Refrigerator - AC Only or AC & Battery

RobboNJ

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I have a 2008 Sailfish 282, new to me this year. The boat has a small fridge in the cabin. It appears the fridge runs off the batteries, as it is on all the time; when connected to shore power, when not connected to shore power, when the engines are running and when the engines are not running. This does not seem right to me, as it allows the batteries to be drained when not connected to shore power and the engines aren't running. Does anyone know if this is the normal setup/wiring for the refrigerator?

If I set the battery selector to OFF for all batteries, then the refrigerator will not run. However, then nothing else works either.

Thanks for any input on this setup.
 
Check the model number of the fridge. My 1997 Islander has a 12 volt only unit. I converted mine to 12 VDC / 120VAC. Instructions posted here:


For about $30 you can convert existing fridge to dual voltage. Substantially less than a new one. It's nice because you can turn the batteries and charger OFF and fridge will still work.Installed 2/2021 and working fine.
 
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I have a 04 Sailfish and the OEM frig was battery only. If your on shore power the batteries stay charged by the charger. If not on shore power or under power you can drain the battery. Your can turn the frig of with the knob inside the frig toward he back top right. I replace my frig 3 years ago and the newer ones are ac/dc. They automatically flip to AC on shore power and DC underway. If you are worried about the battery while anchored or fishing you can shut the frig off and it stay cold for quite a while.
When I put in the new frig I had to add an electrical outlet in the frig compartment. I just jumped off the outlet in the cabin for power. Now if I wanted to shut off the frig I can use the switch in the frig or the the beaker on the AC panel for outlets.
What year is your SF?
 
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On your DC panel, is there a switch for the fridge?
 
I have a 04 Sailfish and the OEM frig was battery only. If your on shore power the batteries stay charged by the charger. If not on shore power or under power you can drain the battery. Your can turn the frig of with the knob inside the frig toward he back top right. I replace my frig 3 years ago and the newer ones are ac/dc. They automatically flip to AC on shore power and DC underway. If you are worried about the battery while anchored or fishing you can shut the frig off and it stay cold for quite a while.
When I put in the new frig I had to add an electrical outlet in the frig compartment. I just jumped off the outlet in the cabin for power. Now if I wanted to shut off the frig I can use the switch in the frig or the the beaker on the AC panel for outlets.
What year is your SF?
Do you recall what fridge you put in? Mine is original and showing it's age, I was going to see about replacing. The outlet is right there, and like you I was thinking I could just jump off of it and use the breaker for the outlets to do the fridge as well. Probably once a season I'll accidentally leave my fridge on and the battery charger won't be clicked on and it will drain my house bank.
 
Most newer and a lot of older) DC fridges have protection logic that will shut off the fridge if battery voltage drops below a specific level
 
When I'm on a mooring, retiring for the night, generator off - I will turn off the refrigerator. The refrigerator is a major power user, but I've had no problems turning off a cold refrigerator for 7-8 hours. I turn it on again when running or on generator.
 
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Most newer and a lot of older) DC fridges have protection logic that will shut off the fridge if battery voltage drops below a specific level
Low voltage detect is a nice feature. I have to be careful when I get back to the dock to make sure my main breaker doesn't trip and forget to reset it. Otherwise no charger to maintain batteries and power fridge and bait tank pumps. A good charger can handle the fridge load. I've had problems in the past with the fuse holders overheating. That's why I did the conversion. ProMariner has fixed the fuse holder problem on the newer units.
 
The fridge will have an on/off switch (whether inside the fridge or a breaker on your elec panel) - use it :) It sounds like Legend pointed you in the right direction already, though.

As far as draining a battery - they're actually not too bad as long you don't keep opening the door and staring into it like you do at home. Putting more stuff in the fridge helps, as well. I once went 3 days and nights on a single group 27DC - running the fridge the whole time... plus lights and fans at night and some stereo... plus Vacuflush head use. Ran the engine for less than an hour that whole time and it still started the engine just fine on the last day - and that a 350 V8 stern drive, too.
 
The fridge will have an on/off switch (whether inside the fridge or a breaker on your elec panel) - use it :) It sounds like Legend pointed you in the right direction already, though.

As far as draining a battery - they're actually not too bad as long you don't keep opening the door and staring into it like you do at home. Putting more stuff in the fridge helps, as well. I once went 3 days and nights on a single group 27DC - running the fridge the whole time... plus lights and fans at night and some stereo... plus Vacuflush head use. Ran the engine for less than an hour that whole time and it still started the engine just fine on the last day - and that a 350 V8 stern drive, too.
What was your battery type?
 
