12 v refrigeration

[Lady Hawk]

we have a 110 v and 12 v nautic-kold refrigeration system. can anyone help with some basics? our 110 v system works just fine and keeps our box freezer nicely at 20 below. however, when we change over to try to use our 12 v system, it doesn't seem to want to work.

thanks

bruce and dawn

[charleskaluza@gmail.com]

Sounds like the inverter that converts the 12volts is dead.

good luck

Charlie

[Lady Hawk]

thanks charlie

our inverter doesn't supply power to the 110 v side refrigerator. our 110 power derives either from shore power or our gen set. this 12 v refrigerator side has its own motor and compressor supplied from our house bank.

thanks

bruce

[Ex-Calif]

It will be difficult to troubleshoot without a wiring diagram as all we can do at this point is guess.

Have you measured the 12V input at the fridge? i.e. Are you getting 12V into the fridge?

If so the next step is the fridge wiring diagram - is the 12V input fused?

I couldn't find any specs onteh nautic-kold website. Are you sure there is a separate 12V motor and compressor?

If good input 12V, no bad fuse and a separate motor, you gotta start thinking motor...

[Richard Kollmann]

Your refrigerator compressor when connected to 110 volts runs on 24 volts DC. When connected to 12 volts DC compressor's electrical module is powered by 12 volts. If you look at your unit there are two electric boxes the Danfoss electric module mounted on compressor and the other add on boxis a Coolbox MPS Rectifier sometimes referred to as an invertor.

The first item to check is to insure that there is more than 12.5 volts at Danfoss module when AC is turned off, If not the rectifier could be bad or there is a problem with a resistance connection in boat's 12 volt wiring. Many of these units have a troubleshooting LED that will guide you to the problem if your unit is so equipped and the problem is identified at Danfoss module.

[Lady Hawk]

We will work through your suggestions. Here is the kicker. We know the 12volt separate system works but it seems there is a certain combination of "offs" and "ons" that allow the compressor to get the message.

We use the 110 all the time no problem. The breaker for 12volt is sending the signal to a 60 minute timer. The thermostat knows the setting (you can hear it click). I even defrosted the unit to 25 degrees above zero in the freezer side where the expansion valves are located to be sure the valve was not frozen stopping the call for cooling. It all works we just don't know how to trigger the 12 volt side to take over. We have had it running a few weeks ago but we suffer from "sometimers" desease and can't remember how we did it.
Dawn

[Richard Kollmann]

My mistake you do not have a AC/DC Danfoss compressor system so forget my post. It now sounds like there are two seperate systems.

[Lady Hawk]

attn on deck attn on deck

we troubleshot the problem, thanks to dan and richard. we worked thru the elec supply, found no current at the motor, turned on master circuit breaker and voila....
........duh.......... got power and the darn thing's working. thanks to all.

important lesson learned - exhaust all possibilities before you go public

bruce and dawn

[btrayfors]

A TRUE STORY...

Twenty-two years ago I was giving a demonstration in my State Dept. office of a fancy new color pen plotter. It made fantastic color graphs (for its time).

The folks were all gathered 'round the plotter, including the manufacturer's representative.

We couldn't get the damned thing to work. At all. After 10 mins of futzing around with it, I called a data person in another office whom I knew used these fancy new things.

She arrived in about five minutes, a very attractive young lady as well as a very smart one.

She looked around for a few seconds, reached down, and plugged the plotter into the 110V receptacle on the wall. The plotter began to work immediately.

"Hmm", I thought, "this is the kind of lady I ought to keep close by".

We've been together for 22 years now, and she still keeps me outta trouble -- most of the time, anyway :-)

Bill

[Sandero]

Bill,

Oh that's funny. What a darling story!

jef
sv shiva

[Ex-Calif]

This is the absolute truth - The two most common solutions to the help desk are

1/ Did you plug it in.
2/ Did you put batteries in it.

Don't feel bad - It's the forest and trees thingie.

I have often done on-site troubleshooting and often the person will get mad when I go back and start at the begining. You just always have to start at square one.

[migot1]

I have one of those Fridg on board. it will work in the Marina when conected to the shorePower, but at sea on 12V it will not! you need a real BIG battery to run the fridge on 12V. I have a 110 AMP 12V Battery--but it is not enough. one selution is to have a 120Amp new Alternator to recharge the domestic battery...