5 Ways to Heat Your Boat

November 10, 2014


5 Ways to Heat Your Boat

5 Ways to Heat Your Boat


5 Ways to Heat Your Boat

Cooling temperatures can keep you off the water, but adding a cabin heater can warm your cabin and heat up your next boat party. There are many ways of heating your boat, lets explore some of the more popular methods of staying warm that can keep you on the water all winter long.

1. AC Heaters

One of the simplest methods is to use an AC electric heater plugged into the boat’s AC electrical system. Many models are available, but heaters designed for a marine environment are usually preferable. Electric heaters designed for the marine market are usually made of stainless steel and/or other materials that resist the corrosive marine environment. They should have some sort of safety switch that will turn off the heater if it is tipped over. Some models are ignition protected, meaning that they are safe in gas-powered boat engine rooms. Models without ignition protection certification should not be used in areas where gasoline fumes are present, for obvious reasons. Electric heaters are best suited to boats that either have an AC generator or are usually at the dock where shore power is available. It is not practical to run an electric heater through your inverter, as it will draw the battery bank down too quickly.

2. Fuel Burning Heaters

Fuel burning heaters are among the most popular. Diesel heaters are commonly used with boats that use diesel fuel for propulsion engines as they have a ready source of fuel for the stove. They are available as bulkhead mount as well as floor mount, and may or may not have a fan to circulate the warmed air. All require a flue (stovepipe) that exits the cabin of your boat to dispose of the exhaust. Some heaters use natural convective draft, while others use fan-assisted draft to assist the removal of the toxic exhaust. Some of these heaters have a window, which allows you to enjoy the sight of the burning fire inside the stove. Propane (LPG) space heaters are available with “direct-vent” through fitting and flue cap, where the combustion process is completely isolated from the inside of the boat. Some of the better designs have an oxygen sensor, which will shut off the fuel supply if the oxygen in the cabin reaches a dangerously low level. A few solid fuel heaters burn charcoal briquettes or wood. These also require a ducted flue or stovepipe, as well as a source of wood or charcoal. In the past, coal was used, but modern solid fuel heaters are not designed for coal burning, as it burns too hot.

3. Hydronic Heat

Heated water can be circulated by a pump through tubes or hoses running through the boat to small radiators (heat exchangers) located in the cabin areas that require heating. The heat from the water is transferred to the air by small fans blowing through the heat exchangers, thus heating the boat. These fans can be thermostatically operated, so you can have separate zones of heating, allowing different levels of heat in the individual cabins. The source of the heated water can be from your main engine cooling system, heating coils installed in diesel or propane stoves or ranges, or it can come from your domestic water heater via heat exchangers installed in the water heater. Most marine water heater manufacturers offer optional heat exchanger loops in the water heater, allowing you to heat your galley and head domestic water from the engine, or the heating of water for space heating with the above-mentioned fans/heat exchangers. Multiple zones also are a feature of this type of heating, but add to the complexity and cost of the system. An added benefit is that the bilges, lockers and stowage areas that the hose or tubing runs through will be warmed and de-humidified, decreasing mold and odors common in the colder months.

Hydronic furnaces, which use diesel or kerosene fuel to heat water that is pumped throughout the boat in the same manner as the engine/water heater/radiator system described above. These heaters usually require less maintenance than the forced air furnaces, as the thermal cycling is not as extreme. These types of heaters have a delay between the starting of the heater and when you begin feeling the warming of the cabin, because the water takes some time to heat and circulate out to the heat exchangers and fan that will be warming the air. This hydronic method has many optional ways of connecting to other components, allowing the furnace to serve multiple heating purposes.

4. Forced Air Furnaces

There are several makes and models of forced air furnaces available. These heaters burn diesel or kerosene fuel, exhaust fumes are ducted overboard, and the heated air forced through ducts installed in the boat to distribute the heat. These require rather large ducting in the boat from the heater to the areas of the boat that require the heat. You will feel nearly immediate heat output once the furnace is started.

5. Head South

One other method should be mentioned, and that is to point the boat south, and keep going until it gets warm enough to sit on the deck in your swim suit. If you live in the cold northern climes you may even get a few extra willing crew members to come along for the voyage.

Whatever way you go, keeping your cabin cozy can keep you out on the water even when it’s cold outside.  Even the most thin-skinned companions may be persuaded to go out with a toasty heater onboard.

“Green” Anodes

February 14, 2013

pencil anode

Navalloy Pencil Anode

We use sacrificial anodes on our boats to lessen the electro-chemical reaction between the submerged metal of our boats and the water in which it is used. The difference in electrical potential exists between any two different metals submerged in an electrolyte. For boats, this electrolyte is fresh, brackish, or salt water. This electrical potential is similar to that of a battery, in that there is an electrical current that passes through the water from one terminal to another, or in our case, one metallic material to a different metallic material

An anode is the negative “terminal” and the other metals are the cathodes, or positive “terminal.” The anode is sacrificial because the anode slowly corrodes and dissolves in water, preventing the cathode from corroding and dissolving. Since the sacrificial anodes eventually disappear, they have to be replaced at regular intervals.

