Sig Marine Sig100, Sig120, Sig170, Sig180 Operating And Installation Instruction Manual

Natural Draft Diesel Heater

Operating and Installation

Instruction Manual

*KEEP THIS MANUAL FOR FUTURE REFERENCE*

Sig100, 120, 170, 180

** Please read from beginning to end before installing and operating.

Heater’s Serial #: __________________

Form#7.2-256 Issue#2 Sept 5th, 2012

Quality Controlled by- Doug & Don

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WARNINGS

- Do not operate this heater unattended.

- Turn off the heater when refueling.

- Do not burn gasoline.

- When operating the heater there MUST be an open fresh air vent.

- Do not light a warm burner or it can result in an explosion.

- Do not use a pressurized fuel tank.

- Do not plug the overflow fitting.

- Install a CO alarm.

- Follow ALL installation and operation procedures.

1. About a Natural Draft Diesel Heater

A Sig Marine diesel heater has many advantages to other heating appliances.
They can be run on no power but has a 12v draft assist fan to provide draft
assistance. Our heaters are equipped with simple but reliable internal
components including a gravity feed oil metering valve to a vaporizing oil
burner where the fuel vaporizes by natural draft to burn a beautiful clean fire
in the viewing combustion chamber. A vaporizing oil burner is designed to
transform oil to a vapor state and then burn the vapor. Vaporizing is
achieved by the oil reaching 465 F. Once the oil is vaporized, it becomes
flammable and an efficient and clean combustion is the result.

To obtain a clean and efficient combustion, 3 factors must be in a balanced
proportion.

1. Draft- the volume of air rising through the exhaust chimney.

2. Oxygen- replacement supply of fresh air.

3. Fuel- Input in proportion to the supply of draft and oxygen.

Sig Marine diesel heaters can also be calibrated to run kerosene (K) and
stove oil (S). See “Fuel Variations” on Pg. 23. This code will be indicated on
the side of the valve.

A hot water coil can be factory installed or added later to also enjoy water
heating from your Sig Marine diesel heater only on the Sig180 models. Hot

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water coils are available in a 1 turn coil to heat approx. 5-10 gallons of
water. Hot water coils are also available in 2 turn coils to heat approx. 15-20
gallons of water.

2. Important Notes

Here are some important notes to remember when installing a Sig Marine
diesel heater:

• Mounting & location, 12v power hook-up, minimum 4ft and a
maximum 10ft of chimney, the location of hole for the chimney & the
fuel supply.

• VERY IMPORTANT: Unrestricted permanent fresh air inlet
required to draw in outside air needed for correct operation.

• Fuel must be filtered and not exceed a pressure of 4 psi or a fuel
pressure regulator must be used to avoid dangerous flooding.

• A barometric damper must be installed to help regulate the draft. A
barometric gives you more control in the “fuel to air” mixture needed
for correct operation. The valve controls the fuel whereas the fan
increases the air and the barometric decreases the air (See Pg. 7/8).

• Install a CO alarm.

3. Ventilation

Do NOT operate this heater in an enclosed area without a permanent fresh air
inlet designated for your heater. This is required to draw in outside air for
correct operation. To guarantee that fresh air is available for your heater, good
ventilation is essential. You MUST replace the air inside your boat at the same
rate that the heater is removing it. The higher the heater’s burning rate, the more
air the heater will require. If the air flow is blocked or restricted, the heater will
burn inefficiently, create soot, blow out and can even be a very dangerous health
hazard.

A permanently open fresh air inlet MUST be installed or dedicated to the heater.
This inlet must be at least 3" in diameter. Ducting to the heater is also an option.

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It is important to create and maintain a positive pressure inside the boat. High
winds can draw air out from the boat and thus create a negative pressure. This
condition can result in down drafts. Ensure that when you do have windows
open that they do not create a suction effect in the cabin due to the window’s
position and the wind direction. In a similar way, it is possible for the air intake
on your engine to suck the air out of a cabin if it is not properly vented.

Your heater is a natural draft appliance and it creates its draft pressure like a
chimney in a wood stove. The rising, heated air in the chimney pulls fresh
air into the heater as it rises up the chimney and exits the flue cap. The
greater the draft pressure, the more able the heater will be to resist strong
winds, overcome flue elbows that inhibit draft and the hotter you will be
able to get your heater without sooting. A CO alarm should be installed in
the boat. We also recommend the high heat shut-off kits available through
us.

4. How Does the Chimney affect the Heater?

The heater does not create the draft for a natural draft appliance to operate; it
is the chimney that creates the draft for operation. The purpose of a chimney
is to take the combustion products (smoke and gasses) from the appliance to
the atmosphere outside your boat, and at the same time, to draw air in for
combustion into the appliance. This movement of combustion air and
exhaust is called draft.
In essence, it is the difference in pressure between the air inside the chimney
flue and the outside air that creates this movement. Warmer, lighter gases in
the flue will move upward.

