Reply
 
Thread Tools Search this Thread Display Modes
 
Old 06-12-2021, 11:49 AM   #1
Guru
 
kthoennes's Avatar
 
City: Sioux Falls, South Dakota
Vessel Name: Xanadu
Vessel Model: Mainship 37 Motor Yacht
Join Date: Oct 2013
Posts: 2,471
New refrigerator, time for a new battery charger - advice?

Sorry to start yet another refrigerator thread, but our old Norcold DE 461 died. Original to the boat, 1996, so I guess I can't be too annoyed, worked for 25 years. I did try some of the advice on past threads for getting it working again, but I'm giving up, and it's rusting out around the edges anyway. By the time I add shipping and tax and incidental installation stuff I'm not in the mood to spend $1,500 or more on the DE 061, so I finally found a 110v AC household fridge that matches the cabinet size within an inch or two all around. The LG LRONC0705V, single-door, 6.9 cu ft. I can order it through Home Depot for $499, free shipping, delivered to my house. Door swings the wrong way and it can't be changed, but with our galley layout that doesn't matter much. The dimensions are very close to the Norcold but slightly smaller all around so I don't have to do a big carpentry project, maybe just some trim or retainer pads to hold the new one securely and make it look pretty. I'll also have room inside the cabinet to add a vent fan this time. But that brings me to power...

I can't find the draw (watts) for that LG anywhere, I'll have to figure that out when I get it, but the Energy Star label shows it's rated at 220kWh per year, which is relatively low. The 110v connection will be easy of course, for when we're on shore power. And then we'll need a DC to AC inverter for 12v operation, but all that's a lead-up to: As long as I'm doing all this, it's probably time to upgrade the battery charger. We have a Dytek "Marine Automatic" battery charger and I've pasted the spec plate below. Still works well as far as I know and we've never had any problems with it, but I assume it's at least 25 years old too (or 26 years old, if that date code means 1995). Although I get the basics, I'm really not good at electrical, my brain just doesn't work that way, so I defer to the many experts on here who know more about electricity than Nikola Tesla ever knew:

What new battery charger should I buy?
Attached Thumbnails
Dytek Batt Charger.jpg  
kthoennes is offline   Reply With Quote
Old 06-12-2021, 12:01 PM   #2
Guru
 
Xlantic's Avatar
 
City: Mahón, Menorca
Vessel Name: Halcyon
Vessel Model: 1973 Grand Banks 50
Join Date: Mar 2015
Posts: 517
I think what you need is an inverter so you have AC for the fridge when you don't have shore power or the generator running.

You need to see what the maximum watts the fridge requires, plus any other AC loads you may want to have, and size the inverter to that.

For little extra cost over that of an inverter you might buy an inverter-charger. If you go this route you can keep your current charger and use both to charge your house batteries faster when on the generator.
__________________
Gilberto
Xlantic is offline   Reply With Quote
Old 06-12-2021, 12:51 PM   #3
Guru
 
rgano's Avatar
 
City: Southport, FL near Panama City
Vessel Name: FROLIC
Vessel Model: Mainship 30 Pilot II since 2015. GB-42 1986-2015. Former Unlimited Tonnage Master
Join Date: Oct 2007
Posts: 4,977
I would guess that old battery charger is not anywhere near as capable as the newer generation chargers. I am happy with the Pronautic 50-Amp, variable power out charger I have. What size house battery bank do you have to support an AC reefer? I big monster inverter/charger is not required if all you are running is the reefer. I used an 850-watt inverter about the size of a couple of cartons of cigarettes to power my under-counter AC reefer and preferred a separate charger to avoid the possibility of have both my inverter and charging capability go down if the inverter/charger unit quit.
__________________
Rich Gano
FROLIC (2005 MainShip 30 Pilot II)
Panama City area
rgano is offline   Reply With Quote
Old 06-12-2021, 01:30 PM   #4
Senior Member
 
City: Cairns
Join Date: Jul 2019
Posts: 499
Slightly off topic but with such a close fitting new fridge is there enough space for cooling? Many new models need clearance around all sides not just the back

