Anyone have this drawer fridge?

[jaysweet]

Any updates on your progress? Looking to add some project for the off season and wondering if this should be on the list.

Thanks!

Actually, yeah. I’ve been meaning to post an update. At the moment, I’m on the last night out of a week-long cruise with the new fridge.

My first observation is that it draws 2.5 amps *while it’s running*. Of course, it cycles on and off, so that’s not continuous draw. In mid-August, I left it on full (coldest setting) for 23 hours, and it took the new 230 AH bank down to 82% state of charge (SOC). Not too bad. So it used 41 AH in 23 hours at coldest setting, and I have 115 AH to “spend”, allowing 50% SOC.

On the first night of my current trip, I had the fridge fully stocked (with cold food). I anchored out after unfortunately motoring the whole way. With normal non-LED light usage, when I woke up the next morning, the batteries were at 93% SOC. Didn’t use the anchor light, which is also non-LED. I did have a small digital thermometer in the fridge, so I had turned it up (warmer), and when I woke up, it said 27 degrees, although nothing was actually frozen in there. So with temps in the boat of maybe (?) 60 overnight, it only used 16 AH. I haven’t done the cooling fans, and for now, I don’t see the need.

The second night at anchor, with the anchor light on, it took the batt down to 90% SOC. This was from 100%, as we were plugged in at marinas in between. Here the rub, though. After the next night at anchor (2 in a row), they were at 75%. The point is that even though I motored for many hours, it’s really hard to get that last 10% or so into the batteries. If you’re plugging into shore power, no problem. If you’re sailing or even motoring for 6 hours, it’s not enough. Tonight, when I set the anchor after 6+ hours of motoring, they were only at 87%.

So I’m very happy with the fridge, but I still think I need solar panels if I’m not going to be in a marina every night. The big issue is the absorption phase, which takes way too long to get the last 10% back into the batteries.

 

[jdrutten]

Nice data gathering! I'd be interested in knowing a bit more about your battery setup. Can I assume you have a battery monitor installed to gather data? My H306 has a pair of group 24 batteries under the aft starboard settee that come to a paltry 150Ah when new (probably more like 120Ah or less now). 230Ah would be great but it doesn't seem like they would fit. Did you happen to use the forward starboard settee or maybe even the port settee? My boat lists a couple degrees to starboard and I've been thinking of trying to move the batteries to the port settee with the refrigerator compressor.

Are you also continuing to use the chest/counter fridge or have you repurposed that space?

 

[jaysweet]

Thanks JD. Our boat came with a group 24 deep cycle for the starter (in the aft starbd. settee) and a group 27 for the house bank (in the forward starbd. settee). The “house“ battery was never really big enough, and I didn’t have a battery monitor, which contributed to my killing a brand new battery in 2020 on a trip in which I was able to sail multiple days in a row with little engine use.

So this past May, I replaced the gp. 27 with a pair of 230 Ah 6 volt batteries. They both fit in the forward stbd settee, oriented side to side, which is supposed to be better.

At the same time, I put in a Balmar SG200 monitor. You can see the shunt in the picture above. This was really not a hard project, although it did take a lot of planning and reading. It was waaay easier than the fridge install.

I did consider putting them on the port side, but I was too lazy. We also put food over there, and I didn’t want a battery and its fumes in the same compartment with the food. I kept the ice box as an ice box, which is needed for multiple days and 4 people, for example.

BTW: it looks like you, me, and Arbee ( in Australia) in this forum all have 306’s made in 2004.

 

[Ralph Johnstone]

The big issue is the absorption phase, which takes way too long to get the last 10% back into the batteries.

If you have an external alternator regulator, it will charge your batteries to 100% SOC much faster, the same as your shore power charger.

Prior to installing the alt. regulator, the charging output never exceeded 10A.

 

[jaysweet]

If you have an external alternator regulator, it will charge your batteries to 100% SOC much faster, the same as your shore power charger.

Prior to installing the alt. regulator, the charging output never exceeded 10A.

Yep: the "next step" is either solar panels, a new alternator, or just a new regulator. I'm leaning towards solar, although which is better seems to depend on usage. "I want to be able to sail for days on end with no motor", may be unrealistic, but tends to indicate solar.

 

[berner73]

Jay, great update and thanks for taking the time to share all the details. The metrics are very much appreciated.

Our house banks are similar to yours but split as 1/2. On a mooring with a small array for trickle charging - don't believe it would keep up with the amperage draw continuously so your data is very helpful. Looking forward to your feedback moving forward.

 

[jaysweet]

Jay, great update and thanks for taking the time to share all the details. The metrics are very much appreciated.

Our house banks are similar to yours but split as 1/2. On a mooring with a small array for trickle charging - don't believe it would keep up with the amperage draw continuously so your data is very helpful. Looking forward to your feedback moving forward.

You're quite welcome. I did a lot of thinking and reading about regular flooded lead acid versus fancier gel cells, fireflies (which aren't available anyway), AGM, LifePo, etc, and decided that for my usage (a handful of overnights plus a longer trip or two per year), it seems clear that standard cheap flooded LA was by far the best bang for the buck.

I strongly recommend a battery monitor, which I had been lusting after for many years. Without one, you're just killing batteries and guessing about your true electric draw. With a monitor, you can turn on just the anchor light (e.g.), and see how much it really draws.

 

[Ralph Johnstone]

With a monitor, you can turn on just the anchor light (e.g.), and see how much it really draws.

I saw 1.0A with tungsten and 0.1A with LED. That's about 6 amp hrs. for tungsten and 0.6 amp hrs. for LED each night at anchor. Well worth it for the savings in battery amp hours . Everything in the boat is now LED.

 

[Ralph Johnstone]

Our house banks are similar to yours but split as 1/2.

Do you mean to say you have two separate house banks and one starter battery.

 

[Captain Larry-DH]

If located in the NE or NW you’re going to need about 300w (rated) of solar to be able to leave the fridge on full time off-grid. Even with that, I suggest you keep the fridge on a Low Voltage Disconnect circuit to save your house bank in event of prolonged cloudy weather. The LVD device should be set to 11.9v (roughly 40% SOC). The standard fridge comes with LVD at about 11.1 which is too late - resulting a dead flat damaged battery.

 

[jdrutten]

...
So this past May, I replaced the gp. 27 with a pair of 230 Ah 6 volt batteries. They both fit in the forward stbd settee, oriented side to side, which is supposed to be better.

Beautiful! I'm officially jealous.

...
BTW: it looks like you, me, and Arbee ( in Australia) in this forum all have 306’s made in 2004.

Yes, so don't be surprised when you find me stalking your posts about anchor locker leaks, engine mounts, or fridge/battery projects!