Thoughts on DC cockpit fridge

Liberty44140

I have an ice maker in the cockpit, but no fridge. Last boat was a 342 that had both so we really miss the fridge outside. Looking at adding a small drawer fridge. Question is, will a DC only fridge outside hurt my batteries? House is two group 31. I liked having the cockpit fridge always on so when I get to the boat, beers are ready and cold. Looks like it will pull 3 amps, 36 watts so not too bad. Thoughts on this from the electrical experts?

Dream_Inn

I think it will be fine.  When you are on shore power, the charger will keep the batteries topped anyhow.  And just like any AC/DC fridge, it'll be on DC when you leave the dock.  You will be well aware of it, so all should be fine.

Liberty44140

Thanks! If you guys had to choose between AC only and DC only, which would you choose? Looks like this drawer fridge that will fit can be ordered in one or the other (not both). Wondering if AC only would be better and I just don't use it the 1-2 times a year I may anchor out. 

Cableguy Greg

If it was me, I would go with the DC only fridge. That way the beer is always cold. 

Aqua_Aura

I would also choose DC as it always is going to be able to be running. 

Dream_Inn

Plus one for DC.  I guess it depends on how you use your boat, but again it won't hurt while you are plugged into shore power as well.

Liberty44140

Thanks gang, appreciate the feedback. Will post back, hopefully the admiral approves funds and this turns in to a project post Fridges range from $500 - $1000 so needed to work out which unit goes in to the proposal. I agree that if DC always on wont hurt anything, DC only is probably best. 

Handymans342

@Liberty44140. You may want to look at the cut off voltage that the fridge stops working. Usually its 10.5 but some manufacturers may be different. Also can you install a 12 volt solar panel some where to feed the batteries?

TonyG13

Liberty44140 said:

hopefully the admiral approves funds and this turns in to a project post

Just tell her it's "essential" LOL

Liberty44140

Thought about the solar panel Handy, that would be an add if we did a major trip but not for the weekenders we are now. 

Absolutely Tony!

Liberty44140

So I’ve found a great deal on an ac only unit. Here is my thought, I can go with this and if I decide that I really should have dc only, I can add a small inverter. 12v panel already has a switch for this. Any issues with that plan? I don’t know much about inverters but @Dream_Inn don’t you use one for your blender? Thanks 

Dream_Inn

Yes, you can use an inverter.  What you'll need to look at is the surge.  36 Watts is nothing and there are really great inverters to handle that, but how large do you need for the turn-on surge.  Inverters are also not as efficient as directly running off of DC, but if you aren't using it often, then you'll be fine.  Look up the specs of what you bought and I may be able to make a recommendation on an inverter. My blender also has a high surge, but it is something that is used for less than a minute at a time, so an inverter was a no-brainer for it.

Liberty44140

Thanks. I ended up picking up a dometic white 20 liter drawer fridge brand new but with a dent on the back (hidden once installed) for $440 delivered. Half price. Will hold 21 12 oz cans It is ac only so step one is getting it installed on ac. I’ve got a few location options on where to put it. I’ll decide during the summer if I need the inverter or not. 

My preferred location is in the bottom step to the left of the ice maker. Power is right there behind the ice maker and it will fit. My concern though is that this is the engine room, step is hollow and open to engine room so I’d need to build a shelf for the fridge to sit on. Thoughts on this location? Too risky that water could get in? Hard top ends right about here. 

aero3113

@Liberty44140 , will there be enough room to open the engine hatch when the fridge is installed? Will there be a handle on the front or will it be flush mounted like the ice maker?

aero3113

What do you think about moving the ice maker up and installing the fridge under it? Or would that not work with the sink?

Liberty44140

Good questions! That seam is not the main hatch, it is an additional hatch that is bolted down and could be opened if I had to remove an engine, but the main hatch with the actuator is inside of the pic so good there. Would totally be open to moving the ice maker up or down, but there is not enough space. The cutout for the drawer fridge is 10” high by 17” wide. 

Handymans342

What is the height of that step?

Liberty44140

It is about 12" Handy. Will be tight but it will fit. To put things in to perspective, the ice maker door is 14" wide. Location would be great, just not sure if it is "wrong" to mount a fridge like this in to the engine room. It will barely be above the engine, engine ends just about there, then a gap, then fuel tank. 

aero3113

If it’s open to the engine compartment shouldn’t it be ignition protected? 

Handymans342

Is there a flange around the drawer?

Handymans342

Heat from the engines may be a concern 

Liberty44140

Aero, Diesel engine rooms don’t require ignition protection. Not even the starters have to be protected. 

Handy I agree on the heat but man it got crazy hot behind the cockpit fridge and ice maker on the 342. I’d pull the trash bin and be shocked how hot it was back there.
on both accounts though, even though I’m diesel I still run the blowers. It’s good for the engines to get fresh air in there while running and to keep heat out
handy It didn’t come with a flange. I could buy one or make one depending on how I mount it 

aero3113

@Liberty44140 I forgot you were diesel!!

Liberty44140

Plan B is under the helm seat. If my boat came from
the factory with a cockpit fridge it would be a drawer fridge in place of that storage door. Having the storage is awesome so I am trying to avoid this.

Plan C is to relocate the sub and put the fridge in that spot but I don’t know yet if I have the depth. The cockpit ac unit is in there. 

Dream_Inn

Under that step looks like the best spot if it can work and not block that hatch either.  It would be convenient, out of the way, and next to the fridge.  Also easy access for maintenance if needed.

Handymans342

@Liberty44140. There has to be some kind of flange to hide the cut edge

Liberty44140

It doesn't come with it, but yes they sell one for this unit. It is Dometic's CD-20 if you want to look it up. I may make one out of starboard so that it is all white, not sure. But yes the cut edges have to be covered. 

Handymans342

See the stainless frame? 

aero3113

@Handymans342 , are you asking about the frame because it will be a bigger footprint if used? It looks like it wouldn’t fit under the step with it.

Handymans342

@aero3113 @Liberty44140. Looks like the whole fridge mounts with that stainless trim

Handymans342

Check that. Looks like it sits on a shelf and the Dometic web site says it’s DC voltage only?