Traditionally the sacrificial anode was made of high purity zinc, which does a good job of protecting most of the submerged metals of boats. However, zinc is highly toxic, even in very small quantities, and all of the boat zincs dissolving in our lakes, rivers, estuaries and oceans has a significant effect on the natural environment. Zinc is highly toxic to plants, invertebrates, and vertebrate fish. It is also known to be toxic when inhaled during welding or soldering of galvanized metals, causing “zinc shakes,” “zinc chills,” “galvie flu” or “metal dust fever.”

Other materials traditionally used for sacrificial anodes are magnesium and aluminum. Magnesium has been used for boats located in fresh water, but should not be used on aluminum boats in salt water, as it will cause excessive voltage differences that can cause hydrogen bubbles to form on the metal that can lift paint off of the aluminum hull. Magnesium has a higher degree of anodic protection than zinc, but this higher protection is too great to be useful on aluminum boats or out-drives in salt water. Aluminum anodes have a slightly higher degree of protection than zinc, but without the harmful over-protection of magnesium. However, pure aluminum anodes will quickly form an oxide layer that electrically insulates the aluminum, defeating the purpose of the anode. (Zinc also forms oxides in fresh water, which insulates it and prevents it from working.) Toward the end of the twentieth century, certain aluminum alloys were developed to make them superior to other sacrificial anodes. One of these alloys is made of 95% Aluminum, 5% Zinc, and .02% Indium, and is marketed by Performance Metals Products under the trade name of “Navalloy®.”

hull anode

Navalloy Hull Anode

Performance Metals Products manufacturers a complete line of sacrificial anodes for boats of all types, using their aluminum alloy Navalloy.  Navalloy has many properties that make it ideal for sacrificial anodes on our boats. This alloy has all the advantages of aluminum, without the disadvantages of pure aluminum or the toxicity of zinc. Navalloy is lighter than zinc and lasts 30 to 50% longer than zinc anodes. It has a higher protection voltage than zinc, but not dangerously high as with magnesium.

Performance Metals Products anodes have built-in wear indicators in them. The more traditional anodes, such as hull anodes, shaft anodes, and rudder and trim tab anodes have a red dot cast under the surface of the anode, when the dot is visible; it is time to change the anode. Their pencil anodes, used on the inside of heat exchangers and other engine parts, have the anode cast around a stainless steel core, which allows the anode to dissolve without the remainder breaking off and potentially causing water blockage problems as it moves around loose in the engine. These pencil anodes also work well in hot water, typically found within the cooling circuits of marine engines, heat exchangers and refrigeration condensers. Zinc anodes provide greatly reduced protection in hot water. Zinc anodes form a non-porous layer when the boat is hauled out of the water, which must be cleaned before the boat is launched. Navalloy does not form this layer, and work immediately upon re-immersion in water.

Environmental agencies have determined that zinc anodes are a major cause of pollution in marinas. Maryland is currently considering phasing out the use of zinc anodes in favor of aluminum alloys to solve this problem with zinc in marinas and boatyards.

Navalloy anodes are made to military specification MIL-DTL-24779B(SH).

Mercury and Johnson/Evinrude/OMC started selling aluminum alloy anodes in the early 1990’s. Other outboard and out-drive manufacturers also are switching to aluminum anodes. Some of the manufacturers may void the warranty coverage of their products if zinc anodes have been used.

Since Navalloy anodes provide better protection, are less toxic, last longer, work in all waters and weigh less, are there any reasons to keep using zinc anodes?

shaft anode

Navalloy Shaft Anode

Mark McBride – February 14, 2013

Electrical Wire Terminations

January 29, 2013

In the boat and yachting electrical world, it is not enough to merely strip the insulation off the end of a wire and wrap it around a screw that gets tightened.  Wire terminals are the approved method of connecting wire ends to the source of electricity and to electrical devices that require it.

Marine wire has specific qualities that make it superior for use on boats and yachts.  Marine wire should be finely stranded copper, for flexibility, as marine wiring must be able to survive long periods of vibration without failure. The individual strands making up the wire should to be tin plated to resist corrosion. The wire insulation must be able to withstand the heat, moisture, salt, fuel, oil, acid, and abrasion which are usually present in this harsh environment.

Marine wire terminals also should be made of copper, and have tin plating for corrosion resistance. Marine wire terminals should be insulated and of the crimp-on type electrical connection.

