Need New Fridge - Advise Me, Please

[TOM]

Our Frigaboat keel cooling fridge has somehow got salt water in it,i suspect that the shoe has been hit by something whilst underway {cruising Malaysia and a lot of rubbish in the water} consequently there is salt water in the compressor and most probably in the evaporator plate the whole unit will need to be replaced.I do not want to put in another keel cooler as this would involve hauling out and i'm afraid the same thing may happen again.My choices are .
A- Figaboat BD 50 aircooled ,benefits are easy install and reliability ,negatives are drop in performance some say up to 30% depending on what you read.
B Water cooled unit using seawater or i'm hopeing i could use the freshwater tank [Is this possible?]
C I have looked at the OZE FRIDGE unit which uses BD50 compressor and holding plate,i kind of like this idea as it just seems like a better way to cool a fridge,it is air cooled but can be run using fresh water too. Negatives are i will need to get the unit shiped to Thailand and it is exspensive.
As we will be leaving for Chagos late feb i need to get this sorted and would appreciate any advise on the above or other models.Also can anyone recomend any fridge people in Phuket. We are currently in Singapore but will be leaving for thailand soon.
Happy new year to all at Cruising Forum and thanks for all the great advise during the year.
Our Journey Around The Globe on the Good Ship Byamee

[downunder]

Gary Pacey of Outback marine at Gold Coast, Australia has enormous experience developing refrigeration systems for cruising vessels. He has developed a efficient fridge system for a 35 ft vessel for charter and private usage he is building that is plumbed to a hot water system and heats water without a through hull fitting.
Contact Gary Pacey Contact Info - products and systems for boat, yacht, RV, mobile home, caravan and remote powered sites, Gold Coast (near Southport), Queensland | Outback Marine
Also I notice on the Steve Dashew Logs he recommends using a keel cooler in a tank inside the hull.
http://setsail.com/keel-cooling/
“the bronze keel cooler is bolted through a fiberglass tank lid – you need some form of isolation in whatever you do. Tank liquid is deionized water with antifreeze added to the required temperature. Note that if you do not need cold weather protection leaving the antifreeze out is more efficient.
A tank of about 20 gallons/80 liters is sufficient to handle our freezers and fridge with the boat hauled out. Shape should favor surface area over depth, but in the end depends on your structural system and space between framing.”

[TOM]

Originally Posted by downunder

Gary Pacey of Outback marine at Gold Coast, Australia has enormous experience developing refrigeration systems for cruising vessels. He has developed a efficient fridge system for a 35 ft vessel for charter and private usage he is building that is plumbed to a hot water system and heats water without a through hull fitting.
Contact Gary Pacey Contact Info - products and systems for boat, yacht, RV, mobile home, caravan and remote powered sites, Gold Coast (near Southport), Queensland | Outback Marine
Also I notice on the Steve Dashew Logs he recommends using a keel cooler in a tank inside the hull.
http://setsail.com/keel-cooling/
“the bronze keel cooler is bolted through a fiberglass tank lid – you need some form of isolation in whatever you do. Tank liquid is deionized water with antifreeze added to the required temperature. Note that if you do not need cold weather protection leaving the antifreeze out is more efficient.
A tank of about 20 gallons/80 liters is sufficient to handle our freezers and fridge with the boat hauled out. Shape should favor surface area over depth, but in the end depends on your structural system and space between framing.”

Thanks i will contact Gary and see what he sugests

[Richard Kollmann]

Tom, I maintain a library of several thousand boat refrigeration problems and solutions. There are a number of troubles involving keel cooler condensers but only one unconfirmed problem involved a possible keel cooler damage and it allowed seawater into boat and not water into refrigerant. I have a failed brass block Frigoboat keel cooler on my bench now and it only extends 1 inch below the hull, with wedge shaped ramped ends that should preventing under water damage. Except for the first generation of these coolers where tubing was exposed to seawater no exterior under water impact failures have been confirmed to me on brass block coolers. Failures where water in refrigerant seems to be a problem are on live aboard boats in service five years or more. Stray low voltage is a problem with all water cooled refrigeration condensers. If and when you hall out I would like to have a picture of cooler and if you remove it I would like to test the failed unit to see what caused it to ingest seawater.


