Leisure battery

corktina · 10-07-2013 6:05pm

I got the fridge working with mains charger plugged in....voltage was holding it's own and fridge quite cold but then suddenly voltage collapsed to 9v and fridge stopped working . Can only really be a dodgy battery I guess not holding the charge and when the voltage dips below a certain point, I suppose the fridge cuts out. I'll go looking for a cheap battery I think...

10-07-2013 6:50pm

Sound enough theory alright.

It usually takes about 4 hours for a fridge to reach temperature. If 12volt is doing it sufficiently then I think the transformer is the way forwards. Even with a new battery a 7Ah constant load will put the battery under serious pressure and interfere with your mains charger, overcharging your new battery. Not to mention what lights and mod cons. you will need.
You could pop into Aidan and get the gas related side working too as another option.

corktina · 10-07-2013 6:53pm

ah I had forgotten Aidan, I assumed he was a garage...is he a gas fridge expert then?

10-07-2013 7:02pm

Certified gas fridge expert, Pat Horan Motors. You could try PM though.

10-07-2013 7:04pm

Deadly I just got my 3rd star

corktina · 10-07-2013 7:16pm

and just over an hour .voltage back to around 12v...

(PM sent to Aidan

corktina · 10-07-2013 7:16pm

Sir Liamalot wrote: »

Deadly I just got my 3rd star

all due to me!

niloc1951 · 10-07-2013 8:11pm

Hi corktina, don't know where you are but if the clue is in your name give Leonard or Gabriel a shout at O'Connell Bros.. They have a good range of genuine leisure batteries as opposed to the imposters sold by some.

They will give you a definitive verdict on your battery and also probably check your wiring/relays/fuses but I don't expect they will know much about fridges.

10-07-2013 8:23pm

corktina wrote: »

I then went for a 10 mile drive with the fridge on. Leisure battery went down immediately to about 11v, main battery at almost 13v. Checked fridge after 10 miles, warm still, no sign of life. Turned off fridge, leisure battery recovered to about 11.5 or 12v on way home.

Clearly the leisure battery, whilst it may well be weak and old (like me) charged from the mains but was not charging from the alternator, which is most odd.

I don't know how I missed this entire section of evidence earlier. But you figured it out so all good.

If you have two different readings from your two batteries then you know they aren't linked and vice versa. Say Battery #1 is 12.8v and Battery #2 is 12.4v then when you link them they will be 12.6v.

10-07-2013 8:26pm

What do you mean by genuine leisure batteries Niloc? Semi-traction, or branded?
What's an imposter? A starter with leisure written on it?

niloc1951 · 10-07-2013 9:22pm

Sir Liamalot wrote: »

What do you mean by genuine leisure batteries Niloc? Semi-traction, or branded?
What's an imposter? A starter with leisure written on it?

Follow THIS LINK for the answers

10-07-2013 9:57pm

I recently became wary when batteries are branded as leisure or marine. That's really not telling anything other than the markets they are targeting. If I brought a 1.5v AA Duracell for a torch onto a boat that would then be a marine battery.

corktina · 10-07-2013 10:05pm

niloc1951 wrote: »

Hi corktina, don't know where you are but if the clue is in your name give Leonard or Gabriel a shout at O'Connell Bros.. They have a good range of genuine leisure batteries as opposed to the imposters sold by some.

They will give you a definitive verdict on your battery and also probably check your wiring/relays/fuses but I don't expect they will know much about fridges.

grand so, I'll be up there friday, I'll call in Thanks.

corktina · 11-07-2013 12:50pm

left charger on all night...leisure battery reading higher than main battery now

BUT i put my mondeo battery in which i knew to be a little flat as it hadn't been used for ages and it reached 12v+ in no time...

