Sub Zero Ref/Fre

M

Max_L

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I currently have two under counter Sub Zero's. Does Sub zero make a 120/12v series now? If not, what is a good replacemnet for them? We do a few weeks on the hook and I don't like running the genny all of the time.

Also, I have one seal that is not tight on the refrigerator. Is there a place that I can pick up a new door seal for it?

Thanks in advance,
 
i dont' think they make 12v/120v units, why dont' you just put in an inverter? cheaper than replacing those units and you can power other things too...

check with subzero or one of their dealers for the seal, but first make sure it's not the cabinetry interfering.
 
I did put in a Xantrax, Prosine 2.0, with 6 deep cycle golf cart batteries and 2 interstate deep cycle that were already in the boat. I have about 2000 amp hours or greater total. I wanted 15 hours of half battery life running my Sub Zero's, TV, DVD and a few other things while on the hook. Run the genny for about 2 to 3 hours heating up water, watch a movie, ect and it charges the batteries back to full capacity. It will run one AC but cuts down the battery usage very fast (still haven't done all the math yet).

I was just curious about the Sub Zero's for future consideration. If we stay with Sub Zero we will just go down to the one that is ref/frez together. We don't need a full freezer. Longest we are ever out of port is about a week and half.

I will try and contact one of their dealers for the seal. I have checked the cabinet and nothing is hitting or binding, seal is just old and the most amount of use.

Thanks
 
6 golf cart batteries will only give you about 660AH rb2@gr5t 12v, or about 330AH usable. dont' know where you get your "2000 amp hours or greater total". Even if the two deep cycles were 8Ds, that's still just another 400AH or so. Plus, it's never a good idea to mix battery sizes in a bank, so i assume you have the golf cart batteries in a separate bank.

how many subzeros do you have? two of them? if you only run one, you may be able to get 15 to 18 hours, just.

on my boat, I run a full size 18cu ft fridge freezer fro about 18 hours, plus lights, TV, etc... on 8 golf cart batteries.

I installed a 4KW magnum and 16 Golf cart batteries on the 70 footer I captain and we get about 18 hours running 3 subzeros, 1 Uline Ice Maker Fridge, and the lights, TV, etc...

forget running air con on the inverter, you're going to drain teh bank very quickly, plus i doubt your 2000w inverter can power the subzero plus the AC together...

even if you could switch to 12v refrigeration, there is no miracle. it takes teh same amount of power to cool a fridge and freezer, whether at 12v or 120V. the only thing you may gain i eliminating the 10% inverter loss, but that's not worth it. jsut add another pair of batteries or two
 
You'd have to run the genny to rechargethe batteries for the inverter. Fix the seal. If we run the genny till 10 or 11 at night and then fire it up in the morning, the fridge and freezer are still cold. Genny's are made to run and run and run.

I agree, I'd like to replace the freezer with a refer freezer combo, but sub z units are EXPENSIVE. I would think that if you spend weeks on the hook that you would have a lot of frozen food.
 
a good solution for freezers if you dont' want to rely on AC power are cold plate system. 3 to 4 hours of genset runtime a day is enough to keep a cold plate freezer below freezing. If you stay on the hook for a week at a time, it's a great solution. (if you have room somewhere, they do need heavy insulation)
 
"I installed a 4KW magnum and 16 Golf cart batteries on the 70 footer I captain and we get about 18 hours running 3 subzeros, 1 Uline Ice Maker Fridge, and the lights, TV, etc..."

How long do you have to run the genset to recharge the bank from 50% down?

Approximately what did it cost, including labor, to set the system up?
 
we run the genny 4 to 5 hours a day if down to 50%...

the inverter was about $2000, about the same for batteries and maybe under $500 for all the 4/0 cable, terminals, wire, etc...

I had gotten a quote from a reputable "marine electrician", he wanted about $5000 of labor for the job and batteries where marked up 100%... it was true sticker shock territory, the quote was well over $10k!

It took me about 3 to 4 days to install everything...
 
I have two sub zero's, one is a freezer and the other is refrigerator. We don't run the ice maker even with the genny. The banks are separate, Interstate on one and golf batteries on another. My 8d's are on another just for the engines with it's own charging system. I used the 225 amp hours on each of the golf batteries and the 600 hours on the deep cycle interstates, to come up with my totals. That gave me 1950 amp hours. I guess I was wrong.

I don't run the a/c or would I because of the drain but we were surprised that it (inverter, has 4500 surge ability) actually would run the sub zero's and one of the a/c's. Of course the drain on the battery's would probably deplete them in about 3 hours. If not sooner.
 
Another thing to consider is improving refer discipline. Most refers use power not because of heat flow through their insulation but because of doors being opened. Considerable power savings can be had for free if the doors don’t get opened every time somebody needs ice or a coke.
Consider some method of not opening the big boxes after you shut down the genny such as adding a smaller day box, or even a cooler for those times when you are on the hook.
 