Danfoss BD compressors with capillary tube expansion devices require significant pressure difference to allow proper operation. When condenser air or water temperatures or above are below design levels condenser pressure needs to be maintained at artificially high levels especially when ambient condenser air or water temps are low. Many of the European small 12/24 volt boat icebox conversion refrigeration systems perform well with condenser water cooling of 65 to 75 degrees and refrigerant liquid pressure of 115 to 125 psi. If liquid pressure is to low do to excessive condenser cooling it will result in poor performance. If condenser cooling is to warm to maintain design liquid pressure range unit will no longer be energy efficient.

Tom, if you want maintenance free performance and system longevity with Danfoss BD powered condensing units stay with proven all climate air cooled marine grade refrigeration units.

[Hudson Force]

If low amperage efficiency is high on your list I would agree with the air cooled Danfloss compressor units. We've had ours working well for ten years freezing 3 cubic feet and refrigerating 6 cubic feet at 3amps.

[jkleins]

I was also worried about the air cooled units recommended by Sea Frost for our boat but this summer in 100° temps we were very pleased with the energy efficiency of the units and the ease of care/installation and the lack of noise from a water pump has convinced me I was worried unnecessarily. Now I just have to get rid of the extra throughhull. :-)

Jim

[TOM]

Originally Posted by CaptForce

If low amperage efficiency is high on your list I would agree with the air cooled Danfloss compressor units. We've had ours working well for ten years freezing 3 cubic feet and refrigerating 6 cubic feet at 3amps.

I'm very interested in what model ,make of fridge you use .Are you achieving the above by only using one compressor? .I have a well built 6 cubic foot cabinet that has 4 inch insulation i was hoping to split this into a 2cubic foot freezer and a 4 cubic foot fridge.

[TOM]

Richard,

Thanks again for your advice. I have decided to install an air cooled unit for the very reasons you mention .I will probably go for the frigaboat or the cu200 from Waeco. Without putting you on the spot in your opinion in view of what has happened would you recomend i replace the evaporator plate or do you think i could use the existing one?

We are going to haul out in the next few weeks before we leave for Chagos . I will take pics of the keel cooler and try and ascertain what has happened and send them to you. There does appear to be a very small amount of water coming into the boat from around the keel cooler ,but at this stage it is very hard to tell exactely where it is coming from.

[CSY Man]

Highly recommend the "Cool Blue" systems:

Had mine for 10 years and 11,000 hours run time with no issues or maintenance. Super efficient, fridge and feeezer burning from 50 to 70 amp hours per day.

[GordMay]

Originally Posted by Richard Kollmann

Tom, I maintain a library of several thousand boat refrigeration problems and solutions ...
... If and when you hall out I would like to have a picture of cooler and if you remove it I would like to test the failed unit to see what caused it to ingest seawater ...

Stuff like this is only part of why we call Richard the Marine Refrigeration Guru!

[Hudson Force]

Originally Posted by TOM

I'm very interested in what model ,make of fridge you use .Are you achieving the above by only using one compressor? .I have a well built 6 cubic foot cabinet that has 4 inch insulation i was hoping to split this into a 2cubic foot freezer and a 4 cubic foot fridge.

Tom, I'm using the Technautics "Cool Blue" that CSYman recommended a couple posts above. I have a dividing wall between my refrigerated space and the freezer portion that holds the cold plate. This wall has an array of five 1-1/2" holes that I can open or close to maintain temperatures. This is with the single Danfloss compressor that is a component of the "Cool Blue". My current 8.5-9.0 cufic feet was reduced from an 11 cubic foot box that I well insulated using advice from Nigel Caulder's marine refrigeration text. I should add that this is all for my wife's cruising pleasure. Blessed with a vulgar palette, I could do well with warm drinks, canned, rehydrated foods and the fresh vegetables that can last a term hanging.