Cheers.
GoneDiving is offline   Reply With Quote
Old 06-12-2021, 02:22 PM   #5
Moderator Emeritus
 
Comodave's Avatar
 
City: Au Gres, MI
Vessel Name: Black Dog
Vessel Model: Formula 41PC
Join Date: Jul 2015
Posts: 21,131
We have Promariner (3) in our current boat and have used them in previous boats also. Putting in a large inverter/charter can be a fairly involved installation. If all you care about powering is the refer then I would just put in a small dedicated inverter, much easier.
__________________
Boat Nut:
If you are one there is no explanation necessary.
If you aren’t one, there is no explanation possible.
Comodave is offline   Reply With Quote
Old 06-12-2021, 02:55 PM   #6
Guru
 
kthoennes's Avatar
 
City: Sioux Falls, South Dakota
Vessel Name: Xanadu
Vessel Model: Mainship 37 Motor Yacht
Join Date: Oct 2013
Posts: 2,471
Thanks everybody so far. Quick reply on clearance just for the moment, installation specs on the LG say 2" for sides, top and back:

https://images.thdstatic.com/catalog...32dbe6da42.pdf

I'll actually have more than that all around, since the LG is about 2" less in depth than the Norcold that's coming out, and about an inch and a half smaller height and width than the Norcold. There's also 3" of dead (empty) space inside the fridge cabinet on top, and a 16" x 3" ventilation louver in the top of the cabinet, so I'll be able to mount the fan there. I've researched this (way too long) so I think I'm all set. So you can see what I mean here's a photo of our galley -- not our boat, just grabbed it off a sales listing a second ago for convenience, but same make and model, nearly identical. I see these owners did the same thing we have in mind, removed the original Norcold and replaced it with what looks like a residential fridge. I see they also ran matching cherry trim around the edge (Mainship just ran the trim around the top), and we'll probably do the same thing. I have a pile of dark cherry at home in my wood shop.
Attached Thumbnails
p37681w.jpg  
kthoennes is offline   Reply With Quote
Old 06-12-2021, 06:51 PM   #7
TF Site Team
 
koliver's Avatar
 
City: Saltspring Island
Vessel Name: Retreat
Vessel Model: C&L 44
Join Date: Nov 2007
Posts: 5,656
So far no one has mentioned the size of your battery bank. Whenever you are unplugged, your residential reefer will be consuming all of its power through your soon to be new inverter, so your Energy Star rated 220 kw / yr will need to come from the house batteries.

Doing some of the math, 220kw/yr/365=602w/day. Your house batteries will new have to find a new 600 watts every day that you are not plugged in. Those watts, from 12v batteries, 600/12=50 new amp hours, every average day. With inversion losses, say 60, and on hot days, say 100 new amps.

Most Golf cart 6v batteries are rated at 220 amps. If you limit discharge to 50%. that gives you 110 new amps available from a new pair of Golf cart batteries. So you then end up with enough new capacity.

Now you need to know you have the charging capacity to put all those amps back into your house bank, so just buying a new, dedicated inverter to run the fridge is just the beginning.
Fridge
Inverter
Batteries
Higher capacity charger

I know I have over simplified, but when you figure in all the related costs there is a lot more to consider.
__________________
Keith
koliver is offline   Reply With Quote
Old 06-13-2021, 12:50 AM   #8
Guru
 
Jeff F's Avatar
 
City: Guelph
Vessel Name: Escapade
Vessel Model: 50` US Navy Utility trawler conversion
Join Date: Nov 2015
Posts: 2,432
I'm not sure I see the connection between the new fridge and a new battery charger. My guess is that the new fridge will use less power than the old, and when plugged in you will be less reliant on your charger. If it's working good I'd suggest leaving it alone, at least until you're ready for new batteries or it starts acting up.

