I am so impressed with the Isotherm water cooled refrigeration holding plate unit in my sailboat! I plumbed it to use fresh water from an extra 50 gallon water tank for cooling. My solar panels easily provide enough energy to run the unit 24 hrs a day, The smart controller regulates the water pump speed and cooling temperature depending on available power. My refrigeration box is always cold, sometimes too cold!
Doesn't the fan extract warm air from the Sea Frost box thereby forcing cool air to come in over the condensing plate? Doesn't make sense for the fan to pull air into the box.
I am not an refrigeration expert but electrician engineer. The different rate of consumption is caused by the modern compressor on the new one, its more efficient electric motor, that is all. And yes you are right about the old unit cooling flow, it must first cool the evap then the compressor. Sorry for my english.
Actually, they are both the same compressor. The reason the Isotherm unit can be more efficient is the control actually varies the RPM of the motor. Also worth noting that the compressor, in BOTH cases,is cooled by the return flow of refrigerant vapor, NOT by airflow. Any airflow over the compressor is meaningless. If you want to verify this for yourself, look at the compressor on any household refrigerator or freezer, there is no fan. Indeed, before the advent of frost-free refrigerators, none of them had any fans at all. Frost-free units have fans to circulate air inside the cabinet, from the freezer section, through the fridge section, and returning to the freezer.
Efficiency is not directly related to current draw but is a component of it. If unit #1 draws 5A and unit #2 draws 2.5A but unit #2 has to work more than twice as long to cool to the same point, then from a AH standpoint unit#1 is more efficient while drawing twice the amperage. It would appear that the new unit is likely more efficient, I am just pointing out that current draw is not the singular indicator of overall efficiency.
I need to replace the refrigeration unit on my J46. How has the isotherm performed? Were you able to cool both the freezer and the refrigerator with one unit?
They have the same motors, they are variable speed, the controler resistor values on the thermostat circuit control the speed. Lower speed is more efficient= less amps. If the system never was opened no air or moisture ever entered if there was any pressure. The charge fittings should have been removed after changing and O ring caps replaced, both rust prevention the valves are not sole seal permanently.
Thought about it more. You can get atmospheric air in a system that is under pressure while running with the vacuum service port cap off. Icing or other blockage in the liquid line or crimped capillary tube. The service port has to develop below 0 for this to happen. Not common, more common is un-evacuated system assemblies.
Should have called ColdEh The two units use a completely different way of controlling the refrigerant flow . The Isotherm uses a Cap tube , the Seafrost uses a CPV , (constant pressure Valve ),
the new digital controller is all very fancy but if your sailing oceans and it breaks down you are stuffed, no fridge, mutch better go with and old fasioned electro mechanical thermostat, power consumption will be no diferent over a 24 hour period. if the thermostat fails just short out c and t terminals and the compressor will op+erate .non stop... switch off at night. cheers
Are you Sure your Air flow direction Idea is correct there Lint on front of the condensing coil so I think you have air Direction wrong. Just my Hypothesis
Thanks J. Not sure at all, I do not claim to be an expert on fridges, just calling it like I saw it! I can report though that since we did the swap, we have had no further issues (knock on wood).
![How Does Boat REFRIGERATION (& A/C) Work? [Capable Cruising Guides]](http://i.ytimg.com/vi/jTKT3w-6Bl0/mqdefault.jpg)
![How Does Boat REFRIGERATION (& A/C) Work? [Capable Cruising Guides]](/img/tr.png)
This science educator is pretty happy about you using hypothesis when do many people would use theory. Well done!
I am so impressed with the Isotherm water cooled refrigeration holding plate unit in my sailboat! I plumbed it to use fresh water from an extra 50 gallon water tank for cooling. My solar panels easily provide enough energy to run the unit 24 hrs a day, The smart controller regulates the water pump speed and cooling temperature depending on available power. My refrigeration box is always cold, sometimes too cold!
Nice! Good call going with the water cooling to the fresh water tank. We thought about that route also and glad to hear it works well!!!!
Doesn't the fan extract warm air from the Sea Frost box thereby forcing cool air to come in over the condensing plate? Doesn't make sense for the fan to pull air into the box.
