Battery Question - 21EC

[Pearl]

I currently have two 6 volt golf cart batteries which operates both my AC and coffee maker. What I would like to do is move the two golf cart batteries to where the house and the starting battery are currently located. I would then move the starting battery to the location of the AC batteries.

The reason for moving the batteries is my boat now lists to port because of the golf cart batteries.

I would be operating the house, AC, and coffee maker with the two golf cart batteries, what I would like to know is this possible?

 

[SGIDAVE]

Since your two 6 V golf cart batteries currently supply the coffee maker and the air conditioning, it sounds like you're asking whether adding house loads to the same batteries is okay. And the answer is a definite "it depends." If house loads are low or you don't use air conditioning at the same time you're running significant house loads then there shouldn't be a problem. If, however, you're running coffeemaker (which means an inverter, right?), air-conditioning, and house loads to include refrigerator, your batteries are going to be really stressed out. Running the diesel engine in adding amps back to the batteries through it's alternator will help, however, the amp draw of the air-conditioning is considerable and I doubt the alternator will be able to keep up.

Let us know how it works out,

Dave

 

[Pearl]

Thank you for the reply. I use the air conditioner only when I am on shore power. The coffee maker is a 900 watt Mr Coffee K-cup machine that gets used a few times a day. The reason I installed the golf cart batteries was because I would get a low voltage alarm on the inverter when making a cup coffee. I also changed out the cables (#1 gauge) that run from the batteries to the inverter.

It seems a bit of a waste to run the AC and make a few cups of coffee on these big (232 amp hours instead of 70 amp hours) golf cart batteries and not connect the house loads to them also. I have heard from one fellow Tug-nutter who has moved the starting battery to the location of the AC batteries and placed two golf cart batteries where the starting and house batteries are located under the engine.

I am hoping to hear from Factory Support on this one.

 

[SGIDAVE]

Thank you for the reply. I use the air conditioner only when I am on shore power. The coffee maker is a 900 watt Mr Coffee K-cup machine that gets used a few times a day. The reason I installed the golf cart batteries was because I would get a low voltage alarm on the inverter when making a cup coffee. I also changed out the cables (#1 gauge) that run from the batteries to the inverter.

It seems a bit of a waste to run the AC and make a few cups of coffee on these big (232 amp hours instead of 70 amp hours) golf cart batteries and not connect the house loads to them also. I have heard from one fellow Tug-nutter who has moved the starting battery to the location of the AC batteries and placed two golf cart batteries where the starting and house batteries are located under the engine.

I am hoping to hear from Factory Support on this one.

Hello Pearl,

Well, if your AC is 120 VAC which you run off shore power - NOT the 12 VDC kind the factory used (still uses?), the DEFINITELY, your bank of (2) 6 V golf cart batteries will handle "house" and inverter loads for the coffee maker. Last I knew, the factory was using a 12 VDC Mermaid Marine AC system on the 21ECs, so you need to clarify...since the DC powered AC is consuming more amps than the shore-powered charger can put back (20 Amp charger), the "AC bank" is going to run low in 6-8 hours of continuous AC use. Is your inverter inside the pilot house?

Locating the main battery bank inside the engine enclosure is fine...just rather HOT which is why I moved mine to the AFT/Port location.

dave

 

[Pearl]

Dave,
I do have the factory installed AC and the inverter is inside the pilot house.

Thank you, Eric