Converting refrigerator from dc to ac/dc

[Jened1840]

How difficult is it to convert refrigerator from 12vdc to 110vac/12vdc. I have a 2007 marlin I run the refrigerator all summer. While at the dock I am plugged in and would rather not have battery charger on 24/7

 

[Viking88rd]

following. Same boat, same dilemma

 

[wspitler]

I'm surprised. My 2007 330 has a fridge that is either AC or DC. Short of replacing with one like mine, you'll need a rectifier with adequate capacity to change AC into DC. Essentially the same as a a battery charger, but dedicated to power the refrigerator via DC. Not too expensive, but make sure the capacity will handle the starting surge of the compressor. You'll also need a switching circuit to isolate the DC feed to the fridge from the rest of the boat's DC system so as not to backfeed the boat. You may be able to find both in one box if you do some research.

 

[Hookup1]

If your are really to determined to have a 12 VDC / 120 VAC automatic switch system you need a 120 VAC DPDT relay and a 120 VAC 12 VDC 10 amp or better power supply. When on shore power the relay is "picked up" and powers the 12 VDC power supply. When no shore power the battery powers the refrigerator.

This is a pet peeve of mine that I want to fix.

 

[Fishtales]

I've had my 2006 Marlin on the dock with the 12v fridge since new. Never had a problem, granted I am not on the hook or somewhere where the fridge is on continuously with out the motor or shore power on. Even if you do this, you'd be running the genny which has its own set of issues (noise, diesel smell etc). I just don't see the need to do it.

 

[PDX-Boats]

I'm open to replacing the fridge on mine. What brand did you get with your Grady that was already AC/DC?

 

[Hookup1]

At the dock my fridge is running off the battery and the battery charger. I would rather it run off AC power. I have been planning to do this for a while. I committed and ordered parts.

If you are OK doing some simple electrical work for $30 you can convert your 12 VDC refrigerator to a 12 VDC/120 VAC automatic switch over when AC power is present. A lot cheaper then a new refrigerator!

The AstroAI AC to DC Converter 8.5A 110 to 12V power supply is $16.99 on Amazon. This is a power cord style similar to the type you see on home electronics. I have AC power behind my refrigerator from when I removed my microwave. You may have an outlet there too.




The DPDT relay is a URBEST JQX-12F 2Z for $11.99 on Amazon. It uses crimp lugs. This can be mounted on the bottom or back of the refrigerator. On my unit it will install on the bottom.



Wiring is simple.
The 12 volt + and - are wired to the relay coil + and - and jumper to the coil normally open contacts.
The boat 12 volt + and - are wired to the normally closed contacts.
The refrigerator + and - are wired to the common contacts.

 

[Legend]

I'm open to replacing the fridge on mine. What brand did you get with your Grady that was already AC/DC?

I replaced my Isothern OEM on a 2004 Sailfish with a new one last year and it came as AC/DC. I had to add an outlet in refigerator cabinet to accomodate the new one. An easy fix since there was an electrical cabin outlet that backed into the the refrigerator cabinet space.
The new Frig was the exact same dimensions and color as the OEM and was AC/DC. It switches to DC 2 minutes after disconnecting from AC.

ISOTHERM Cruise 49 Elegance Black AC/ DC model

 

[wspitler]

I'm open to replacing the fridge on mine. What brand did you get with your Grady that was already AC/DC?

On my 2007 330 the fridge is an Isotherm Cruise 65 model # 1006502 and is AC/DC. Still works good.

 

[dude23455]

do these refrigerators use the Danfoss BD compressor? if so, switching to AC/DC is as simple as changing the compressor controller unit.

I can look up the model number if anyone is interested.

 

[Hookup1]

At the dock my fridge is running off the battery and the battery charger. I would rather it run off AC power. I have been planning to do this for a while. I committed and ordered parts.

If you are OK doing some simple electrical work for $30 you can convert your 12 VDC refrigerator to a 12 VDC/120 VAC automatic switch over when AC power is present. A lot cheaper then a new refrigerator!

The AstroAI AC to DC Converter 8.5A 110 to 12V power supply is $16.99 on Amazon. This is a power cord style similar to the type you see on home electronics. I have AC power behind my refrigerator from when I removed my microwave. You may have an outlet there too.

View attachment 18378


The DPDT relay is a URBEST JQX-12F 2Z for $11.99 on Amazon. It uses crimp lugs. This can be mounted on the bottom or back of the refrigerator. On my unit it will install on the bottom.

View attachment 18379

Wiring is simple.
The 12 volt power supply + and - are wired to the relay coil + and - a jumper to the coil normally open contacts.
The boat 12 volt + and - are wired to the normally closed contacts.
The refrigerator + and - are wired to the common contacts.

Wrapped the conversion up today using the above products. Hardest thing was mounting the power supply. Plugged into old microwave outlet. When 120ACV is present the power supply delivers 12VDC to the relay coil and normally open contacts. No 120VAC relay is open and 12VDC powers the refrigerator.

 

[Fishtales]

Cool. Thanks for sharing and keep us posted on pros/cons as your use unfolds.