Adding Refrigeration...

[Loren Beach]

I have been spec-ing out the size and type of components for converting our ice box. I have measured our existing box several times and I calculate it to be (about) 3.0 cu. feet of interior.
I do not know why, but this just seems like "too small" of a number. The tape doesn't lie, though, so it appears that a Frigoboat Model 130F evaporator will do the job. This model is next to their smallest, and rated for a max. capacity of 6 cu.ft. "with good insulation."

Current plan is to install the Frigoboat "keelcooler" option when the boat is hauled for a bottom job this March. I have been advised to go with the version with zincs, as we have no bonding in this boat.
Compressor will be the K50-SSC model with Danfoss BD50 compressor. These use a "smart speed control" and a thermostat. At least that's how I understand it. Parts cost is said to run about $1200., give or take. I will have the yard install the keel cooler and I will do the rest of the installation.
There is room to put all the components under the sink, within a few feet of the side of the icebox.

Anyone with experience with this set-up or similar is invited to comment!

The boat is an '88 Olson 34. We have previously insulated the top and lid, the only parts not insulated by Ericson. We now get about 5 days out of 40# of block ice.
In case anyone wonders... block ice is getting harder to souce every season, after we leave our dock. All we find (everywhere! nowadays) is bags of cube ice.

Besides, I am ready for a change to Modern Times....

Advice anyone? Consent? Derision?


Thanks,
Loren in Portland, OR

 

[u079721]

Hate to see you move away from the simplicity of using ice. We put 10 blocks in our cooler and only top it off about every 8 days. But then we have access to blocks at all of our ports of call in the North Channel. If we couldn't get blocks we would have installed a fridge by now too.

Will you be using this on the hook, or mostly at marinas? I ask because I have had a number of friends install fridges for use on the hook without upgrading their electrical systems to have enough capacity. The factory original charging systems and battery banks on our boats are just not up to the task of 24/7 fridge use. For that you need both larger banks and a higher capacity alternator. All of which explains why I am happy to stay with blocks of ice!

 

[Loren Beach]

Thanks!

Thanks, Steve, for the input.
We will be at anchor for 3 or 4 days at a time. I know that our house bank is marginal for this, but after the upgrade to the two Trojan T-145's (with an added starting/emergency battery), I am out of room for orderly battery expansion in this boat...


So, I have 235 AH of house bank. The original 50 amp alternator was rebuilt and is slated for rotation into the "spares" locker when we go with an unregulated version of this model in the future with a fancy external regulator. Other sailors have done this, and the cost is less than half the Balmar price.
Initially, we will go with the existing battery/charging setup, and see what happens.

There is also room to add another inch of closed cell insulation around most of the factory foam around the existing box, which will help a bit.
I plan to replace the plywood lid with a foam sandwich lid in the future, as well.

Thanks again,

Loren in PDX

 

[rssailor]

Charging your house bank

Charging your batteries with an externally regulated alternator is one of the smartest things you can do. Go for the Balmar MC 612 unit. It is the best on the market and get the optional temp sensors for both battery and alternator. You can program the unit with little effort. Your batteries will get charged better and last longer. Make sure you get a good quaility alternator that is ready to be abused by the MC 612 when charging your house bank. Try not use an alternator any smaller than fifty amps. Twenty percent of your house battery capacity is a good minimum number for the size of your alternator. Also think about using the center fielder unit to charge you engine battery with. It is a great unit and really is one of the few units out there to really charge you engine battery from the house smartly and regulate the current flow between the house and engine banks. Ryan Ryan's Marine Alameda CA