12.5 V but no amperage?

[squaw999]

batteries 12.5 V, but no amperage to switch on frig compressor! Should I buy a new batteries?

[thomm225]

Originally Posted by squaw999

batteries 12.5 V, but no amperage to switch on frig compressor! Should I buy a new batteries?

Could be the connections. Check or redo the connections at the battery.

It's like on your car when the voltage reads properly on the gauge, but then when you turn the key nothing happens besides maybe a click. (and the voltage drops to zero, then back up)

On my oldest Jeep, I just knock the terminals around a bit then it will start.

I have since replaced both terminals and cleaned the battery posts.

[squaw999]

20 minutes after the sun rises, the compressor starts working without any intervention. 2 x 100 W solar panels

[Bill O]

Maybe your batteries are toast since the fridge starts up w/solar input. Is everything else running (electrically), if the batts are low? If so, would trouble shoot the electric to the compressor. How big is you house bank and what type of amp draw is from the compressor when running?

Are you certain the batteries are at 12.5V and not lower? Did you take that reading at the battery?

Until you get new batts, would turn off at night if you can safely maintain good fridge temps.

[squaw999]

Just frig running. 2 x 140 Ah. Batts never under 12.3 V. When starting (about 1-2 min), 7 Amp. After, 3-4 Amp.

[Snore]

For voltage, but no amperage, I would check the following:

• Cable Size vs what the manufacturer recommends for the length run.
• Unless YOU installed the cable, trace the run. Make sure there are no irregularities along the run.
• Disassemble and clean any mechanical connections.

If the boat is new-to-you check the wire first. I had an autopilot that kept dropping out. Turned out the previous owner used lamp wire to supply it.

If this is a new problem, then trace the line for odd connections and disassemble and clean any mechanical connections. I am assuming there are no crimped connections.

[Bill O]

In addition to above suggested checks, if these are FLAs, would check water level in cells.
How old are the batts? Any idea of the daily ah draw from the fridge?

[capt jgw]

Originally Posted by Bill O

In addition to above suggested checks, if these are FLAs, would check water level in cells.
How old are the batts? Any idea of the daily ah draw from the fridge?

If they're sealed lead acid that doesn't mean they're not low. They can vent if overcharged and you can't check or replenish them.

[squaw999]

Originally Posted by capt jgw

If they're sealed lead acid that doesn't mean they're not low. They vent like unsealed, just slower and you can't check or replenish them.

Lead acid. 2 years old

[capt jgw]

Originally Posted by squaw999

Lead acid. 2 years old

I take it you mean unsealed, with vent caps. Yes, check the water.

[noelex 77]

You have not mentioned where the voltage is being measured.

Check the voltage when the fridge is on and trying to start, both at the battery and at the fridge itself.

If the voltage is low at the battery and at the fridge, this suggests a defective battery.

If the voltage is low at the fridge and the battery voltage is normal, this suggests a defective connection between the batteries and the fridge.

If the battery voltage is normal at the fridge and at the battery, and the fridge is not starting, it suggests a defective fridge.

The above is not foolproof, but it is a simple check only involving measuring voltage and it will likely show where the problem lies.

[gonesail]

if they have boiled to low water .. they can hold voltage but still be bad.

[squaw999]

Originally Posted by noelex 77

You have not mentioned where the voltage is being measured.



Check the voltage when the fridge is on and trying to start, both at the battery and at the fridge itself.



If the voltage is low at the battery and at the fridge, this suggests a defective battery.



If the voltage is low at the fridge and the battery voltage is normal, this suggests a defective connection between the batteries and the fridge.



If the battery voltage is normal at the fridge and at the battery, and the fridge is not starting, it suggests a defective fridge.



The above is not foolproof, but it is a simple check only involving measuring voltage and it will likely show where the problem lies.

Voltage is measured on batts.

[markcouz]

If the fridge has electronic controller then there is often a minimum voltage setting at which point the compressor will shut off in order to protect your battery.

If this setting is available then try setting it lower (eg 10.5v) and see if it will run when solar nit available.

If this works then you should still check volt drop to confirm that it is not excessive.

[noelex 77]

Originally Posted by squaw999

Voltage is measured on batts.

You need to measure the voltage at the fridge itself as well.

The most likely cause of your problems is a poor connection between the battery and the fridge. If the voltage is low at the fridge (when the fridge is trying to start), but normal at the batteries it will confirm this hypothesis.