Batteries not operating normal since solar installation

[Laceynhans]

Good morning
I need help from some electrical gurus. I recently installed 590watt solar in parallel with a victron 100/50 controller connected to 2 8d deep cycles of "fair condition" . Yeah solar!! Happy days. Within a week I notice my fridge, keel cooled fridgeoboat, starts and stops immediately all night long, batteries still 12.5 ish. Manual says may be an amperage issue, call technician. But fridge works like a champ all day..hmmm. Now, another week later, house batteries will no longer crank my engine over. Perhaps is is coincidence but It seems to closely connected. As luck would have it my engine start (designated and completely separated) is not holding charge, so the only way to crank engine is to plug generator in and "jump" the engine, even though house batteries are charging or floating at 14+. Thanks for any thoughts

[Pete7]

Batteries knackered or wiring isn't sufficiently heavy duty so fridge draws too much current at 12.5v but just enough from the genny at 14.5. Is the wiring from the panels and MPPT also heavy duty or something more akin to bicycle wiring?

Pete

[Laceynhans]

Fridge used to work before solar all the way down to 11.5, solar is wired with 10awg less than 15ft. I tested batteries yesterday and all cells were "fair". A bit low on fluid so I added some distilled water.

[Pete7]

Do you nomally take the battereis down to 11.5v, if so that is why they are probably kaput.

How did you test the batteries?

Pete

[jamhass]

Try disconnecting the solar to help isolate the problem in case the solar is the issue

[Laceynhans]

Tested each battery cell with hydrometer, dot usually pull batteries below 12. Tried disconnecting solar to see if the fully charged house system would then start engine..but alas no. Perhaps I have a separate connection issue to engine starter, but there is voltage at starter.

[Pete7]

Originally Posted by jamhass

Try disconnecting the solar to help isolate the problem in case the solar is the issue

Yep, good idea. I suspect the solar is keeping the fridge running during the day, but at night the batteries can't cope.

Pete

[Laceynhans]

Currently more important, but likely connected, is why will my house batteries suddenly not start my engine?

[Pete7]

They can't supply the ampherage to start the engine, there at the end of life.

Pete

[Laceynhans]

Ok, that was my thought, also with the fridge, but they still test at 'fair'. Does fair mean caputz? And they are under a year old. We have been fairly abusive to them, but not extreme. So the panels are in Parallel right now, adding more amps less volts. Any logic to switching to series? Adding more volts and same amps? Sorry for my ignorance but this is really confusing me

[Suijin]

It sounds like the timing is just coincidence.

It's not hard to trash your batteries in a year with chronically abusive drawdown and charging habits. If you routinely take them down to 11.5 and are not fully floating them off on an adequate schedule that would most certainly do it.

[1affiah]

You should start by cleaning all of the battery terminals, both pos & neg, and check all wiring connections between the batteries, solar, fridge, engine & grounds, etc.

[captstu]

Sounds like one or more cells may be low on water - or dirty connections.

If you are seeing nominal (12.2 to 12.7 volts) with the fridge running, try covering the cells with a towel and see if the voltage drops significantly. If so, you have a failing cell.

[CaptRory]

I don't know about your set up... But remember, if you do not have the appropriate diodes in there, the current reverses in the dark and you send your stored power back out into space.

[senormechanico]

My first thought as well.
You did wiring stuff, probably a main battery cable connection somewhere along the line got disconnected and not properly reconnected, or an iffy connection got disturbed.
Check every primary battery cable at the connections and splices if any.