I'd be really surprised if that new fridge draws more than 500 watts. I ran a home fridge off a 1000w inverter for 10 years on my last boat without issue.
Jeff F is offline   Reply With Quote
Old 06-13-2021, 09:57 AM   #9
Guru
 
tiltrider1's Avatar
 
City: Seattle
Vessel Name: AZZURRA
Vessel Model: Ocean Alexander 54
Join Date: Aug 2017
Posts: 4,281
Since you are switching from a dc fridge to an ac one and you need to add an inverter anyway. Now might be the time to install an inverter/charger. While there are many good choices a Magnum 2000w pure sine wave inverter/charger would be a good choice.
tiltrider1 is offline   Reply With Quote
Old 06-13-2021, 01:06 PM   #10
Guru
 
Xlantic's Avatar
 
City: Mahón, Menorca
Vessel Name: Halcyon
Vessel Model: 1973 Grand Banks 50
Join Date: Mar 2015
Posts: 517
Quote:
Originally Posted by kthoennes View Post
Thanks everybody so far. Quick reply on clearance just for the moment, installation specs on the LG say 2" for sides, top and back:

https://images.thdstatic.com/catalog...32dbe6da42.pdf

I'll actually have more than that all around, since the LG is about 2" less in depth than the Norcold that's coming out, and about an inch and a half smaller height and width than the Norcold. There's also 3" of dead (empty) space inside the fridge cabinet on top, and a 16" x 3" ventilation louver in the top of the cabinet, so I'll be able to mount the fan there. I've researched this (way too long) so I think I'm all set. So you can see what I mean here's a photo of our galley -- not our boat, just grabbed it off a sales listing a second ago for convenience, but same make and model, nearly identical. I see these owners did the same thing we have in mind, removed the original Norcold and replaced it with what looks like a residential fridge. I see they also ran matching cherry trim around the edge (Mainship just ran the trim around the top), and we'll probably do the same thing. I have a pile of dark cherry at home in my wood shop.
The more ventilation the less power it will draw. If you can increase ventilation with vents at the back or the top of the cabinet it would help.
__________________
Gilberto
Xlantic is offline   Reply With Quote
Old 06-13-2021, 05:14 PM   #11
Guru
 
Jeff F's Avatar
 
City: Guelph
Vessel Name: Escapade
Vessel Model: 50` US Navy Utility trawler conversion
Join Date: Nov 2015
Posts: 2,432
A charger/inverter is nice. But if you're paying someone to do it right on an old boat it gets expensive. It's not hard to spend 4k+ on an 2kw install starting from scratch. And after that you start to see the deficiencies in your battery and charging systems. It's a slippery slope.

I did some sleuthing and it sounds like your new fridge won't draw more than about 150 watts.

If the only need is supporting the new fridge a high quality very small inverter is a simple install, even for DIY. A $100 Victron 250w inverter could be hidden behind the fridge and powered from the existing DC breaker and wiring for the old fridge. It doesn't get any simpler than that, and from an overall wiring and power management point of view is completely plug and play.
Jeff F is offline   Reply With Quote
Old 06-14-2021, 06:55 AM   #12
Senior Member
 
MacPhid's Avatar
 
City: N/A
Vessel Name: Late Harvest
Vessel Model: Bayliner 3888
Join Date: Nov 2016
Posts: 147
Keep in mind that most residential refrigerators have automatic defrost cycles using an electric heating element that can be 400 watts or more. Be sure to size the inverter and battery bank with that in mind.

James
MacPhid is offline   Reply With Quote
Old 06-14-2021, 07:51 AM   #13
Guru
 
mvweebles's Avatar
 
City: Saint Petersburg
Vessel Name: Weebles
Vessel Model: 1970 Willard 36 Trawler
Join Date: Mar 2019
Posts: 7,166
Quote:
Originally Posted by Comodave View Post
We have Promariner (3) in our current boat and have used them in previous boats also. Putting in a large inverter/charter can be a fairly involved installation. If all you care about powering is the refer then I would just put in a small dedicated inverter, much easier.
Amen to that. Installing a whole-boat inverter/charger requires heavy cables and switching to isolate the inverter power from shore power. It's a major system upgrade that probably doesn't make sense for just the fridge. Inverters are pretty inexpensive these days. I recently installed a Magnum 3.2kw hybrid inverter/charger that was around $1200 but the install was a LOT more due to cabling, switches, breakers, etc. A simple 1000W inverter can be had for $200 and might even come with short cables. Plug-and-play for a single appliance.

