply. upside is had oncology today and are holding the cancer at bay might get another 2 years maybe.

-- Edited by Bass on Tuesday 5th of October 2021 09:05:16 AM

oldbloke · Guru

That is sh1t. Just a thought.....

Did you look ar freezer door hinges.
Possible to adjust or pack...

Or if not adjustable just "bend" it by packing out one spot and push in another....with care.

P.S. great test result. :)

peatop · Senior Member

The number one thing to remember when fault finding is only do one thing at a time (one change at a time) or you may never find the issue, let just focus on one battery or we will have to scroll up and down this thread just to be confused.

1. Lets start with your 240Ah batteries, mark each one "A" and "B" do this, now from what I remember you tested each battery individually to find they are both stuffed?

2. you then connected an external battery "C" and ran your fridge via your inverter, starting voltage 12.4v and after 25 minutes was 12.3v, did the fridge get to operating temp in this 25 mins? and did you measure the current draw of the battery while testing?

3. does your battery system have a power management system (a meter that counts how many Amp hours and/or Watt hours are used)

inline watt meter.jpg this is an inline power meter that can be hard wired to the output of the battery or used to plug in wherever needed.

power meter.jpg This one is a little more complicated and has a shunt, but also has more functions, both these are cheap however all those higher end companies produce one like this shunt one, renogy, victron and others sell for $150+ while these 2 cheaper ones about $25 on ebay.

anyway the plug in one has Wh measurement which counts how many Watts are used over a given period also A,W and V. if your system already has one then you need to use it when running tests, if it has Ah instead of Wh that's ok you just A x V = W although neither of these are needed they sure make track down faults easier.

4. your external battery is a deep cycle 100Ah, fully charge it and run your fridge directly from the battery for 24 hrs, check your starting voltage and ending voltage, if you have a power management system check the starting Wh/Ah and ending Wh/Ah, post you information here. then we can decide what to do next. wink

Bass · Senior Member

Hi peatop, have edited last post a bit. Battery C was only 12.4 v because I got it from under my bench and wasn't charged and only tried it for 35 minutes as it proved a point in that Battery C held up better than either Of the 2 big batteries. Current draw was between 6.7amp - 7.8amp.
Some stats, everything connected up and fridge on 12v.
5pm..freezer..-18, fridge..+2.1...amps 0.0...volts..13v
6.30pm.. freezer..-7 fridge..+6.1..amps 0.7...volts..13v
7pm..freezer-16, fridge..+5.7...amps..5.4...volts..12.4
8.30pm..freezer..-17, fridge..+4, ...amps..0.7, volts..12.9v
9.30pm..freezer..-12, fridge..+6.4,...amps3.5,..Volts..12.5v.
6am.. freezer +0.6, fridge..+12, red light flashing, amps..0.7, volts..10.9v
First part of test was with solar working.
Quick test with Battery C
1.30pm...+0.4...+12.3...7.0amp...12.9v
2pm.......-12.1...+10.6...5.1amp...12.4v
2.30pm...-16.4...+7.7....4.3amp...12.4v
3pm......-17.3....+6.1.....4.7amp...12.3v
3.30pm..-18.4...+5.2......4.5amp...12.2v
The fridge should not drain the batteries overnight (givern the night was 3 degs) and even if fridge ran continesly all night it only needs 216Ahr battery. At the moment not much I can do as DAN has me locked down.

oldbloke · Guru

Let me declare Im no expert. LOL

Soo, to help make it easier to understand I tapped the numbers into a spread sheet. Hope I got them right? The first test indicated the freezer is -7 deg at 1830. Is that a typo Bass?

looks to me batt C is doing OK but 2 hrs is a short test. Both fridge and freezer seem to be operating OK. ---------

EDIT: Yeh, I see, you should get 3 days (up to 80 hours) from 2x240 batts. Flat in 11 hours. No Good.