Thanks for all of the replies. I do have the temparature control knob on the inside, back, top, right. I did not know I can turn off the fridge with that knob! I will take that approach when I am off shore power and not running the engines for a long period of time.

The boat does not have a separate breaker switch for the fridge.

Thanks again!
 
Low voltage detect is a nice feature. I have to be careful when I get back to the dock to make sure my main breaker doesn't trip and forget to reset it. Otherwise no charger to maintain batteries and power fridge and bait tank pumps. A good charger can handle the fridge load. I've had problems in the past with the fuse holders overheating. That's why I did the conversion. ProMariner has fixed the fuse holder problem on the newer units.
The tripped main gets me every season at least once, its a guarantee.
 
It’s a 12v dc fridge. You can run it when on shore power and when engines are running no prob. Can also run on the hook or when engines are off but you’ll drain the battery.
 
I have also experienced the tripped main, only it wasn't tripped. I turned it off myself and then forgot to flip it back on. Next time I boarded the boat the house batteries were dead!. Thank goodness for the battery switch. Was able to start everything off the third battery, charged up the house, and was good to go (and switched the Main to ON!).
 
I have also experienced the tripped main, only it wasn't tripped. I turned it off myself and then forgot to flip it back on. Next time I boarded the boat the house batteries were dead!. Thank goodness for the battery switch. Was able to start everything off the third battery, charged up the house, and was good to go (and switched the Main to ON!).
Amen to the Battery switch, has saved my bacon a couple times.
 
If the fridge is cold and fully stocked with cold items it will stay cold for a while. In thi situation it will use minimal power. For day fishing trips, island and sandbar Tripp’s I have never worried about leaving the fridge on. After a couple of days in the summer sun it will run the battery down. But for normal use I never turn it off.
 
I have a 04 Sailfish and the OEM frig was battery only. If your on shore power the batteries stay charged by the charger. If not on shore power or under power you can drain the battery. Your can turn the frig of with the knob inside the frig toward he back top right. I replace my frig 3 years ago and the newer ones are ac/dc. They automatically flip to AC on shore power and DC underway. If you are worried about the battery while anchored or fishing you can shut the frig off and it stay cold for quite a while.
When I put in the new frig I had to add an electrical outlet in the frig compartment. I just jumped off the outlet in the cabin for power. Now if I wanted to shut off the frig I can use the switch in the frig or the the beaker on the AC panel for outlets.
What year is your SF?
Do you have any info on the new frig you used? The frig in my 03 is dead. Thanks.
 
Do you have any info on the new frig you used? The frig in my 03 is dead. Thanks.
Congrats on your Sailfish it is a great boat. Her is the frig info - it is the exact same size and brand that was in the boat originally. Does the light in your frig go on when you open the door. If not it could be a fuse. The fuse is under the helm an the 04SF. If the light is on the frig could be turned off. on my original model the switch is at the back of the inside of the frig on the right side. it is a knob switch - all the way to one side it ends with a click all the way to the other side dictates how cold you want it.
If all that fails here is the current model # - Good Luck
ISOTHERM Cruise 49 Elegance BlackIsotherm Refrigerator
C049RBBAB71113A
 
Congrats on your Sailfish it is a great boat. Her is the frig info - it is the exact same size and brand that was in the boat originally. Does the light in your frig go on when you open the door. If not it could be a fuse. The fuse is under the helm an the 04SF. If the light is on the frig could be turned off. on my original model the switch is at the back of the inside of the frig on the right side. it is a knob switch - all the way to one side it ends with a click all the way to the other side dictates how cold you want it.
If all that fails here is the current model # - Good Luck
ISOTHERM Cruise 49 Elegance BlackIsotherm Refrigerator
C049RBBAB71113A
Thank you. No the light doesn't come on, so I hope its a fuse. Just got to figure out which one. I did find the dial inside and set it to the middle so I would know it's on, and haven't noticed it getting cooler . So next step is the fuse, then deciding if I want to spend $1000+ for a new frig. Thanks again for the info!
 
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I could probably do my homework to answer this myself, but I'm sure someone else here already knows the answers.
- Will the engine's charging system (f150) put out more power than the draw of the fridge so while underway the charging system can maintain and replenish what the fridge used?
- If I don't have shore power would a typical onboard charger provide enough current to keep the fridge going while topping off the battery - say if I plugged the charger into a portable genny? (Yes, I know the dangers of these) If so, is this detrimental to the charger?