To keep the pressure conditions favorable, we need a tall column of warm
air inside the chimney, and cooler air outside. The warm air will tend to rise,
drawing the exhaust from the appliance out. As air exits the chimney, fresh
air for combustion is drawn into the appliance. The stronger the upward draft
in the chimney the more likely you won’t experience downdraft.

Important Factors of the Chimney

Since draft is a measure of pressure, chimney draft is affected by pressure
conditions in the boat. Several factors come into play:

1. Adequate air. First, there must be adequate air movement into the
boat to make up for the air exiting through the chimney. If the boat is
very tightly insulated, the volume of air drawn up the flue will exceed

the volume of air entering the boat, and the boat will gradually
become depressurized. With lower pressure in the boat than outside,
there will be a tendency for air to be drawn back into the boat from all
available openings including down the chimney.

2. Air movement in the boat. Second, air movement in the boat must
not interfere with the chimney. As air flows out through the one
window, air is drawn from another to replace it. This is called the
stack effect, since the boat acts like a stack, or chimney. If the stack
effect is powerful enough, it will overcome the chimney's upward
draft and pull replacement air (and smoke) into the boat through the
chimney.

3. Competition for available air. Third, there must not be too much
competition from other devices in the boat, such as exhaust fans, a
large engine or air-exchange systems. If something else is sucking the
air out of the boat, the chimney might not be powerful enough to
overcome it, and exhaust might be drawn into the boat from the
chimney.

4. Proper chimney design. And finally, a chimney must be designed to
accommodate the volume and type of exhaust being emitted by the
appliances it serves. This involves correct sizing, adequate height, and
proper construction. See the “Chimney Pipe” section on pg. 9.

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Since the chimney draft is affected by so many factors, draft problems
can be complicated to find.

Testing the Draft

To find where the air is being drawn, twist a paper towel into a wick, light it
and blow it out to create smoke. Placing the smoking wick near the open
hatches, windows or vents will lead you to the location. Installing or opening
opposing vents will allow the air to come in from a path of least resistance
and not disturb the draft in the chimney.

Downdraft

A common reason for downdraft is burning the heater too low (too much air
in the burner and not enough fuel). If the flames are burning below the top
burner ring and inside the burner pot then it is burning inefficiently causing
the draft to be too weak going up the chimney allowing downdraft down the
chimney. When the flames are burning above the top ring then the natural
draft is at its strongest so it can fight against downdraft.

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5. Installing your Heater

Location

Plan your heaters location prior to installing to ensure the location chosen
will fit the specifications and safety clearances. Combustible material closer
to the heater then the specified safety clearances must be lined with
insulation or millboard and a metal liner with a .5” standoff for air
movement behind. Another alternative is using insulation or millboard and
ceramic tile. The wall behind the heater and the first length of chimney pipe
should also be lined with such material. See diagram below.

Safety Clearances

Above- 30”, In front- 18”, Sides- 12”, Below- 6”

Facing Direction

The heater ideally should face the bow or stern of the boat, particularly on a
sailboat. Fuel is gravity fed from the oil metering valve into the burner so if
the valve should drop below the level of the burner, the fuel would not flow
uphill into the burner, which will put out the fire. In a beam-facing
installation, the oil metering valve may have to be relocated to the side of the
heater. See diagram below. This will allow the heater to operate up to 15
degrees. If you need the valve mounted on the side, the heater would need to
be special ordered from the factory, please email us. [e-mail]

Note: the heaters valve & burner should be in line with the boats keel.

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Mounting

The Sig heaters have the appropriate brackets to secure the heater to the
bulkhead. The drip tray will then fit under the bottom of the heater.

**REMEMEBER: remove all protective plastic on ALL parts of the heater.

Chimney Pipe

The location and configuration of the chimney stack is very important to the
operation of the heater. A long, straight chimney stack will ensure a strong
draft for correct operation. The diameter of the chimney must be what is
specified. We recommend that the length of your chimney is a straight 5-6ft
run with a minimum of 4ft long and a maximum of 10ft. Avoid using elbows
and if necessary, use 45 degree elbows and allow for as much straight pipe
as possible with a minimum of 12” (28 cm) from the top of the heater. There
is no connector to connect the chimney pipe to the heater. There is a flue
collar already attached to the top of the heater and the pipe can attach by
squeezing the pipe into an oval shape and fitting it over the flue collar.

Chimney Pipe Diameters

All Sig Heaters- 3” diameter chimney (7.5cm)

Barometric Damper

We have 2 options for installing the barometric damper into your chimney.
You can either have the barometric attached to a 22” stainless pipe to be the
first piece of pipe of your chimney off the top of the heater or a 7” piece of
pipe that you can fit into your chimney 12” to 24” from the top of the heater.