fridge test.JPG

-- Edited by oldbloke on Tuesday 5th of October 2021 01:24:45 PM

Bass · Senior Member

Nar mate not a typo. Solar probably cut out at about 18.30 those were the figures when i went out to check. Batt C was plugged in at fuse point, no solar. The fridge seems to be not drawing enough to drain both batteries down to switch off so whats draining power nil else on. Yesterday after oncologist fired fridge up and got it to temp then turned it off.
15.30 -18.4.......+5.2
1600 -9.8........+6.1
16.15 -7.7........+6.9
1700 -3.5........+8.1
Have a spare house hold fridge although its not an inverter type might tomorrow morning plug that in via the inverter and see what happens over 24hrs.
Cannot bloody go anywhere anyway so this is just filling in my days. rather be detecting though.lol

iana · Guru

Does your fridge run on 240 volts, i.e. separate from the 12volt system. For instance is there a 240v lead there for it?
Its interesting that I am about the only person on this thread with the same make / type of fridge, having gone through similar problems, I find the thread a bit frustrating.

peatop · Senior Member

Ok again the number one thing is only test one thing at a time hmm If you have a charging source connected the test fails, especially given that you don't know it's input amount,

to start any test you need to disconnect everything and only have the batteries connected to the fridge and a fuse if needed (and if you have a measuring device/s them too).

Once we know the state of you power source, then we can move on from there to rule out the next possible cause, but if your test is void then we cover no ground.

That first meter I posted comes in multiple connection configurations and if you connect one up to the output of the battery and input of the fridge this will tell you the total power consumed over the test period.

Lead acid batteries have a 20 hour discharge to get the most out of them, what this means is if you have a 100Ah battery you can only take 5amps an hour avg from that battery to get 100Ah from it, also drawing more than 5 amps an hour will drop the voltage proportionally to the over recommended discharge rate, this discharge is over 20 hours so you can draw 6, 7 or more amps for intermittent periods without causing issues (example a fridge starting and stopping every 10 or so minutes).

When I tested my fridge, I installed a power meter to get the avg draw over 24 hours this was important to me to get a semi accurate figure as to what my fridge need to run it while free camping, I also checked voltage at the beginning and end of the test to get and idea of voltage drop and state of the battery at the end of 24 hours. so the use of a power meter told me under test conditions the fridge use XX.XX watts/amps over the 24 hour period it was tested, the reason we fit power meters gives us a quick view at what's going on with the system at a glance and it's also very useful in tracking down faults.

Now I'm not sure if your 240Ah batteries are at fault, just because I don't know how you tested them. slow and steady is how you will track this down.

oldbloke · Guru

I think we need to clarify what his batteries are. I'm confused. 2x240 AH batts got mentioned at one point. I didn't know they existed.

Bass can I ask what Batts are in the van and how many?? Type & AH?

Bass · Senior Member

Iana, I have 240v to one end of PC Board and 12v to the other. I have 240v to compressor controller and 12v to compressor controller. somewhere in the controller it steps up / down to 24v as that is what the compressor is.
I have 2 x 260Ahr batteries believe they are CCA not deep cycle.
I have connected up everything as normal by morning the fridge is on BUT not running and red light flashing battery voltage normally below 11v.
I have disconnected every thing except circut required for fridge, by morning fridge on but not running and red light flashing voltage normally below 11v
I have disconnected everything and electrically separated both batteries, connected up Inverter to battery A plugged fridge in turned on, in 15 minutes battery voltage 10.7 volts
Connected Inverter up to battery B plugged fridge in turned on, in 15 minutes battery voltage 10.47 volts.
Removed battery A and placed beside oven connected inverter plugged fridge in turned on 2 hours later still all good.????
The fridge should not , (even if running at full tilt 9amps and 65watts continually for 12hours) drain the batteries overnight. (216Ahr battery should be ok.)
I am now waiting for fridge to get to tempt and have the 5year old 100Ahr deep cycle battery ready and will connect it to fridge 12v fuse point and let it go till it cannot go anymore.
Something is draining the batteries. and before you ask with everything off no amps are going through system and with only fridge on, only fridge amps are indicated.
Because of lock down cannot take it to auto elect. keeping me occupied. lol

Whenarewethere · Guru

Your 2 x 260AH maybe starter batteries but they will still work okas long as they are not stuffed.

