Parasitic loads on house batteries

[kjoverbeck]

I recently installed 4 new batteries. All had the same voltage. I then turned on the house but left the engine and thruster batteries off. My charger was off. Several days later I checked and the house batteries were slightly lower than the others, 1/2 v. All 12 volt breakers were off. Question is that when all 12 volt is off, just what is still on using energy?
Thanks, Kent

 

[Mr. Ed]

I had a similar problem when I picked up my new R31S. The rotary inverter switch was left on, and it drained the house battery bank. Turning it off solved the drain. Hope this helps!

 

[j&lgray]

First, all the bilge pumps are directly wired to the battery.

The electrical engineer who designed the Ranger and Cutwater line of boats made some interesting design decisions. You can turn off all the DC breakers but that does not cut power to host of 12 volt users. There are several fuse blocks that feed instrumentation, VHF radio, Fusion radio, the electric head, cabin fans, and more. Those circuits are energized.

If you leave the NMEA network or the propane solenoid energized, those will noticeable draw down the house battery.

All of this is not an issue if the boat is running or on shore power or the solar panel is working. But if the boat is being stored with shorepower, the best strategy to preserve the batteries is to disconnect them by removing the cables at the terminals.

 

[kjoverbeck]

Thanks Ed and John. I'm covered on all except not sure about the propane solenoid. Will check it out. By the way, all 12 volt outlets also remain on. I am on shorepower so no big deal.

Kent

 

[jagizzi]

My 23 has an always hot fuseblock that seems to be dedicated to the parasitic loads. I would guess that the 27 is the same but I don't know where it is located on your boat. On the 23 it is in the cave behind a velcro'd wall panel.

Once the fuses in that panel are pulled I am good for winter storage with no shorepower.

 

[kjoverbeck]

Propane solenoid was off. I actually only had a 1-2 tenths of volt difference so I think all will be OK.

 

[Skeeter]

I have the rotary switch to the inverter turned off, however, I have a similar problem 2112 R27. We have the Morningstar meter. After running both house batteries show 12.9 volts (lead/acid). At night we turn everything off. Batteries are both reading 12.7 volts. In the morning, house battery 1 is sitting at 9.x volts, not enough to power on the diesel heater or frig. House battery 2 is still showing 12.7 volts. Since both batteries are in parallel, shouldn't both batteries allow the heater and frig to start running without having to bump up the voltage on house battery 1? Running the engine for 10 minutes, brings house battery 1 back up to 12.7 and the diesel heater and frig can be turned on. Will be replacing all my batteries this spring with AGM, any suggestions on brand?

 

[Red Raven]

I have the rotary switch to the inverter turned off, however, I have a similar problem 2112 R27. We have the Morningstar meter. After running both house batteries show 12.9 volts (lead/acid). At night we turn everything off. Batteries are both reading 12.7 volts. In the morning, house battery 1 is sitting at 9.x volts, not enough to power on the diesel heater or frig. House battery 2 is still showing 12.7 volts. Since both batteries are in parallel, shouldn't both batteries allow the heater and frig to start running without having to bump up the voltage on house battery 1? Running the engine for 10 minutes, brings house battery 1 back up to 12.7 and the diesel heater and frig can be turned on. Will be replacing all my batteries this spring with AGM, any suggestions on brand?

The battery number 2 on the Morningstar remote is the Engine battery. That is why it is a different voltage than the house. Both house batteries are tied together in parallel as one bank and as such cannot be measured separately.

Curt