We aren't 100% sure the direction of the fan, this was our best guess, we could have looked closer at that!
I am not an refrigeration expert but electrician engineer. The different rate of consumption is caused by the modern compressor on the new one, its more efficient electric motor, that is all. And yes you are right about the old unit cooling flow, it must first cool the evap then the compressor. Sorry for my english.
Great info regarding the motor! We didn't even think of that.
Actually, they are both the same compressor. The reason the Isotherm unit can be more efficient is the control actually varies the RPM of the motor.
Also worth noting that the compressor, in BOTH cases,is cooled by the return flow of refrigerant vapor, NOT by airflow. Any airflow over the compressor is meaningless. If you want to verify this for yourself, look at the compressor on any household refrigerator or freezer, there is no fan. Indeed, before the advent of frost-free refrigerators, none of them had any fans at all. Frost-free units have fans to circulate air inside the cabinet, from the freezer section, through the fridge section, and returning to the freezer.
Very informative. Thanks for sharing.
Glad this one made the cut ;-) Cheers!
Efficiency is not directly related to current draw but is a component of it. If unit #1 draws 5A and unit #2 draws 2.5A but unit #2 has to work more than twice as long to cool to the same point, then from a AH standpoint unit#1 is more efficient while drawing twice the amperage. It would appear that the new unit is likely more efficient, I am just pointing out that current draw is not the singular indicator of overall efficiency.
I need to replace the refrigeration unit on my J46. How has the isotherm performed? Were you able to cool both the freezer and the refrigerator with one unit?
Interested in this answer too. Especially for the volume size of 10cuft.
So far so good! We use 2 units, one for the fridge and one for the freezer. We have cold beer and ice!
@@SailingSweetRuca thanks I thought that might be the case. Any other modifications needed to make this work?
@@SailingSweetRuca Would you mind telling us the model/evaporator size of each unit and ~how much volume they are cooling?
Maybe a recap video and performance review after 2 years aboard along with more details is in order?
Any issues with heel angle and running the fridge? Or are they designed around that potential problem?
Great question. The manual claims a working heel angle up to 30 degrees, thats all we know.
They have the same motors, they are variable speed, the controler resistor values on the thermostat circuit control the speed. Lower speed is more efficient= less amps.
If the system never was opened no air or moisture ever entered if there was any pressure. The charge fittings should have been removed after changing and O ring caps replaced, both rust prevention the valves are not sole seal permanently.
Thanks for adding this!
Thought about it more. You can get atmospheric air in a system that is under pressure while running with the vacuum service port cap off. Icing or other blockage in the liquid line or crimped capillary tube. The service port has to develop below 0 for this to happen. Not common, more common is un-evacuated system assemblies.
Should have called ColdEh The two units use a completely different way of controlling the refrigerant flow . The Isotherm uses a Cap tube , the Seafrost uses a CPV , (constant pressure Valve ),
Cool, we haven't heard of ColdEh, we will have to check them out. You are correct on the capillary tube. We have had good luck so far with the change.
the new digital controller is all very fancy but if your sailing oceans and it breaks down you are stuffed, no fridge, mutch better go with and old fasioned electro mechanical thermostat, power consumption will be no diferent over a 24 hour period. if the thermostat fails just short out c and t terminals and the compressor will op+erate
.non stop... switch off at night.
cheers
Great tip on the wire bypass!!!! We do carry two extra standard thermostats as spares, just in case.
and yes the sea frost will be less efficient as the condencer air is pre warmed by the compressor. pipe size will make no diference to performance.
Thats what she said ;-)
Trying to find me one of these old units that someone is tossing to have spare parts.
I do know that my 12v refrigerator works very poorly in hot climates. cool air across the condenser is the key
Is your unit water cooled or air cooled? Thanks.
Awesome info. That’s not a water filter it’s called a filter dryer
:-)
Are you Sure your Air flow direction Idea is correct there Lint on front of the condensing coil so I think you have air Direction wrong. Just my Hypothesis
Thanks J. Not sure at all, I do not claim to be an expert on fridges, just calling it like I saw it! I can report though that since we did the swap, we have had no further issues (knock on wood).
Better off buying a Dometic stand alone.