I use my 2013 80AH Exide starter battery for all sorts of testing. It's still basically ok in 2021, 4 years out of the car.

I have even connected current starter battery, old one & 4 gel batteries for a test with a "large" 269AH setup.

I have run my fridge for days off the old 80AH starter battery for other tests.

Test your batteries with a nominal load similar to the fridge, a halogen down light or 2 will work, & document the data.

oldbloke · Guru

I have 2 x 260Ahr batteries believe they are CCA not deep cycle
216Ahr battery should be ok.

what is it?

I'm confused

Whenarewethere · Guru

Whether it is 2 x 260AH or a single 100AH battery. The fridge is consuming 6.3amps when the compressor is running. Either will cope with 6.3amps, one setup will last longer.

iana · Guru

Our fridge is the RPD-215, obviously a different design. Draws 6.5 amps. One single 12/24v connection. I will but out.

rgren2 · Guru

Im confused too, is the fridge running on 240v through an inverter?

Bass · Senior Member

I have 2x260 ahr batteries which the fridge drains to cut off point of 10.5volts at some time during the night, now wether they are cranking or deep cycle they should still cope. even at max current draw for 12 hours a battery of 216ahr would cope. both my batteries were new in march 2020.
Because the fridge drained the batteries on 12v I pluged the fridge into the inverter just to test it. I do not care how much power is used when I'm in a caravan park, the fridge can run all night if it wants.
When free camping something is draining the power when I switch the fridge on, because at maxium draw of 65 watts ( according to manual ) it cannot drain the batteries to cut off overnight.
So I tested each battery in turn on both 12volt and with the Inverter and by themselves and with all circuts connected in turn, and also with a 100ahr deep cycle battery that was lying about in shed. Every time same result batteries draining faster than should. every time the only amp draw on system is fridge amp draw ( as measured by clamp meter ) you guys can work it out.
2 x260 Ahr batteries. current draw of fridge 6amps (ave) 65watts and starting voltage of 13.0volts... Now given no charging of both batteries how long should they last till they reach 10.5volts.
As I type the 100Ahr deepcycle battery is hard wired direct to fridge. starting voltage 12.9volts almost 5 hours later voltage is 12.47v.
God i wish i had a 3 way fridge, and sorry i started the subject.
Goodnite

yobarr · Guru

Bass wrote:
I have 2x260 ahr batteries which the fridge drains to cut off point of 10.5volts at some time during the night, now wether they are cranking or deep cycle they should still cope. even at max current draw for 12 hours a battery of 216ahr would cope. both my batteries were new in march 2020.
Because the fridge drained the batteries on 12v I pluged the fridge into the inverter just to test it. I do not care how much power is used when I'm in a caravan park, the fridge can run all night if it wants.
When free camping something is draining the power when I switch the fridge on, because at maxium draw of 65 watts ( according to manual ) it cannot drain the batteries to cut off overnight.
So I tested each battery in turn on both 12volt and with the Inverter and by themselves and with all circuts connected in turn, and also with a 100ahr deep cycle battery that was lying about in shed. Every time same result batteries draining faster than should. every time the only amp draw on system is fridge amp draw ( as measured by clamp meter ) you guys can work it out.
2 x260 Ahr batteries. current draw of fridge 6amps (ave) 65watts and starting voltage of 13.0volts... Now given no charging of both batteries how long should they last till they reach 10.5volts.
As I type the 100Ahr deepcycle battery is hard wired direct to fridge. starting voltage 12.9volts almost 5 hours later voltage is 12.47v.
God i wish i had a 3 way fridge, and sorry i started the subject.
Goodnite

Trust me,you will not "Wish I had a 3 way fridge if you ever do get one.They're ancient technology,and effectively useless.Don't do it! Cheers.