11-07-2013 1:15pm

That's pretty normal. The leisure battery is probably highly sulphated which gives it a very high internal resistance, meaning it takes a long time to charge as the charged ions are finding it difficult to travel through the stratified plates.
Your car battery is probably smaller too.

corktina · 11-07-2013 1:16pm

thats true...did nt think of that :-)

Aidan_M_M · 11-07-2013 4:40pm

Thanks for the recommendation about Gas guys. Not blowing my trumpet but I'm fairly hot on 12v wiring , it's one of my specialties. Corktina, pm replied to, how much of a hurry are you in to get it fixed?

corktina · 11-07-2013 4:51pm

nothing spoiling really, would be nice to have the fridge running on gas though.

corktina · 21-07-2013 8:52pm

OK, next act...went to Trim today, put van on mains charge the night before and fridge on....thought it would be nice and cold, checke din middle of night...battery flat and fridge warm....arrrrgh.

OK thinks I, must be OK when I'm driving so charged up without the fridge on and set off with battery chrged up and fridge back on.....flat agian after half an hour. Surely it should have run the fridge from the ALTERNATOR EVEN WITHA FLAT BATTERY.

niloc1951 · 21-07-2013 9:59pm

corktina wrote: »

OK, next act...went to Trim today, put van on mains charge the night before and fridge on....thought it would be nice and cold, checke din middle of night...battery flat and fridge warm....arrrrgh.

OK thinks I, must be OK when I'm driving so charged up without the fridge on and set off with battery chrged up and fridge back on.....flat agian after half an hour. Surely it should have run the fridge from the ALTERNATOR EVEN WITHA FLAT BATTERY.

Looks like you need to take the van to someone like Aiden-M-M for a hands on look at the problems.

When on mains the fridge should work off that source, it should not be drawing off the leisure battery and the leisure battery should be charging.
When driving the fridge should work off the alternator and the leisure batteries should be charging.

The fact that you appear to have multiple faults would indicate you need to have it looked at by someone who understands the fridge and charging system in motorhomes. It is possible that a single simple fault is the root cause.

21-07-2013 10:19pm

What size in Ah is your battery? Is this a new one or the same as Act 1?
Are you aware that you are boiling all the active material off your battery plates by loading it like that on charge? Pretty soon it'll be a lead acid block with no chemistry left. Have you checked the electrolyte level?
A completely dead battery <100Ah, if it recovers at all can take between 5 to 12 hours to recharge. The voltage reading on your dash with the engine running is the alternator + engine battery assisted voltage, not the true leisure battery voltage.

If it's still the old battery that all sounds perfectly normal for a battery that's had such a hard life.

I don't recommend using 12V to run the fridge at all it'll just destroy your battery. They rarely get down to temperature on 12V it's just a go-between for when gas/electric isn't an option. There are efficient box type, top loading fridges that work on 12V. They prevent the cold escaping when the door is opened.

You've 4 options as I see them.

Get an energy efficient fridge.
Fix the gas on the one you have and just use 12V when moving.
Retrofit the fridge to run from mains on the 12V element with a >7A transformer and just use 12V when moving.
Get 400Ah of batteries to run it and everything else you need for one 24hr day.

corktina · 22-07-2013 3:55am

niloc1951 wrote: »

.

When on mains the fridge should work off that source, it should not be drawing off the leisure battery and the leisure battery should be charging.
When driving the fridge should work off the alternator and the leisure batteries should be charging.

T.

exactly, that's why I have been slow to go get a new battery and destroy that one potentially. Meter read 10 volts all the way home (160 miles) without the fridge turned on , plugged in charger when I got home and meter was on 13v within half an hour. As you say, there is something screwy in the wiring and I'll figure it out yet!
I'm going to transfer my Mondeo battery into it later, plug it in and see what happens. If the fridge works this way I shall prove it's the battery at fault, if it doesn't then elsewhere is where I'll look

gctest50 · 22-07-2013 4:08am

"Half" your battery might be sulphated or otherwise knackered - it'll look ok on a voltmeter and charge up easily ( and discharge easily - basically behave as a tiny 12v battery )

EDTA might work if its sulphation - probably just waste of time and effort though

corktina · 22-07-2013 4:10am

gctest50 wrote: »

"Half" your battery might be sulphated or otherwise knackered - it'll look ok on a voltmeter and charge up easily ( and discharge easily - basically behave as a tiny 12v battery )

EDTA might work if its sulphation - probably just waste of time and effort though

...but then it would charge off the alternator as well as the landline would it not and the fridge should work when plugged in too.

gctest50 · 22-07-2013 4:12am

Yip, you has gremlins in your system just for added fun

When you fix the fault, install an ammeter in the cable to the leisure battery - will give you an instant picture of what is going on

http://www.motorclocks.com/

http://www.compass24.com/product/13187018/nasa-clipper-battery-monitor

http://oconnellbrothers.com/

.

corktina · 22-07-2013 10:47am

so far I have found a blown fuse in the wire which connects the batteries together. van and fridge are running at present, so I shall know if this is the problem or just Part of it. (I think the battery needs replacing but don't want to do this until I can ensure that the new one doesnt get knackered too....fridge should run with engine running and also when on landline...