The wire terminal must be selected to match the size (gauge) of terms and toolwire being used. In the smaller wire terminal sizes, the terminals are often color coded, RED for 22-18 ga., BLUE for 16-14 ga., and YELLOW for 10-12 ga. Always use the correct sized terminal for the wire gauge being used.

When using ring terminals, always select the correct ring terminal for the size of the fastener used to attach the terminal. It is important to maximize the surface area between the terminal fastener and the wire terminal itself to improve the current carrying capacity of the wire and terminal connection. A 3/8” ring terminal attached to a #10 screw doesn’t allow much surface area for the current to flow and has little resistance to bending or vibration. It is possible to modify the size of the ring terminal on some of the larger sizes. A 2/0 x ¼” ring terminal can be drilled out with a step drill to a 5/16”, 3/8”, or larger.  However, drilling out the terminal will remove the tin plating on the inside of the hole, which compromises the anti-corrosion properties of the plating.

There are actually two connections that need to be made for each wire terminal. The first is the ELECTRICAL connection,electrical crimp connecting which is made by crimping the middle part of the terminal sleeve to the bared wire strands with the appropriate section of the crimping tool. This section is usually labeled or color coded for the specific terminal size being used.  The second is the MECHANICAL connection, made by either crimping the end of the terminal sleeve to the insulation at the end of theinsulation crimp connecting wire before the bared strands with the appropriate section of the crimping tool, or by heating the adhesive lined heat shrink tubing around the terminal and wire end insulation.

It is essential to make the electrical crimp connection with enough force to tightly bond the terminal to the wire strands of the bared wire end. There should not be any play or wiggle between the terminal and the wire it is crimped to. It should be very difficult or impossible to pull the wire out of the terminal after it has been crimped to the wire end.

The mechanical connection is important because it moves the strain of flexing and vibration between the copper wire strands and the terminal to the connection of the terminal to the insulation, preventing the copper strands from work hardening and breaking when subjected to vibration and/or flexing.

The mechanical connection may be a second crimp to a crimping sleeve built into the terminal designed to crimp against completed crimpthe wire insulation. This connection uses a different section of the wire crimp tool than the electrical connection section. This section has a larger “hole” when closed, and allows the mechanical sleeve in the terminal to be crimped to the wire insulation without crushing the terminal as much as with the electrical connection crimp.

Another method of making the mechanical connection is with crimp-on terminals heat shrink before crimpsupplied with adhesive lined heat shrink tubing. The electrical crimp connection is the same, but the mechanical connection is made by shrinking the terminal heat shrink insulation around the terminal electrical connection using a heat source such as a heat gun or small flame. Be careful not to over heat the tubing if using a electrical crimp on heat shrink terminalflame. Hold the flame about an inch or so below the terminal connection and roll the terminal over the flame to evenly warm the heat shrink tubing. Smoking and blackening is a sign of overheating or heating too quickly. The heat will shrink the tubing to form a tight seal, and when enough heat has been applied the adhesive can usually be seen oozing out from the ends of the insulation. The heat shrink process adds the benefit of very good water protection at the wire termination.

heat shrinking ring terminal insulation with flame

If the terminal being used is of the type without heat shrink and without a mechanical crimp connection, a short length of the appropriate sized adhesive lined heat shrink tubing should be placed over the end of the wire before the terminal is crimped, andfinished heat shrink ring terminal heated to shrink around the terminal electrical connection and the wire insulation after crimp has been made. This will provide the necessary mechanical connection to the wire insulation as well as add water protection to the wire end and terminal.

Mark McBride –  January 29, 2013

There are two main types of power tilt and trim motors and pumps that are designed for recreational boats that have an outboard or a stern drive.

Older power tilt and trim systems use an electric tilt motor and a mechanical lifting device. On stern drives, the electric motor turns a worm gear and uses a wet clutch pack to tilt the drive unit and lock it into place.

Tilt & Trim Motors and Pumps

More modern boats, such as Johnson, Evinrude, Mercruiser and Volvo Penta stern drives, commonly use an electric / hydraulic power trim and tilt system. This arrangement consists of a 12-volt electric motor with a reservoir and a hydraulic pump or valve body.

Problems with the hydraulic pump or valve body manifest themselves when the trim and tilt motor seems to be functioning properly, but the engine or drive unit won’t stay trimmed, or bleeds when in the upside down position.

In this case, boaters are advised to replace their trim and tilt hydraulic pump and fill the reservoir with the proper power trim and tilt fluid. Captains are cautioned to not use transmission fluid, as the detergents in this solution can wear on the systems’ seals.

Visit the Replacing Power Trim and Tilt Systems comprehensive article to aid in trouble shooting and the common problems with power tilt and trim systems.

