12V Jabsco Toilet Draw

[islander20]

Hello,

I just got a great deal on a 12V Jabsco toilet. The pump draws 12V 15 amps, he macerate is around 12V 16A. I am new to boating and understanding power consumption, my question is what size of batteries will I need to run this? Will two 12V battery's hooked up in parallel be sufficient to run these for a reasonable amount of time (2-3 days) at most? Other than a depth sounder, occasional cabin light usage and charging my smartphone there will be no other draws and those latter uses should be pretty infrequent.

Thanks for the help

[Florida Mike]

More than likely the toilet pump only runs a short time with each flush pumping what is in the bowl to the holding tank. The macerate pump should be for pumping the holding tank out. Based on that you’ll find the electoral consumption to be very minimal and lets you flush the toilet 20 times a day. Just my two cents, Mike.

[RUSTYNAIL]

There are a lot of potential variables in your question, mainly how will you charge them to make sure they had a completely full charge, and what do you expect to run in an emergency situation when you get to the end of the two or three days. My concern is that you have enough battery to run a bilge pump, cell phone or VHF radio if needed. The best thing no matter what pair of batteries you buy, would be to invest in a digital voltmeter or low voltage alarm for your panel and never let the batteries get below 12.2 volts so your pump and radio will work for a while. I use a Blue Sea digital voltmeter that's in their catalog with a variable alarm set level, sleep mode to reduce draw when not needed, and big red numbers. I don't think it's in the West Marine catalog. The Blue Sea number is 8251. Unfortunately it will probably cost as much as the two batteries, but you will sleep much better..

[islander20]

Thanks for the replys. There is no space on my boat for a holding tank, the waste is pumped straight out. I know its not allowed in many areas, fortunately it is in mine. I was planning on using the macerator to empty the bowl and flush the waste out. For filling the bowl I was going to hook up a small diaphragm pump on the intake. That should work eh?