Adding 12 volt compressor system

[R. Reid Cameron]

We have a 1991 Hunter 43 with engine driven refrig. and would like to add a 12 volt system so we could leave the boat for 1 or 2 days and not loose all our food. I think we sould be able to tie into the liquid to the regulating valve and the vapor out of the cold pack with a small unit. For this type application would you recommend water or air for condensing as the boat is in the Caribbean. Anything I should watch for as it is installed? Thanks for your help.Reid Cameron; Changes in Latitude. reidcam@planet.eon.net

 

[Bill Thomas]

12VDC addition

It is possible to add a 12 volt unit to this system if it has dual circuit plates. Dual circuit plates will have two extra fittings that are not used or are being used as a crossover to utilze the extra tubing for faster pulldown. You cannot use a small danfoss based condensing unit for the 12 volt side as there is not enough capacity in the compressor. Your best choice would be a 1/2 horsepower unit such as the Crosby V-12. This is a water cooled unit and is ideal for Carribean use. Another option, if you have room in the icebox is to add a ColdMachine with the PowerPlate. This would be a stand alone system and would afford redundency should the engine driven unit ever fail.

 

[R. Reid Cameron]

Thanks for your help.

The boat has a plate in the freezer and a seperate one in the frig which are hooked up in series with the control sensing the vapor from the frig plate. Would you use a temperature senser in the frig and/ or the freezer and a timer to limit run time to some number of minutes (30) to prevent damage if the system lost freon? take care. Reid Cameron.

 

[Bill Thomas]

Re: Thanks

First you need to determine if there is an extra set of fittings on the plates. If not, an additional system cannot be added. There, ideally, should be a thermostat for each box to allow better control. If there is just the one thermostat, the tx valve should be on the freezer plate with the sensing bulb on the fridge plate outlet. A timer can be added in the circuit to limit the runtime. In the old bygone days of engine drives, this was often the only method of control.