RECAP

Landline will charge battery but not run fridge...I can't see how this blown fuse affects that
Alternator is now I hope charging battery and running fridge...if not , then why not? There is power at the fridge (fridg is ancient and may just be knackered itself of course but it does work when battery has been charged on landline, for a while until ccharge is lost

Aidan_M_M · 22-07-2013 12:06pm

That fuse won't affect the fridge on 220v. To recheck , the fridge NEVER cools on mains? Sounds like a blown 220v element.

corktina · 22-07-2013 12:09pm

it's not a three way. Running on 12v, should not the charger maintain the leisure battery enough to run the fridge whilst plugged in?

Fridge now running whilst the engine is running but not so far whilst battery is on charger (prob battery is
gone but I want to rule out other faults before replacing it.)

PS fridge isn't getting really cold and is very old so I'm thinking of replacing it altogther

Aidan_M_M · 22-07-2013 12:16pm

Yes, it should. So 12v and gas only? Sher it can't work on 220v then without a transformer.

corktina · 22-07-2013 12:20pm

If the van is hooked up to the mains and the built in charger is charging the Leisure Battery, should not the fridge run, assuming the battery is at 12v or so to start with? I'm going to try my car battery in it's place and see what happens.

Could it be as simple as a duff battery? seems to charge up OK on mains

Aidan_M_M · 22-07-2013 12:40pm

Oh right, so it's still 12v, from the battery. Gotcha.

Aidan_M_M · 22-07-2013 12:41pm

Could be a weak charger.

corktina · 22-07-2013 12:43pm

charger is charging. Got home yesterday with 10v on the meter all the way home, plugged in and over 12v in half an hour. (blown fuse would have been cause of alternator not charging battery on way home imho)

Saw your sign on way to trim, so know where you are now)

MammaZita · 22-07-2013 1:15pm

corktina wrote: »

charger is charging. Got home yesterday with 10v on the meter all the way home, plugged in and over 12v in half an hour. (blown fuse would have been cause of alternator not charging battery on way home imho)

Saw your sign on way to trim, so know where you are now)

Not sure where you're based, but we've regularly brought our motorhome to Maynooth Motorhomes to get things like that checked out. Well worth it for peace of mind to get the experts to have a look so you can enjoy stress free camping.

22-07-2013 1:56pm

Here's a wiring diagram.

Wiring Transformer on Fridge 12V Element .JPG

6 pole switch shown in "mains supply" mode. Switched to the other position it will set to leisure battery mode.

You can wire the AC input direct from the rear of your van your hook up plug point after the main RCD or wire it to a standard plug and designate a socket inside the camper to power it.

I'm keeping it simple here so no more relays just good big switches and cable. Use 1.5mm stranded cable for the lot and you'll be fine.
Make sure the 6 pole switch is DC rated not AC.

If you want to use more relays and can keep the wiring neat I can send you another diagram but I don't really see the need. I'd be open to suggestions how to automate this setup? ...tehehe more, more relays I reckon...haven't thought about it much.

As for fuses you can decide yourself whether you want to use AC or DC appropriate fuses, in my experience unless you want time-delay or fast-blow it makes little difference.

[Edit; take the "fridge switch" on diagram to be D+ off alternator battery light or your chocolate block feed]

22-07-2013 2:18pm

corktina wrote: »

If the van is hooked up to the mains and the built in charger is charging the Leisure Battery, should not the fridge run, assuming the battery is at 12v or so to start with? I'm going to try my car battery in it's place and see what happens.

