De-Icer Submersion Depth and Mounting Angle

How deep should the unit hang?

A de-icer works by drawing the warmer, denser water off the bottom and moving it to the surface. Where you hang the unit decides how much of that warm water it can reach and how well the flow spreads once it gets to the top.

Start at 4 to 6 feet for a vertical hang. Set slightly shallower if you are running the unit angled. Hung too deep, the rising water loses its energy before it reaches the surface and spreads poorly, which reduces the open area you get.

Keep at least 1 foot of clearance off the bottom. Closer than that and the unit will pull up leaves, sticks, and sediment, which is the most common cause of a clogged intake.

In colder climates, consider going deeper. Kasco notes that when temperatures are severe, moving warm water up matters more than spreading it across the surface, so a deeper set can be the better trade.

Try more than one spot. Kasco's own guidance is to experiment with a few positions rather than assume the first one is right. Docks sit in uneven bottom contours, and a few feet sideways often changes the result more than a few feet down.

Setting the angle

A vertical hang gives you a roughly circular opening. Angling the unit pushes the flow in one direction, which suits a boat slip, a dock face, or a run of shoreline.

On a rope suspension you angle the unit by moving one line, not by adding hardware. Loop that rope around the top circular band and across one to four of the vertical cage wires. Moving it across more wires increases the angle. Kasco does not recommend going past four wires. Once the unit is powered on it swings up to the angle you set and holds it while it runs.

On a pipe mount, the optional Simple Swivel bracket does the same job, letting you rotate the unit to aim the discharge. See mounting methods for kit numbers.

Working around obstructions and current

Anything at the surface, a hull, a float, a piling cluster, will slow or stop the warm water the de-icer is moving. Current does the same thing in a different way, carrying your open water downstream. Kasco publishes several placement rules for this:

• De-ice from the upstream side so the current carries the warm water through your area instead of away from it.
• Place a boat de-icer at or near the bow, angled to push flow toward the stern. A hull is shaped to pass water bow to stern with the least resistance, so that is the direction that works with the boat rather than against it. Protecting a boat fully often takes more than one unit.
• Bring warm water in from deeper water. Angle the unit from the deeper side toward the shallow area you want open.
• Point multiple units the same way. Several de-icers angled in one direction create a current. Aimed at each other they work against themselves.

Tidal and fluctuating water

Where the water level moves, split the difference: set the unit so it sits in shallow water at low tide and deeper water at high tide. If what you are protecting is a boat, tie the de-icer to the boat instead of the dock. The two then rise and fall together and your depth stays where you set it.

Limiting the open area

If you want a smaller ice-free area than the unit naturally opens, Kasco describes using a curtain to block the flow. Drape a canvas tarp in the water, tied off above the waterline and weighted at the bottom so it hangs a few feet down. Folding the tarp in half over a length of chain is an effective way to weight it. Mark the ice-free area regardless of its size.