Isotherm Fridge and water heater

[kcrompton]

I have been looking around at refridgerators and water heaters. I found some called Isotherm that I like and they have a good price. What are peoples experiance with these? Another thing what do people say about cold plate vs actual fridge? And what are good water heaters IYHO? Enigine, electric, gas what do you folks like/use? Any comments related to this would be of much help. I have always sail smaller non-system laiden boats but now want to go cruising and am trying to learn about all these systems.

Ken

[Talbot]

The choice of holding plate versus evaporator is really a choice on how you power your fridge/freezer. If you have sufficient generating power from solar/wind then the evaporator is the more efficient way to go. If you need to run the engine to provide the power, then a holding plate is the answer.

I use gas for water heating (with a Rinnai heater) - very good it is too. However it is a multihull solution only. some people use a calorifier, which takes heat from the engine and keeps it in an insulated tank intil required - this will even work with a salt water powered system (but obviously you need to run the engine). Some people add an immersion element to this calorifier so that it can be run from a shore supply. Eberspacher (ESPAR in USA) have a diesel fired calorifier which will heat water, and this can be used for heating the boat as well as providing hot water. Rumour has it that a new version of this is being developed which will allow shore power to provide the heating for this sytem to save running the diesel heater.

[sv_makai]

We have the Isotherm water heater onboard. It uses the engine or shore power to heat the water. It works very well and the water stays hot for about 3 days.

The caution is that most boats do no use a mixing valve and the water coming out of the fawcet is engine temp 140-170 degrees.

We are sailing in the caribbean and find that the hot water is great but after many days at anchor it cools, but we don't usually reheat as showering in the cooler water is great. If you will be sailing in an area where it is cooler or really want hot water all of the time you will have to run a generator or your main engine to keep it hot.

[kcrompton]

Thanks for the Info. Everyone on these site's (cruiser site's) are so helpful. These opinions help a lot and I am looking forward to reading what other people have to say.

Ken

[Jentine]

One factor that is ofter neglected when determining the type of refrigeration power is the cost of replacing the engine (for a cold plate system) sooner due to the excessive hours used to generate cold. The engine must be run for up to 3-4 hours extra per day to keep the fridge and freezer at temp. Cruisers spend more time on the hook than motoring.
A typical marine auxillary will rot out before it burns out except when an additional 1200 hours a year is added strictly for refrigeration. Addition of solar panels is a one time expendature and most are warranteed for up to 25 years against failure.
I would rather spend $1800 for a few collectors now than $10,000 for a new engine. When all the costs are included in the price, cold plate refrigerators are too expensive.

Have a very Merry Christmas and a Joyous New Year.

[sv_makai]

Makai uses 2 adler-barbar 12 volt cold plates. One for the fridge and a seperate one freezer. We like the cold plates as the are run by 12 volts and with the solar and house bank we have no problems maintaing below freezing temps. the total consumption is about 75amps a day.

The biggest issue we found with cold plates is cleaning the ice build up off them about every 6 weeks or so. AS the ice builds up we see a reduced abilty to keep the freezer cold.

Our solar panels keep up without any problems and are not required to run our engines just to charge the battery bank.