which fridge 4 liveaboard

ribrage

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I have to replace the fridge on my boat and want advice on make and model so as not to buy the wrong thing its for live aboard 50 ft ketch.
It needs to be VERY economic on power consumption as survive on two solar panels and one wind generator cabinet size not essential but around 30 inches by twenty.

I have both 12v and 24 v systems and also 240v generator when needed

what makes would you recommend and why? all advice gratefully received
 
Try Frigoboat water cooled. Good in all climates doubles as fridge and freezer, not the cheapest but not power hungry and very reliable. They (The plates) come in all shapes and sizes.
 
Frigoboat, with engine driven compressor. Has kept us in cold stuff for the last 15 years! Run the engine for 30-40 mins per day and that is sufficient to keep everything cold.
If we were redoing the system today I would add the switch over option that will enable you to use electricity when it is available ie in a marina.
Most of the problems we see in the Tropics are from boats trying to run refrigerators on just solar or wind power. They can do it but it knackers their batteries. Typically needing replacing every 2 years. Our last battery bank lasted 7 years and the current batch are now in to their 5th year and going strong!
 
hmm 2 votes for Frigoboat. i already have a large freezer chest in a locker but the batteries wont run it for longer than 30 mins so I run the engine for a spell each day.
would they be at the southampton boatshow in any form do you know
 
Frigoboat are very likely to be at sibs.

They have several different types of system and the best one will depend on what you have on your boat, ie
the size of fridge
what type of electricity recharge you use
typical daily use
where you will be using the boat (for typical daily air or water temperatures.

There two ways to operate a fridge system:

1. continual use of the fridge system powered from the batteries and run in accordance with the thermostat in the fridge. This is best if you have sufficient wind and/or solar energy to be able to maintain the battery charge, or if you are permanently connected to a shore power cable.

2. bursts of power from the boat's engine to power a major chilling and storage of cold via a holding plate. suitable if you need to run the engine every day to charge the battery.

Having decided the type of system to transfer cold into the fridge/freezer, you need to decide how to cool the system. There are three ways to do this,

1. the simplist is an air cooler - basically a fan driven system, but although the simplist, it relies on the air being sufficiently cold to do the business, possible in a deep bilged boat, or in UK waters in winter, but not in a lot of todays AWBs especially in the med, and of course the electric fan uses a significant amount of additional power (all systems have a pump that shifts the coolant gas around through the cooling plates).

2. the second system relies on pumping water either from an open hull connection, or water that circulates through a pipe attached to the bottom of the boat, this water is then used to cool the condensate in a similar manner to the air fan in the previous example. The open hull fitting is simpler, but suffers from blocking by crustaceans etc. The pipe attached to the bottom does not have that problem, but is rather more vulnerable to damage. Both suffer from the need for an additional pump to pump up the water.

3. A newer variety uses a keel cooler, this is a chunk of bronze that is fitted rather like a through hull sitting. The chunk of metal acts as a heat sink and the condensate piping is run through it, thus needing longer condensate pipework, but no additional pumps. Thus it is the most efficient system, but also the most expensive.

Armed with this knowledge, you should be able to have a meaningfull discussion with the fridge people especially as as far as I am aware, all boat fridges make use of the same condensate pump manufacturer (Danfoss)
 
Dear T, You seem very skilled in things fridgy. I have major doubts about variations in fridge temperature, re stored perishable food - cold chain, and all that - was the raw chicken transported quickly from shop to fridge, and kept constantly cold? Popeye doesn't give a monkey's as long as he has cold beer. Does the holding plate suggestion keep the perishables from perishing, or just keep the beer cool?
 
As you have a generator you don't need to mess about with boaty stuff that usually doesn't last long, because it's designed for weekend sailors, and eats batteries.

Get an industrial grade 240v fridge, we have a Grunert. If you go that route consider an industrial grade water maker and a 240v battery charger, if you don't have one.
 
IMHO the length of time that the cold plate system will work depends on four things:

ambient external temperature
thickness of insulation
number of times you open the fridge (very important if a front opener)
number of items placed in the fridge that are above the fridge temperature.

Throwing a case of beer into the fridge and expecting it to cope without giving it some assistance is a recipe for temperature change in the fridge sufficient to start the bacteria working

Even an evaporator plate system will have problems under these circumstances, but will cope better with a constantly opening fridge door.

Thus you need to understand the performance of your fridge and what happens when you put warm food into it. If you are throwing a case of beer in, either get a cold one to start with, or add a bag of ice at the same time.

An essential item for any fridge used to keep food for reasonable periods is a max and min thermometer.

Packing the food immediately into vacuum packs will make a significant difference to length of safe keeping.

Hope that helps
 
I'm with you on this one, I have industrial/domestic fridge and freezer, run it with inverter and have a 4.0 kw deisel genny I run for 3 hours every two/three days, to charge a 440ah 24v battery bank and when I also make water and wash etc etc. I also have a 180w @24v solar array, which almost keeps up with the drain between charging. Depends how many times I open the fridge, dont open the freezer, unless genny is running! Eats battery power if you do!
A bit of intelligent planning and you can live very comfortably.
I also agree insulation makes a big difference and buying Catagerory "A" appliances also helps. You can always apply more insulation around your fridge to help and keep it out of the direct sun, lots dont! I hang a towel a foot in front of one of mine, as the sun goes down it shines on the door..
 