You're not allowing the battery to complete charge. The batteries won't charge more than 80% when you put a 7A load on them. You're therefore suspending the battery in Bulk Charge for inordinate amounts of time. Causing boiling of electrolyte, stripping of the active material of the battery plates and releasing fistfuls hydrogen, your electrolyte has possible evaporated away exposing the plates causing further sulphation and the plates that are probably warping from the heat and will soon start shorting.
Also because it has been deeply discharged so often the sulphates from the sulphuric acid in the electrolyte have fallen out of solution and bonded to the plates as a hard limey substance (for want of a better PH related word) considerably reducing conductivity and increasing internal resistance.

You are correct though the scenario you describe will work on a good battery but it's inadvisable for the reasons I've said.

There's a possibility your battery is so banjaxed now it won't take or hold charge so the alternator/mains charger is giving it all it can and it's just being lost in the depths of lack of charge acceptance.

corktina wrote: »

Could it be as simple as a duff battery? seems to charge up OK on mains

There's a potential wiring problem between your batteries as the fuse has gone twice now.
It could also be the amperage rise due to voltage drop, or a bad specification. What size is the fuse? What thickness is the wiring? What is the output of your alternator in Ah (check service manual)?

niloc1951 · 22-07-2013 2:43pm

To go back to square one, corktina.

Leisure battery charges when on mains.
Leisure battery goes flat when engine running.

The typical reason for this is a broken connection, or blown fuse, between the engine battery and the leisure battery system.

This is what happens in those circumstances.

Engine starts, alternator starts producing power, relays for fridge and leisure battery close to allow charge to run from the engine battery to the fridge (so it can run on 12v) and the leisure battery (so it will get charged).
However, because of the break in the circuit from the engine battery no power is arriving to either.
But, because both relays have made (closed) and there is a common wire to the engine battery which is not connected to the engine battery (broken connection , blown fuse) the power will flow from the leisure battery direct to the fridge, result flat leisure battery and fridge no longer working.

Note: the fridge is never supposed to run from the leisure battery unless the engine is running (alternator producing power). when on mains hook-up it should run on mains only, if it hasn't got a mains facility it should be run on gas.

The fridge not working on mains (230v) is a second and unrelated issue as the 12v / gas side of the fridge is totally separate to the mains side.

ps. it's not a compressor fridge by any chance, if it is all the above is irrelevant as they are designed run exclusively on 12v from the leisure battery, they don't have gas or mains options at all.

corktina · 22-07-2013 2:44pm

if i had a service manual.!..it's a 1987van..it has wiring like spaghetti...it has fuses at every corner.... it has wires going up and wires coming down and some just for luck that go nowhere....

it's running on my car battery and the mains charger at present.... should work in theory as that should be a sound battery....if it does work, new battery needed...if it doesn't theres another problem there somewhere.

corktina · 22-07-2013 2:49pm

niloc1951 wrote: »

To go back to square one, corktina.

Leisure battery charges when on mains.
Leisure battery goes flat when engine running.

The typical reason for this is a broken connection, or blown fuse, between the engine battery and the leisure battery system.

This is what happens in those circumstances.

Engine starts, alternator starts producing power, relays for fridge and leisure battery close to allow charge to run from the engine battery to the fridge (so it can run on 12v) and the leisure battery (so it will get charged).
However, because of the break in the circuit from the engine battery no power is arriving to either.
But, because both relays have made (closed) and there is a common wire to the engine battery which is not connected to the engine battery (broken connection , blown fuse) the power will flow from the leisure battery direct to the fridge, result flat leisure battery and fridge no longer working.

The fridge not working on mains (230v) is a second and unrelated issue as the 12v / gas side of the fridge is totally separate to the mains side.

it's a 2 way fridge...mains only comes into the picture to charge leisure battery.

AFAIK power does not flow from the vehicle battery to the fridge at any point, that's the point of the relay isn't it? to prevent the vehicle battery being run down ,when the engine stops the relay opens disconnecting the two batteries..
Power from the alternator should do this when the engine is running

niloc1951 · 22-07-2013 3:08pm

corktina wrote: »

it's a 2 way fridge...mains only comes into the picture to charge leisure battery.