All model heaters:
Part# S16-001: 3” x 22” stainless pipe with barometric
Part# 900287: 3” x 7” stainless pipe with barometric

The barometric damper should be installed in oil and solid fuel heaters. The
purpose is to maintain a strong draft without causing too much air to the
“fuel to air” mixture. When the damper is adjusted, the draft is altered by
allowing air to be pulled into the chimney by the air inlet on the damper and
not pulled into the burner. This gives you more control. Having a barometric
allows you to burn your heater at lower temperatures giving you the control
to adjust the draft once the fuel is adjusted to ensure a clean burn.

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Install the barometric tee pipe with the front flap facing fore and aft. In order
for the barometric to work efficiently it must be installed between 12” and
24” from the top of the heater. If using a flue guard, turn the barometric tee
to the back as it does not have to be seen to work

To adjust the flap on the barometric, back off the jam nut and turn the
counterweight so the flap is standing closed. Once the heater has been
burning for some time and the room temperature is starting to rise, it is a
good time to do the adjustment. Adjust the counterweight so the flap starts to
open (aprox 6mm or ¼”). This will allow air to enter the barometric tee and
reduce the air entering the burner. This will help the flame to burn above the
top burner ring. If the flame is still burning below the ring, adjust the flap
open another 3mm or 1/8”. At this time, if there is flames burning below the
top burner ring and the barometric flap is open aprox 9mm or 3/8”, do not
adjust the flap open any further and increase the valve setting until the flame
is burning above the top ring.

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Deck Fitting

To install the thru deck fitting, a hole must be cut in your deck. Depending on
the diameter of the chimney stack will depend on the size hole that needs to be
cut. There should be a 1” clearance all around the chimney pipe. For example, a
3” diameter exhaust pipe would require a 5” hole drilled in the deck. Once a
hole is cut, you can line the raw hole with epoxy, caulking or a metal liner to
finish it off. Just ensure there is a 1” air gap between the side of the hole and the
chimney pipe.

The thru-deck fitting includes a stainless steel dress ring for the interior of
the cabin and a neoprene rubber gasket to better seal the fitting on the deck
side. Depending on the contour or the angle of the cabin top, you may need
to make a hardwood spacer block. One surface of the block would be a level
plane to mate to the deck cap. The other would match the angle or contour of
the cabin top. A hole through the center of the block would also be 2 inches
greater then the diameter of the flue pipe.

Exhaust Cap

The DP round or H style exhaust caps are most recommended. The exhaust
cap will fit over the crimp on the deck fitting or flue pipe. The location of
the exhaust cap above deck must be clear of any immediate obstruction that
may cause unusual air movement or turbulence. CAUTION: The Exhaust
Cap gets hot when the stove is operating.

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Heater Installation Diagram

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6. Fuel System Installation

For efficient and safe operation of the heater, follow all recommendations
for properly installing the fuel system.

DANGER: Never use gasoline in a heater. Use only #2 diesel, #1 stove oil
or kerosene. The valves are factory calibrated to #2 diesel; if #1stove oil or
kerosene is preferred, the valves can be re-calibrated to suit those viscosities.
*** If in colder temperatures it may be wise to burn kerosene or add fuel
additives to your fuel to keep the fuel viscosity thin for correct operation. In
some cases, a valve with a higher flow rate may be needed.

Fuel Supply & Overflow Feature
The fuel supply fitting on the oil metering valve is a 1/8” NPT fitting and

the overflow is also a 1/8” NPT fitting. Copper tubing should be used for the
first 3 feet of fuel line from the heater. Approved hose can be used for the
remainder of the installation. Run the fuel lines as straight as possible to
avoid air locks. Check all connections for any leaks.

The overflow safety feature is designed to allow the controlled escape of
fuel from the heater in case of over pressurization. If dirt, debris, or too
much pressure gets into the needle and seat inside the valve, the fuel will rise
and overflow out of the valve and away from the heater. It is common to get
a few drips now and then from the movement in rough waters, however,
more then a few drops of fuel from the overflow indicates the need to
service and clean the valve.

Under NO circumstances plug the overflow fitting!! A fuel line must be
taken from the overflow fitting back to the main tank if the fuel is supplied
from the main tank. If the fuel is supplied from a day tank, then run the
overflow line to a container away from the heat source. The fuel overflow is
a gravity escape. Do not install the overflow line so that is goes up or in
loops as this will cause an air lock and block the fuel from escaping. Plastic,
rubber or copper tubing may be used for the overflow line.

Note: If the your fuel tank vent or fill tube is higher than the valve of the
heater, and the overflow of the heater goes back to the main tank, there may
be a chance when re-filling that the fuel will back flow up the overflow and
out of the valve. For this reason a manual shut-off will need to be teed in the
overflow line and closed when refilling tanks. CAUTION: After refilling,