12.2/3 volts in the morning ?

[grafozz]

every morning when I check the battery monitors (2) they show around 12.2/3 volts ,
the only things running at night are the fridge which uses 2.5 amps whilst running , and the nav light , led Nova .3 amp .
are my batteries dying ?
I have 2 x banks of 2 x 85 amp batteries - none more than 3 years old .

during the day with solar panels and engines running they show around 12.9 v / 13 v ,
is the low voltage in the morning a sign that the batteries are failing ?

 

[RichardS]

You need to turn the fridge and any other electrics off and let the batteries stand for 30 minutes or so. You will probably see the voltage rise up to 12.4 - 12.5 volts which would suggest that all is OK.

Richard

 

[tri39]

No. That's a respectable voltage after leaving the fridge on all night. I switch mine off at night!

 

[maby]

13v is a bit low for a battery on charge. Our bank gets up to over 14v when on charge (shore power) - if yours are not going over 13v, that suggests that they are not getting fully charged.

 

[GHA]

every morning when I check the battery monitors (2) they show around 12.2/3 volts ,
the only things running at night are the fridge which uses 2.5 amps whilst running , and the nav light , led Nova .3 amp .
are my batteries dying ?
I have 2 x banks of 2 x 85 amp batteries - none more than 3 years old .

during the day with solar panels and engines running they show around 12.9 v / 13 v ,
is the low voltage in the morning a sign that the batteries are failing ?

Is that when the fridge is running or off?

Even if off it sounds a little bit on the low side imho. Though if they're only getting up to 12.9/13v during the day then they won't have time to get back up to full charge.


Batteries don't like that...

 

[maby]

Is that when the fridge is running or off?

Even if off it sounds a little bit on the low side imho. Though if they're only getting up to 12.9/13v during the day then they won't have time to get back up to full charge.


Batteries don't like that...

They certainly don't! You need to review your charging arrangements first - the batteries may be dead but if you don't have sufficient charging capacity, you will soon kill the replacements. Take the batteries out and try charging them with a good mains charger to confirm that they will take a charge and see how well they hold it.

 

[JumbleDuck]

No. That's a respectable voltage after leaving the fridge on all night. I switch mine off at night!

Even having three LED interior light on brings my batteries, which are almost new, down to 12.5V or so. They soon recover when things are switched off.

 

[johnalison]

I had two 70hr batteries for service and found a great improvement by adding a third, resulting in lower voltage drops and longer battery life.

 

[Robin]

No. That's a respectable voltage after leaving the fridge on all night. I switch mine off at night!

With respect, then you do not really have a fridge, just another locker.

 

[alan_d]

With respect, then you do not really have a fridge, just another locker.

Really? Then he has an insulated locker with a cooling-plate in it which can be used when there are sufficient amps available. Quite useful, I find. But then I sail somewhere where the nights are cool and the days often not much better. I am sure It wouldn't do in Florida.

 

[grafozz]

I had two 70hr batteries for service and found a great improvement by adding a third, resulting in lower voltage drops and longer battery life.

Yes I have a good spare 105 a/hr battery , I will try adding it to see if it makes a difference , thanks

 

[macd]

You need to turn the fridge and any other electrics off and let the batteries stand for 30 minutes or so. You will probably see the voltage rise up to 12.4 - 12.5 volts which would suggest that all is OK.

+1.
Besides, 12.2 to 12.3V is around 60% charged, which isn't so bad...especially considering that the OP's charging arrangement is so flimsy. I doubt the batteries ever get beyond 80% charged to begin with, and possibly not even that. Ideally the engine regulator needs to put in 14.4V, and certainly much close to 14V than the set-up he describes.

As maby wrote, the charging arangement needs a thorough review before the OP even thinks of throwing money at new batteries.

 

[garvellachs]

Yes I have a good spare 105 a/hr battery , I will try adding it to see if it makes a difference , thanks

Putting another but different battery in parallel may complicate matters? It's easier if they are all identical (in age too).

Are you really saying you see only 12.9v when the engine is running in the morning after running the fridge all night? Do you normally use shore power to charge and this is an occasional thing? I just wonder where these batteries are getting any charge at all?

 

[DannyB]

How are you measuring the voltage, if it's a fixed voltmeter, have you checked the reading with another voltmeter? My voltmeter consistently reads low compared to my digital multimeter.

 

[lw395]

How are you measuring the voltage, if it's a fixed voltmeter, have you checked the reading with another voltmeter? My voltmeter consistently reads low compared to my digital multimeter.

As well as the DC calibration of the meter, it sometimes pays to consider the response to noise and so forth.
If the alternator is putting out a very rough waveform, the average may be 12.9V but the battery is being charged by the peaks.
Some meters will give some information on this if you switch to AC VOLTS instead of DC.
Compare with your car when it's running perhaps?
An alternator with one bad diode might explain a lot?
Also see if it varies with engine RPM.

It sounds to me like the battery is getting charged quite well despite the indicated low charge voltage.

 

[Birdseye]

every morning when I check the battery monitors (2) they show around 12.2/3 volts ,
the only things running at night are the fridge which uses 2.5 amps whilst running , and the nav light , led Nova .3 amp .
are my batteries dying ?
I have 2 x banks of 2 x 85 amp batteries - none more than 3 years old .

during the day with solar panels and engines running they show around 12.9 v / 13 v ,
is the low voltage in the morning a sign that the batteries are failing ?

Best approach it a bit more scientifically. Remove one battery and fully charge it. Then apply a given load - I use an old style car headlamp bulb. Monitor the voltage and time the fall down to 12.25 which is about 50% discharged. Multiply the load in amps by the time by two and you will have a rough guide to the capacity remaining in your battery. Repeat with the other battery.

 

[blackbeard]

FWIW - I have a Waeco fridge and two 80 Ah house batteries. Often down to 12.3 v (with the fridge enjoying a brief "off" period) or thereabouts but rapidly come up if I run the engine (as for instance manoevring in/out of marina) - at first I see about 13.something volts when charging but that rapidly comes up to 14 or so. Batteries are a few years old now. I tell myself not to worry and they are OK for a bit more service.

Incidentally the easiest way to check volts is the inbuilt voltmeter of the GPS but that itself will drag the voltage down a bit.