[SV Demeter]

It would be helpful to know where folks are cruising when they make performance and amp hour consumption comments. Obviously one cruising in higher latts will have an easier time than someone close to the equator. These ambient air and sea temps have a huge impact on system performance. I found with my new to me boat that the refridgeration worked fine in new england when i bought the boat but after sailing home to Annapolis the unit was over charged with freon for the warmer air and water temps. A careful bleed off of the excess under the direction of the esteemed R. Kollmann did the trick and the unit works well again.

[Richard Kollmann]

SV Escape Plan’s, comment on reporting a mobile refrigeration’s daily performance is correct, this energy information is of no value without knowing all operating conditions. Listed below are variable conditions you need to know when evaluating a reported refrigerator’s energy usage:

• Size of refrigerator box or boxes in cubic ft.
• Controlled temperature in each box. Where in box was temperature recorded?
• Manufacturer of refrigeration unit and compressor size.
• Evaporator or plate manufacture with model number and size.
• If the unit has a variable speed compressor what speed was it running at?
• Describe compressor condensing unit installation and how temperature of condenser cooling medium is controlled during this performance test.
• Refrigeration units are designed for maximum performance with standard day 70 temperatures at degree F. If condensing unit is air cooled what was average air temp interring condenser? If water cooled what was raw water temperature?
• Latitude location and date of boat refrigerator when daily energy readings were recorded.
• Approximant amount of insulation and type.
• Was box kept closed on the day performance was recorded?

There are reports on the web where a four cubic ft refrigerator in one case consumed 18 amp-hrs per day and another four cubic refrigerator consumed 90 amp-hrs. Without knowledge of several of the above variables that legitimately determine daily power consumption these figures are of no value.

Changes in condenser cooling medium’s temperature will change balance of refrigerant pressures and refrigerant flow partially on systems with small condensing units. Manufactures of these small Danfoss BD compressor systems have done their best to set refrigerant levels correctly for cruising climate conditions. It is better to adjust condenser cooling medium’s temperature than tampering with refrigerant to achieve best performance.

[Hudson Force]

Originally Posted by SV Escape Plan

It would be helpful to know where folks are cruising when they make performance and amp hour consumption comments........

Excellent point! My posts are with cruising to Maine in the summer and Florida/Bahamas in winter.

[foggysail]

This post may have little value, for what it is worth I will share my Norcold experience. My 40' Silverton came with a 7-7.5 Norcold, the type that uses two compressors; one for the freezer and one for the fridge section. It was NOISY!!! My hearing is challenged but that pig had no problems annoying me whenever it ran........and it ran often.

The high duty cycle did a job on my battery bank forcing me to upgrade my charger even of weekend use. The battery bank consisted of 2 each group 8 huge storage devices that were charged for 4 hours a day using the generator.

Last summer, I found the #$%^ running almost 100% of the time. Checked it to find one of the compressors running hot as was the evaporator. Enough!

I purchased a Summit 8.5CU that has a much larger freezer, so quite that even Wifey with her good ear cannot hear it operate. The box even has a defrost cycle and an interior light. Best of all, It was an almost perfect fit into the space where the Norcold resided. The Norcold's compressors were located on the back of the back of the box, the Summit is on the bottom so the usable depth of the Summit is greater.

OK, the Summit is a 120VAC machine. I installed a 1KW Xantrex sine wave inverter along with a relay that I use for a transfer switch. When on dock or generator power, the fridge is directly powered from either of those sources. When AC is off, the relay switches the fridge to the inverter. I let the inverter run all the time, loaded and unloaded.

I do recommend at least a 1KW inverter only because of the defrost WHICH I HIGHLY RECOMMEND. The defrost cycle only lasts for about 3-4 minutes at about 600W.

I purchased the fridge on line delivered for less than $500. The inverter was about $250. A replacement Norcold from WestMarine was about $1200 PLUS SHIPPING! No defrost, no interior light and noisy.

Just sharing my experience.

Foggy