I think that the answer to this is depends upon where you intend to cruise and how long you are going to be away from shore. The generator or invertor based options are OK but you'll need diesel or shore power to make this work for prolonged periods IMO. If, like us, you spend most of your time at sea or at anchor then as Talbot says holding plate solutions are really the most energy effieicent and least drain on batteries or fuel tank

We have an Isotherm plate system that sits inside our custom built fridge/freezer area. In the Tropics, we can keep all of the box, which has 4-6" insulation and is about 1 cu metre, cold with a couple of 65w solar panels when at anchor indefinitely. The Isotherm plate system which runs off 12v, comes with a power sensor that puts the plate onto overdrive when the batteries are being charged either through shore power or engine. Ours is water cooled but later models are plate cooled. We have a domestic battery bank of 220ah.

Oh, I forgot to say that items near the plate freeze, so we have ice for the rum & coke....
 
we use an Isotherm 195 24v fridge freezer with a 240v auto switching unit. The compressor is very quiet and the isulation around the fridge is excellent. The fridge has an automatic cut off at low voltage and I have been surprised at how efficient it runs.

Compressor probably runs once an hour as it goes on and off with the thermostat and draws only 1/2 an amp on standby, about 4amps when running for a few minutes every hour. One thing I notice is that it is far more efficient than our previous fridge which was about 15 yrs old.

Depending on your individual setup, a water-based cooling may be something to consider as already suggested, but since you have a generator, (and I take it a battery charger) then it won't matter what you go for.

If you have a generator then simply using your battery charger every couple of days isn't going to be a problem. You should find out :

1. Size of battery bank
2. Average ampage per day that your solar panels provide
3. Average ampage per day that your wind generator provides.
4. average amps used per day.

Armed with these things, you can consider if installing a water based system is going to be of any benefit.
 
How many people actually KNOW the temperature of their refrigerator?

I have noticed that those who say that their system works fine have no way of knowing if their fridge is below 5C or not.

Ours has a themometer fitted and if we do all the right things like buying pre-chilled cans and foodstuffs, our two 55watt solar panels just about keep it at 0-5c for most of the time. We have an air cooled (drawn from the bilges) compressor unit (Waeco) running their supposedly most effective evaporator. This one:-

VD15Evap.jpg


but we need to take the cover off of it every three days to defrost it's matrix otherwise the air cannot be blown through it by the fan and the temperature inside the cabinet rises. To avoid the food heating up I use a hair dryer running from our 2000watt inverter for this purpose lining up a row of water bottles inside the fridge to form a thermal barrier, catching the run-off in a purpose made plastics box. I guess that if we didn't have the thermometer we would just go along blithely assuming that all was Ok and that we were out of risk of contracting salmonella!

Steve Cronin
 
Re: How many people actually KNOW the temperature of their refrigerator?

Ahem, Steve it never pays to speculate, we have a calibrated thermometer in the fridge...
 
Re: How many people actually KNOW the temperature of their refrigerator?

OK so you're "ONE" What about the rest?

Do you have an external readout on your home fridge too? We do and it is surprising how long it can take for the temp to recover after a lengthy period of door opening

Steve cronin
 
Re: How many people actually KNOW the temperature of their refrigerato

We have a small fridge run on an Isotherm unit with water cooling using the seacock on the galley sink drain. We have a 50watt solar panel, and mostly, here in Spain, the panel keeps up with our power needs at anchor, although we do have the smallest wind generator too which trickle charges the engine battery. We also keep an eye on things with our Adverc monitor.

We too have an external read out of temperature. We use the outside thermometer from a small weather station which is kept in the fridge and is a cheap way to achieve this with no wiring necessary.

We have been very pleased with the Isotherm, we made our own cabinet, and have a small "ice box" which we made more efficient by fitting a door to the front. Ice for the drinks in no time at all - great. Power consumption about the same as the post above.
 
Re: How many people actually KNOW the temperature of their refrigerator?

Well, Steve to be honest I'm not too concerned about salmonella. Providing that you don't do dumb stuff like mixing cooked and fresh meats and that you cook stuff properly salmonella shouldn't be a prob.

That's consigned me to dose then /forums/images/graemlins/smile.gif
 
Re: How many people actually KNOW the temperature of their refrigerator?

Yeah, we have an internal thermometer with our isotherm hooked to the front rail so as soon as I open the fridge I can see the temp which sits around 4degrees, sometimes it's too cold on the lower shelves for salads. Freezer sits at -18.

As far as maintenance goes, since we use the boat at weekends (not liveaboard apart from 3 weeks a year) we do nothing more than wipe it to clean off the mildew due to having the fridge off midweek.
 
thanks all have printed off your comments and thus armed will fight my way through the crowds to frigo boat at the southampton boat show.

so back to mine for a <span style="color:blue"> </span> cold beer soon ... /forums/images/graemlins/smirk.gif thanks
 
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