Max, golf cart batteries are about 220AH each, but that's at 6v. when you put batteries in series, voltage goes up but not amps, so a pair of GC in series gives you 12v instead of 6 but still 220AH. so when you parallel your 3 pairs will get you 660AH.

if your inverter was 24volt, you have to stick with sets of 4, so that would be 4 batteries, 8, 12, 16, etc... four batteries in series will give you 24volts but still 220AH. In my case we have four sets paralleled together for 880AH but at 24v. and 880AH rb2@gr5t 24v is twice the power than 880H rb2@gr5t 12v...

and obviuously you cant add batteries in other banks (starting) since they're not connected.

660AH is a little light in your case considering the loads, if you have room, you may want to add an extra pair.
 
If you have the height, L16 floor scrubber batteries are a great way to get extra amp hours out of the same floor space. That's the route I was able to take, getting 400AH at 24v out of four of them. You can't add these on to an existing bank of GCs, however, as they have a different charging profile.

I power a full size home style Sub Zero side by side, plus two wine cooler style beverage coolers, typically for 8 or 9 hours depending on temperature and what other stuff gets used (TV, Computers, halogen salon lights, microwave, coffee maker, etc). Since we typically run the genset for a few hours first thing in the morning and last thing at night, for cooking, laundry, ice making, etc, that works for us. I have an Automatic Generator Starter, along with a Battery Monitor Kit, networked into my Magnum inverter system; I can set the AGS to kick in at whatever bank voltage I choose and run the genny for any preset time I choose. Genset is a 20kw Onan.

I am sure there may be exceptions, but every 12v/120volt refrigerator (and some "pure 12 volt" versions) I have ever seen is "12 volt" by means of a built in inverter... little to no gain in efficiency.

George
Hatteras 56MY
 
We do carry a small cooler for the soda and some cold water and try to keep the ref closed as much as possible.

My inverter/charger is a 12volt system.

How many amps does the SubZ's pull per hour? I went to their web site and they only talk about annual expenditure not amp hours. I looked in my manuals and couldn't find any reference either.
 
you can look at the mfg label on the refer for maximum amps but a good refer runs only a fraction of the time. Only you can figure out how much time it actually runs under your use conditions during any time period.
You might be able to back into an estimate from the annual expense if they give the KWH cost used for their estimate.

What mfg data do you have??
 
I looked it up. The model 700BC says $41 per year based on $.096 per kWH

Unless I blew a number along the way that equals 48 watts average load at 120V or 0.4 Amps or 4 Amps at 12VDC at 15 Hours that is only 60 AH assuming your door opening frequency is similar to theirs.

The TV however is another story. LCD TV power is hard to come buy but I found some estimates
LCD TV 200 watts and the old CRT type should be about 800 watts or more
200/12=16A or 64 Amps for the old CRT Tvs.

I think your other stuff is the culprit in your power use.
 
bruce,

I dont' know about your numbers :) no way a subzero only uses 60AH at 12v in 15 hours... that I am sure about, from actual experience...

I looked on the back of an old 21" Sony Trinitron I have in my room here on the hatt., the label says 120W max. granted, 21" isnt' that big but a larger CRT isnt' goign to pull 800W !!
 
Taking all of the figures, running my 32" LCD, stereo (surround sound),dvd and Subz's. We're using about 400 amps for 15 hours.
In reality at night we have the genny running watching a movie while the batteries are charging. The longest single item running will be the Subz's running through the night for about 10 hours until am then the genny goes back on for breakfast and another charge.
From what I see the Subz's will use somewhere around 40 to 50 amps.

That should work. I'm going to do some trials at the dock over the next couple of weeks. Then we will be heading out for about 3 weeks.
 
Pascal: I understand however unless I slipped a decimal that is how $41 at 9.6 cents a KWH works out. I do know that the duty cycle of my home refer is quite low.

Here is the LCD TV data for newer energy star sets, strangly the Samsung, Sony and JVC dont give data just energy star ratings.
http://reviews.cnet.com/green-tech/tv-consumption-chart/
Not much CRT Tv data around but LCDs are refered to as using 60% less in some discuussions

And here is some refer data. All over the map but smaller units are down to 50 watts, so maybe subzero data is close, take your pick.

http://www.absak.com/library/power-consumption-table
 
With regard to the system Pascal described above, I hate to tell you, but with the entertainment system breaker on (but the tv's, etc. not in use but in sleep mode) it's more like 10 hours to run the batteries down to 50% from fully charged. I tested extensively last week. With it off there is plenty of juice for two SubZero fridge drawers, the SubZero freezer drawer, wine fridge and the fridge in the cockpit for 18-20 hours. Total charge time from 50% is about 6 hours.
 
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