2016 C 30 low voltage

[aabbovet]

Hello,

Second time out in our new to us 2016 Cutwater command bridge- ran for 2 hours, arrived at the destination and house battery bank was 10.5 ( boat lives on a mooring and I didn't check battery levels when we left, though did see an intermittent low voltage alarm on autopilot while underway), on arrival started the generator and charged house bank to 13+- held at 12.1-12.5 with periodic charging via generator ( 2x daily while we were on a mooring for 3 days- running the fridge on 1-2)- ran home today, 13.5V on Volvo gauge/ engine battery while running, house bank 12.5 on arrival- but low voltage alarm on Garmin- seemed to occur at idle speed and when increased rpm's appeared to resolve... any ideas, I am admittingly a battery knowledge beginner. We have also been getting a low coolant ( there is not low coolant) and water in fuel error ( also, no water in the fuel) Any ideas or suggestions?

Thank you!

Andy Abbo
ALAEA

 

[BB marine]

Start with batteries. When were the batteries replaced? I'm going to guess the batteries are not new. A two hour run should bring the house batteries to a full charge. I would fully charge the batteries and load test. I believe you will see that the batteries are the problem. If the Volvo gauge is reading 13.5 volts the ACR should be closed and charging all banks. If the house batteries are not fully charged or not charged to 12.75 Volts when the engine rpm drops. The alternator output may not be enough to keep the ACR closed and the house batteries will now not be charged. This will set the low voltage alarm. When the engine rpm increases the engine battery will now reach 13.5 V and the ACR will close again bringing the house batteries back up enough to maintain a voltage high enough to satisfy the Garmin. Sounds like a battery issue.

There is a low coolant sensor. If the coolant is at the proper level and the low coolant alarm or code is shawm on the EVC I would troubleshoot the sensor.

Water in fuel alarm is a troublesome issue. There are several threads about this on TugNuts. There have been post made indicating a fuel additive can cause the issue. There are other post that indicate changing the sensor rids the issue. The first attempt I would do is unplug the sensor and remove it, drain the filter and confirm there is no water in the secondary fuel filter. Drain the primary filter and see if there is any water in that filter. Traces of water will set the alarm off. Reinstall the sensor and prime fuel system to fill filters. If the issue continues replace the filter sensor.

 

[Phil Nersessian]

The low coolant alarm is probably accurate. It is very difficult to see into the fill (need mirror from inside the cabin). when the boat gets winterized Onset Bay disconnects the hot water tank and often loses coolant into bilge. I would try adding some, there should be some on board(volvo). I believe two of your batteries are new( They got broken from being improperly secured). The boat was always on shore power so I can't speak to the charging times.The electrical system is very complicated when it comes to the battery banks etc. and takes awhile to get down ( I never did). I think I I got the "Water in Fuel" twice, it was always inaccurate, however, I checked the water separator to make sure it was empty.

 

[aabbovet]

Thank you! Will keep you posted!

 

[Cutwater28GG]

one thing not mentioned above

were the batt volts fine when you left and did you leave the inverter on with a large draw while you were motoring? perhaps the batteries were drawn down from power use not just not being charged in the first place?