Whether it's to keep drinks cold, bait fresh or to put the clink in your cocktails, ice serves to greatly enhance the boating experience. Lugging blocks or bags of melting cubes down to the dock is the traditional way of filling the need, but it can become a thing of the past with the installation of an onboard ice maker.

Ice makers used to be large, cumbersome appliances that were only suitable for yachts with lots of galley space, but advances in refrigeration and insulation technologies have resulted in the availability of less expensive compact units, some of which are portable. Even the largest will still fit under a countertop, and others take up no more space than the smallest compact marine refrigerator. Some combine an ice maker with a refrigerator in a compact unit but at the expense of reduced space for drinks and food. Capacities will vary, but most will make more than 20 pounds of ice per day and have internal storage bins that will hold about half of that.

Planning For Installation
Installation can require mechanical, electrical and plumbing modifications to your boat, all of which should be within the capabilities of a well-equipped, do-it-yourself-er, but if you don't fit that description or have qualms about tackling such a task, you should turn the job over to a professional. That doesn't mean you shouldn't be involved in choosing the unit best suited for your boat and the way you use it. On the contrary, you should discuss the selection of ice makers with the installer and be involved in choosing how it's powered, the location and the method of installation to ensure that the results are what you expected.

Location, Location
There are some important considerations when choosing an ice maker for your boat. The first, of course, is location. You must find a space that will not only accommodate the appliance you choose but also provide the necessary ventilation. And be aware that ventilation is needed for ice makers because they produce heat in the process of making ice. They'll drive you out of an enclosed space in a hurry. This may be the reason that many are installed out in the cockpit. Manufacturers such as Sea Freeze get around the problem by offering models that use a remotely mounted condenser (the part that emits the heat), but such models are more expensive to buy and more difficult to install because of the additional refrigerant lines that must be run between the unit and the condenser.

Filtering Issues
The second consideration for all but the portable types is the need for potable water. And in some cases, drainage may be required at the installation site since water from the boat's freshwater system may not be acceptable for consumption without being filtered or purified on its way to the ice maker. (Portable units can be filled with water from a bottle, require no drainage and can be plugged into any appropriate power outlet.) Charcoal-based filters do a good job of getting rid of most odors and pollutants, but the quality of the resulting ice can still be an issue. Regular treatment of the water with chlorine or other additives may be required to get it up to drinking standards. Water supply lines should have shut-off valves and be installed in a manner that allows them to be drained easily for winterization or for maintenance. Drainage lines, where required, should lead overboard if possible.

Power Requirements
The ice maker's power requirements deserve careful consideration in the planning stage. In fact, an ice maker's thirst for continuous power may be the most significant drawback for many boat owners. In the absence of shore power - either to power the unit directly or keep batteries replenished - an ice maker may not be practical unless you're willing to use it on a part-time basis such as only on the weekends, for example, or shutting it off when the boat isn't being used. Some will require more power than others. Lower- power units may not make ice in the same quantities as ones that use more power. Most ice makers require 115-volt AC (VAC) power. At least one is available to run on 240 VAC, and some are dual-voltage units, capable of running on either 115-VAC or 12-volt DC (VDC) power. Supplying AC power requires almost no extraordinary measures except to ensure that the unit is connected to a line with a dedicated fuse or circuit breaker. Most compressor-driven units can require a surge of power on start-up that's up to five times higher than operating power. This could trip the breaker or blow the fuse if another device is drawing power from it at the same time.

Units that run on AC will require either shore power, the constant operation of an onboard generator or the use of an inverter to change DC battery power to AC. Using an inverter for extended periods of time can drain batteries quickly, so that option should be considered only after a careful review of the boat's DC electrical system - almost certainly a job for a professional. For example, to run an ice maker that requires 300 watts of AC power, the inverter would draw nearly 30 amps of continuous 12-volt DC power and potentially much more at start-up, requiring a robust inverter and high-capacity DC wiring.  The models that operate directly from 12-volt DC can be hard on batteries, too. Even a small unit that requires only 200 watts of power will draw more than 16 amps operating at 12-volt DC, so they'll require heavier-than-normal wire sizes to be used to accommodate the current draw. The manufacturer's installation instructions regarding wire size, circuit breaker or fuse ratings should be followed to the letter to avoid power loss, overheating and the potential for creating a fire hazard.

Final Tips
Unless your needs can be met by a small portable unit, the choice and installation of an ice maker will require careful consideration of all of the aspects of the project to ensure that you get the maximum benefits from it. Look carefully at the manufacturer's warranty and the construction of the unit. An ice maker that was designed for the relatively benign surroundings of a road-going RV may not have what it takes to last in the damp, salty marine environment. One that was specifically designed for marine use may be a better long-term deal, even if its initial cost is somewhat higher. The accompanying list of ice makers (see table on page 71) is by no means complete, but it will give you some idea of the range that's currently available.


QUICK TIPS
1. Choose a location on board that will provide the necessary ventilation.
2. Make sure the water supply lines have shut-off valves and can be drained easily for maintenance.   
3. Consider the ice maker's power requirements.
4. Examine the manufacturer's warranty and the unit's construction.
5. Follow the instructions explicitly to avoid power loss or a fire hazard.