But I do want to encourage the OP to consider replacing the battery charger. These have come a long way in the past 25-years. Modern 3-stage (or 4-stage) chargers will extend the life of your batteries. In addition to coarse chemistry-selection (AGM, FLA, Lithium), some have user-programable settings so you can tweak the charge profile to the OEM's recommendation. For example, a larger bank will need a longer equalization period. Likely very easy to install in under an hour, it's time for a modern battery charger.

Peter
__________________
_______________________________________
Cruising our 1970 Willard 36 trawler from California to Florida
Join our Instagram page @MVWeebles to follow along
mvweebles is offline   Reply With Quote
Old 06-14-2021, 09:44 AM   #14
Guru
 
tiltrider1's Avatar
 
City: Seattle
Vessel Name: AZZURRA
Vessel Model: Ocean Alexander 54
Join Date: Aug 2017
Posts: 4,281
So quick of everyone to discount the consideration of the inverter/charger. No one asked the OP if a system wide inverter would add more utility to the OP. Never mind that an inverter/charger is a 100 amp battery charger. No, let’s just offer up a cheap inefficient hack with out considering the whole picture.

How about we consider the whole picture and then offer up an opinion.
tiltrider1 is offline   Reply With Quote
Old 06-14-2021, 10:09 AM   #15
Guru
 
mvweebles's Avatar
 
City: Saint Petersburg
Vessel Name: Weebles
Vessel Model: 1970 Willard 36 Trawler
Join Date: Mar 2019
Posts: 7,166
Quote:
Originally Posted by tiltrider1 View Post
So quick of everyone to discount the consideration of the inverter/charger. No one asked the OP if a system wide inverter would add more utility to the OP. Never mind that an inverter/charger is a 100 amp battery charger. No, let’s just offer up a cheap inefficient hack with out considering the whole picture.

How about we consider the whole picture and then offer up an opinion.
How about we answer questions and take at face-value the OP's statements? The guy (presumably a guy) didn't want to spend $1500 on a DC/AC fridge, so went with a $500 home-grade appliance that opens the wrong direction and will need some carpentry but was installed in an afternoon (all reasonable decisions). That's the problem he was trying to solve. He didn't ask about powering the Mars Explorer or decorating a Russian Winter Palace. Just how to power his AC fridge. That's it.

A system-wide inverter/charger will need 1/0 cables, transfer switches (more complex if there's a generator), fuses, monitors, etc. $2k-$3k just for parts plus installation. No one ruled it out, just offered balanced advice that if fridge was the main objective, a dedicated 1000w inverter for a few hundred bucks would do the trick. And it will.

Hack or not (and I don't think a dedicated inverter is), I call it the fastest way to cold beer.

Peter
__________________
_______________________________________
Cruising our 1970 Willard 36 trawler from California to Florida
Join our Instagram page @MVWeebles to follow along
mvweebles is offline   Reply With Quote
Old 06-14-2021, 10:48 AM   #16
Guru
 
tiltrider1's Avatar
 
City: Seattle
Vessel Name: AZZURRA
Vessel Model: Ocean Alexander 54
Join Date: Aug 2017
Posts: 4,281
Quote:
Originally Posted by mvweebles View Post
The guy didn't want to spend $1500 on a DC/AC fridge, so went with a $500 home-grade appliance that opens the wrong direction and will need some carpentry but was installed in an afternoon (all reasonable decisions). A system-wide inverter (the Magnum PSW/20002 Inverter/Charger is over $1k alone - no cables) upgrade with 1/0 cables, transfer switches (which might include integrating with generator if his boat has one), fuses, monitors, etc. would take multiple thousands of dollars and take weeks to get all the parts together and install.

Hack or not (and I don't think it is), I call it the fastest way to cold beer.

Peter
I can support this logic. I just see a series of poor decisions being made.
tiltrider1 is offline   Reply With Quote
Old 06-14-2021, 11:02 AM   #17
Guru
 
mvweebles's Avatar
 
City: Saint Petersburg
Vessel Name: Weebles
Vessel Model: 1970 Willard 36 Trawler
Join Date: Mar 2019
Posts: 7,166
Quote:
Originally Posted by tiltrider1 View Post
I can support this logic. I just see a series of poor decisions being made.
In practice, I'm with you Tiltrider. I strongly prefer a solid infrastructure backbone. Provides lots of flexibility and reliability in the long run. But upfront, it's an expensive and time consuming investment.

