Story and photos by Capt. Vincent Daniello
Adding big-boat fishbox ice to a small sportfisher.
More and more, outboard-powered fishing boats in the 35- to 40-foot range are equipped like their larger brethren, including crushed ice makers plumbed into fishboxes. Dometic recently scaled down their Eskimo Ice Makers to just a 16-inch cube, making them ideal for small-boat installations. We recently installed a 250-pound-per-day ice maker on my brother’s 35 Contender.
Location is the single biggest consideration, and planning how the ice delivery hose runs from ice maker to fishbox is the overriding factor. “You want just one single high spot between the ice maker and the fishbox,” warns Rich Meister, Vice President of Gulfstream Marine Air in West Palm Beach (firstname.lastname@example.org). “Every time that hose goes up the machine has to strain to force ice up that hill. We’ve replumbed ice-delivery hoses and seen the current drawn by that auger motor drop by two or three amps.”
Secondary considerations for choosing the best spot include both freshwater supply and a convenient location for the seawater pump. When orienting the unit, turn it so the float switch runs fore-and-aft. Otherwise the machine may cycle erratically when the boat rolls on a rough day. Install a shutoff valve on the freshwater supply, too.
Following Meister’s suggestions, we brought the ice hose up about one foot immediately after leaving the machine to gain enough rise for our long downhill run to the fishbox. This also keeps a bit of pressure on the auger—essentially a corkscrew—so it inches the ice out of the machine smoothly.
From there, the ice hose travels 12 feet aft. A 3-inch diameter PVC pipe was easier to mount than many individual tie wraps, carefully marked and mounted with a one-inch drop per foot. The 1¼-inch inside-diameter ice-delivery hose and surrounding insulation is snug but snakes through the 3-inch PVC pipe. “That PVC ensures the hose doesn’t sag over time,” Meister says. “It makes a lot better installation than just tie wraps.”
At the aft end of the pipe we made a sweeping 90-degree bend across a bulkhead, where we increased to a 2-inch-per-foot drop to help ice flow through the bend. Next, a question-mark-shaped bend brought the hose across the top of the generator, through a bulkhead and immediately down into the fishbox. That question mark isn’t ideal, but a steep drop afterward helped by letting melting water flowing from above lubricate ice flow.
The trickiest part of this installation was deciding how to secure the ice hose within the fishbox. Normally a big, mushroom-type through-hull fitting pushes through from the inside of the box, and the hose is clamped outside the fishbox. But on the Contender the box has to come out often to access pumps and equipment. In the end, we cut the mushroom off the plastic through-hull fitting and used a second nut to secure the through-hull’s threaded section inside the fishbox. (See “Making the Connection,” below.)
Ice builds in the box until it reaches a photo cell mounted inside the box. The location of that photo cell—below and to one side of the ice-delivery exit point—is critical to maximize ice production while preventing a blocked ice hose that can damage the machine’s auger. “The installation instructions spell out the location of that photo sensor,” Meister says. “Follow those instructions to the letter.”
Ice should exit close to the center of the box and as high as possible, so it falls in a pyramid. “Every inch higher equates to considerably more ice in the box before the machine turns off,” Meister says.
With the ice-delivery circuit complete, the rest of the job was easy. All wiring connections—just 120-volt AC power in, 120-volt power out to the seawater pump, and the input from the photo sensor in the fishbox—were made inside the electrical box. We didn’t need it, but an optional remote display simply plugs into a “phone jack” inside the control box.
Seawater plumbing follows exactly the requirements of an air conditioner—the pump must be below the waterline, water must flow continuously uphill to the ice maker, and then continuously downhill to the overboard discharge. (See “Making the Connection,” below.) While the ice maker doesn’t create the volume of condensation expected from an air conditioner, it is fitted with a collection pan that requires a drain hose.
The night before a fishing trip, my brother starts the machine. In the morning he has 40 pounds of ice in the box—more than enough for a few fish. If he catches more, the machine makes ten pounds of ice per hour, using 1¼ gallons of fresh water per hour and about 10 amps of power from the generator. Since the boat is docked behind his house, it saves a morning ice run, and it’s great for parties, too.
Making the Connection
The fishbox is just aft of a bulkhead. We cut a 3-inch-diameter hole in the bulkhead and then a 2-inch hole through the fishbox. Reaching through a hatch, one person can slip our modified through-hull fitting through the bulkhead and into the box, and then install the nut on the inside of the box.
To ensure that the holes in the fishbox and bulkhead lined up, we drilled a ¼-inch pilot hole through both using a speed square to ensure the bit was level and straight. Hole saws finished the job.