Canadian Built Tampa Fireboat in Action

A multi-million dollar vessel owned by the Tampa Bay Fire Department in Florida boasted its cutting-edge pumping technology on Wednesday morning, when it put out a major fire at the Port of Tampa.

Early on June 16, several rubber conveyor belts at the port went up in flames, and the Patriot, the new fire boat, came to the rescue, myFox Tampa Bay reports. “With this vessel, the way that it’s built, its set up not only as a fire fight vessel but also as a command and control vessel,” Captain Bill Wade told the news source.

“[The firefighters] can control the situation from their side and make sure that fire crews are acting safely, because fighting a ship is much different than fighting a fire in a building.” Among its features, the Patriot can pump a total of 13,500 gallons of water per minute, which is the equivalent of nine fire trucks.

While recreational boaters don’t need the high magnitude of pumping power required by the fire department, marine pumps nonetheless prove useful to all boat owners. A modern 40’ vessel may have a dozen pumps or more, serving a myriad of functions aboard a modern yacht.

Bilge Pump

An electric bilge pump can remove water that accumulates in a bilge at a rate of about 60 gallons or more per minute. Fuel transfer pumps are typically vane pumps that offer reversible operation. Engine driven pumps can serve for engine cooling, or exhaust cooling. Freshwater pumps can supply water to all the fixtures aboard, transfer water, be used in a bait-well or deck wash-down situation. Finally, macerator pumps and be used to grind waste from a marine toilet, eventually pumping out the slurry mixture when the boat is docked.

Three Wire Tilt & Trim Motor

When boaters experience problems with their power Trim and Tilt Motors, the first step is diagnosing the cause of the trouble. Captains will have to determine if the issue is with the power Trim and Tilt Motor, the Hydraulic Pump Valve Body assembly or in the 12 volt power system.

First confirm that there is power to your Tilt and Trim motor and that you have enough power to do the work. Check the battery voltage and the connections of all the electrical wires.

All power trim motors use a 12 volt DC reversing motor and contain both a blue and green wire. The blue wire raises the motor when energized, while the green one lowers the drive unit. Some systems also have a black wire, which functions as a ground on units that don’t ground through the case.

Two Wire Tilt & Trim, Motor w/ Reservoir

To diagnose a Trim and Tilt Motor error, use a jumper wire to apply 12 volts to the blue or green wire, which should cause the drive unit to rise or fall, respectively. If the motor runs, the problem is likely an issue with a solenoid or a lack of voltage from the power Trim and Tilt switch to the solenoid.

If the power Trim and Tilt Motor doesn’t run after the diagnostic procedure, a replacement motor is needed. Often, replacement Power Trim and Tilt Motors include a kit to convert three-wire systems to a more powerful two-wire unit.

Visit Replacing Power Trim and Tilt Systems to aid in trouble shooting and the common problems with power tilt and trim systems.

Blue Sea Systems continues to be a leading manufacturer of electrical panels and electrical components for boaters; whether building new or refitting your boat. Go2marine supplies electrical products for powerboats or sailboats as well as commercial and fishing vessels.

The Blue Sea name is synonymous with quality marine electrical products. There is a crafted Blue Sea marine electrical distribution panel to fit every need. Panels are available in AC (alternating current, 110 volts), DC (direct current, 12 volts), a combination of AC/DC as well as waterproof DC panels. As years have gone by, boats have increased in their electrical complexity with the addition of GPS, computers, LED lights and other systems. Blue Seas panels help the average boat owner when doing an electrical panel replacement or installation. Benefits include increased electrical safety as well as updating the panel for the demand in modern electrical use.

AC Electrical Distribution Panels:

DC Electrical Distribution Panels:

AC/DC Electrical Distribution Panels:

DC Weather and Water Resistant Distribution Panels for cockpit, helm and spray situations.

Blue Sea panels are easy to use and modify. There are circuit breakers available to fill open positions left in panels for customization or to replace breakers with ones that more approximate your panel requirements.

Thermal Circuit Breaker / Switch Combination

Thermal circuit breakers combine switching and circuit protection. Typical uses for these are as a switch / breaker to a downrigger, electric outboard, winch or any electric motor. Use in any location where power is coming directly from the battery to an electrical device. These thermal circuit breakers are waterproof and vaporproof and may be used aboard gasoline powered boats with no risk of spark.

Battery Switches

Most modern boats of any size have a battery switch. In a simple system, the battery switch just cuts the electricity from the batteries to the engine, or the “house” (the term for batteries that run the boat electrical systems other than the engine) or both.  As boats get larger, they may use more than one for a variety of reasons. The power coming from a group of batteries is sorted out into banks, for the house and engine. Add to this a separate generator starting battery, inverter and battery charger and you may have more than one switch to direct all the different power sources to the distribution panels or applications. Blue Sea Systems manufacturers a battery selector switch for any application.