AFAIK power does not flow from the vehicle battery to the fridge at any point, that's the point of the relay isn't it? to prevent the vehicle battery being run down ,when the engine stops the relay opens disconnecting the two batteries..
Power from the alternator should do this when the engine is running

Two way.
Mains/gas, mains/12v or gas/12v.

Old two way were gas/12v

See my earlier post. 12v should only operate after the alternator has started producing power. Unless it's a compressor fridge in which case it uses the leisure battery 24/7.

If the alternator charge is getting to the leisure battery you should not have a problem with either type of fridge.

At this time you need to establish the status of the feed from the engine battery, if its charge is arriving at the leisure battery you should be able to measure a rise in voltage to something in the region of 13.6v at least (or the same as the engine battery) when the engine is running, otherwise it's not getting a charging current.

corktina · 22-07-2013 3:20pm

OK thats interesting....at present it is wired so that the fridge is running off the leisure battery as default. The relay connects the leisure battery to the engine battery when you start the engine.

From what you say, it seems you are saying the fridge should only be operating when the engine is running (or on gas)

Will check a few things that occur to me now

corktina · 22-07-2013 4:14pm

OK , rewired the fridge relay back to original. Seems to me the problem was my misconception that the fridge should run on the leisure battery when parked. Niloc pressed the right button in my head, thanks (to everyone)

Now I need get the gas going if that's possible....Aidan MM , can I call on you? Actually the ignitor switch is missing n I'm not sure we'll get anywhere without it.

Once thats done, I might persue the transformer idea as I could then run the fridge from the mains.

22-07-2013 4:15pm

corktina wrote: »

AFAIK power does not flow from the vehicle battery to the fridge at any point, that's the point of the relay isn't it? to prevent the vehicle battery being run down ,when the engine stops the relay opens disconnecting the two batteries..
Power from the alternator should do this when the engine is running

Both batteries and alternator are linked to your fridge with the engine running common positive, common negative. So all 3 are powering your fridge...or I imagine the engine battery and alternator were powering a dead battery and a fridge previously.

The point of that relay is to stop draining the engine battery with the engine off.

You can still get service manuals for old vans. If Haynes don't do them. Try http://www.russek-publications.com/shop/shop.html I bought a paper version for my '70 odd to '95 van there.
Easy enough find factory service manuals online in .pdf on popular vehicles, love these, 1200+ pages

and a separate book for wiring diagrams.

corktina · 22-07-2013 4:19pm

Sir Liamalot wrote: »

The point of that relay is to stop draining the engine battery with the engine off.

what I didn't ppreciate was that this would be by other 12v uses such as lights /radio and that the fridge shouldn't be working off the leisure battery at all. I don't think it's dead btw and should be OK powering just the radio and lights (radio probably works off engine battery anyway if using the standard wiring.

22-07-2013 4:23pm

corktina wrote: »

..it has wiring like spaghetti...it has fuses at every corner.... it has wires going up and wires coming down and some just for luck that go nowhere....

Labels could save you lots of time in the future

corktina · 22-07-2013 4:24pm

m\ybe there were labels 26 years ago

22-07-2013 4:29pm

corktina wrote: »

what I didn't ppreciate was that this would be by other 12v uses such as lights /radio and that the fridge shouldn't be working off the leisure battery at all.

corktina wrote: »

I don't think it's dead btw and should be OK powering just the radio and lights (radio probably works off engine battery anyway if using the standard wiring.

I'd say it's close enough to qualify, don't take my word for it though. Test it anyway.

22-07-2013 4:31pm

corktina wrote: »

m\ybe there were labels 26 years ago

Probably better not have a working fridge. Don't really wanna be leaving food in that place with thems a-maraudin' gremlins aboot!

corktina · 22-07-2013 4:41pm

not a lot of use to me tbh if it wont run the fridge when parked up.... doesnt really matter if it's flat or not now, although it is charging at the moment and showing full voltage already

22-07-2013 5:10pm

corktina wrote: »

not a lot of use to me tbh if it wont run the fridge when parked up

What about the camper discos in the wilderness? You'll be wanting it then!

corktina wrote: »

although it is charging at the moment and showing full voltage already

That's not a good sign. Reduced capacity, only surface charging etc.

Leisure battery

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