Personally, I think RV/household style fridges on boats are a poor choice as they are efficient at just one thing: launching contents into the cabin. Left to my own preferences, I would ask "why not just build a hyper-insulated box with remote 12VDC compressor, preferably water-cooled? No inverter needed" Of course, that's even more distance to cold beer.....

Peter
__________________
_______________________________________
Cruising our 1970 Willard 36 trawler from California to Florida
Join our Instagram page @MVWeebles to follow along
mvweebles is offline   Reply With Quote
Old 06-14-2021, 04:17 PM   #18
Guru
 
Jeff F's Avatar
 
City: Guelph
Vessel Name: Escapade
Vessel Model: 50` US Navy Utility trawler conversion
Join Date: Nov 2015
Posts: 2,432
Quote:
Originally Posted by mvweebles View Post
In practice, I'm with you Tiltrider. I strongly prefer a solid infrastructure backbone. Provides lots of flexibility and reliability in the long run. But upfront, it's an expensive and time consuming investment.
Agreed. I have a large charger/inverter and dual voltage fridge on my current boat and spent a lot of time and money on wiring upgrades to support and protect the high DC loads.

Whatever is installed should be properly wired, with appropriate fault protection and wiring size. Accommodating a 20 amp dc device is trivial, but a 200 amp DC load will require some big mods on the OP's existing system. I'm not arguing against that, but realistically it could represent a work package that amounts to 20% or more of the boat's total value and eclipses the economics of the fridge decision.
Jeff F is offline   Reply With Quote
Old 06-14-2021, 06:56 PM   #19
Senior Member
 
Rossland's Avatar
 
City: Buffalo
Vessel Name: Almost Perfect
Vessel Model: Kadey-Krogen 48
Join Date: Dec 2015
Posts: 232
QUOTE=koliver;1011898]

Doing some of the math, 220kw/yr/365=602w/day. Your house batteries will new have to find a new 600 watts every day that you are not plugged in. Those watts, from 12v batteries, 600/12=50 new amp hours, every average day. With inversion losses, say 60, and on hot days, say 100 new amps.
.[/QUOTE]

I think you are confusing watts and amps. 50A/hr/day thru an inverter (modern inverter/chargers such as Victron Multiplus are about 93% efficient) equals about 54AH from a battery. If the battery usable capacity is 400AH ( eg: four 8D AGM or four 100AH lithium), the fridge would be able to operate for a week on a single charge. Of course this doesn't take into consideration all the other loads on the boat Put another way, a 200A battery charger would take less than half an hour to replenish all the energy used by the fridge in a day, and a 150A engine alternator would take about 40 minutes.
Rossland is offline   Reply With Quote
Old 06-15-2021, 06:04 AM   #20
FF
Guru
 
FF's Avatar
 
Join Date: Oct 2007
Posts: 22,553
" Put another way, a 200A battery charger would take less than half an hour to replenish all the energy used by the fridge in a day, and a 150A engine alternator would take about 40 minutes."

This is where numbers and reality chemistry collide.
Perhaps the new auto batts can be charged to 100% with a large charge rate , but it doesn't work for simple LA (lead acid) or even AGM.

Heat in the battery being charged is one problem, that can only be handled by a temperature control for what ever is charging the batt..

The other hassle is the chemistry of most batts , bringing them up to 85% or so can be done with a big charger , but the last 10% or 15% takes a far longer time.

If 100% charge is not reached often, the batt slowly looses capacity.

Many long term cruisers use larger batt banks , to be able to accept this slow death , from the not fully charged condition.

Today solar is a great help in getting that 100% required charge.
FF is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


» Trawler Port Captains
Port Captains are TF volunteers who can serve as local guides or assist with local arrangements and information. Search below to locate Port Captains near your destination. To learn more about this program read here: TF Port Captain Program





All times are GMT -5. The time now is 03:31 AM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012