Sig Marine Sig200, Sig250 Operating And Installation Instruction Manual

Natural Draft Diesel Stove

Operating and Installation

Instruction Manual

*KEEP THIS MANUAL FOR FUTURE REFERENCE*

Sig200 & Sig250 Stove Models

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

Stove Serial #: __________________

WARNINGS

- Do not operate this stove unattended.

- Turn off the stove when refueling.

- Do not burn gasoline.

- When operating the stove 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.

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1. About a Natural Draft Diesel Stove

A Sig Marine diesel stove 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 stoves 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 stoves can also be calibrated to run kerosene (K) and stove
oil (S). See “Fuel Variations” on Pg. 27. 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 stove. Hot water coils are available in a
1 turn coil for all model stoves to heat approx. 5-10 gallons of water. Hot

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water coils are also available in 2 turn coils for all models to heat approx.
15-20 gallons of water.

2. Important Notes

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

• 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 (Sig
Marine part# 15074).

• 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. 9).

• Install a CO alarm.

3. Ventilation

Do NOT operate this stove in an enclosed area without a permanent fresh air
inlet designated for your stove. This is required to draw in outside air for correct
operation. To guarantee that fresh air is available for your stove, good
ventilation is essential. You MUST replace the air inside your boat at the same
rate that the stove is removing it. The higher the stove’s burning rate, the more
air the stove will require. If the air flow is blocked or restricted, the stove 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 stove.
This inlet must be at least 3" in diameter. Ducting to the stove 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 stove 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 stove as it rises up the chimney and exits the flue cap. The
greater the draft pressure, the more able the stove will be to resist strong
winds, overcome flue elbows that inhibit draft and the hotter you will be
able to get your stove without sooting. A CO alarm should be installed in the
boat. We also recommend the Sig Marine high heat shut-off #15103.

4. How Does the Chimney affect the Stove?

The stove 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 back 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 Stove

Location

Plan your stoves location prior to installing to ensure the location chosen
will fit the specifications and safety clearances. Combustible material closer
to the stove 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
back of the stove and the first length of chimney pipe should also be lined
with such material. See diagram below.

Safety Clearances

Above- 3ft, Sides- 2”, Behind- 2” *with protective material.

Facing Direction

The stove 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
stove. This will allow the stove to operate up to 15 degrees. If you have any
doubt regarding this, please email us. [e-mail]

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

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Mounting

There are holes provided in the side panels at the front of the stove to allow
appropriate fasteners to secure it to the cutout. There is also a tie down bar
supplied to fasten to the bottom back of the cutout, once fastened, side the
stove into the cutout so the side panels are hooked underneath the bar. The
drip tray will then fit under the bottom of the stove.

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

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Chimney Pipe

The location and configuration of the chimney stack is very important to the
operation of the stove. 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 stove. There is a flue
collar already attached to the top of the stove and the pipe can attach by
squeezing the pipe into an oval shape and fitting it over the flue collar.

Chimney Pipe Diameters

The Sig200 and 250 are available both with a 4” and a 5” chimney diameter.

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 stove or a 7” piece of
pipe that you can fit into your chimney 12” to 24” from the top of the stove.

4” Chimney:
Part# S17-001: 4” x 22” stainless pipe with barometric
Part# 900288: 4” x 7” stainless pipe with barometric

5” Chimney:
Part# S18-001: 5” x 22” stainless pipe with barometric
Part# 900289: 5” x 7” stainless pipe with barometric

The barometric damper should be installed in the oil stoves chimney. 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 stove at lower temperatures giving you the control
to adjust the draft once the fuel is adjusted to ensure a clean burn.

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

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24” from the top of the stove. 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 stove 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.

Tie Down Bar Install

The tie down bar is for securing the back of the stove. Install the bar at the back of
the cut-out so the stove bottom will slide under it. There are screw holes for the
front of the stove.

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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
5” diameter exhaust pipe would require a 7” hole drilled in the deck and a 4”
pipe would have a 6” hole. 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 Sig Marine DP 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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Stove Installation Diagram

Securing your Stove

When installing your Sig Marine stove it is recommended that you bolt it
down using the 4 holes provided (2 on the bottom of each leg). The rear bolt
holes can be hard to reach so instead you can use the tie down bar (provided)
instead. Firstly mark where your stove is going to be located. Then screw
down the tiedown bar so that it allows your heater to slide with the feet
sliding underneath the upraised ends. Ensure that the tie down bar contacts
the stove somewhere between the middle and rear of the stove. Once in
place secure the front of your stove through the bolt holes. The tie down bar
alone will not secure your stove. It only prevents upward movement such as
tilting. If not secured otherwise, your stove will be at risk of sliding in high
seas.

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6. Fuel System Installation

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

DANGER: Never use gasoline in the stove. 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 female fitting

and the overflow is also 1/8” NPT female fitting. ACR (refrigeration) copper
tubing should be used for the first 3 feet of fuel line from the stove.
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 stove 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 stove. 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
stove, and the overflow of the stove 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

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overflow line and closed when refilling tanks. CAUTION: After refilling,
you will need to burn off the fuel in the line before re-opening the shut-off
valve. Do not use a check valve. Remember to re-open the shut-off valve on
the overflow line.

Fuel Filter & Manual Shut-off’s
The fuel must be filtered before the fuel pump and before the oil metering

valve to prevent dirt and debris from plugging up the check valves in the
pump and the needle and seat in the valve. There also must be a manual
shut-off by the tank and also close to the stove as the pressure on the needle
in the valve will wear it out faster. We can supply a ¼” NPT fuel filter with
a shut-off for close to your stove for this purpose. (Part# 15076) The 15
micron stone element in the filter (part#15077) should be replaced every 1-2
years.

Fuel Supply

The fuel can be supplied to your stove by either your main tank or a day tank
and fed with either a fuel pump or gravity depending on your install.

Gravity Feed

When using a gravity tank, there should be a minimum head of 12" (30.48
cm) above the fuel level marked on the side of the oil-metering valve to
operate correctly. The gravity feed tank must be vented and all fuel lines
must be as straight as possible to avoid air locks. Do NOT use a pressurized
tank.

The oil metering valve is rated to an incoming fuel pressure of 3 psi. If the
pressure exceeds 4 psi, a pressure regulator will be needed in the supply line.
(Part # 15074) If installing a gravity tank larger then 30gal or higher than 8
feet above the valve of the stove, you will also need a pressure regulator.

Fuel Pump

When a low pressure fuel pump is used, a fuel line must be tee’d in as close
to the fuel tank as possible, not from the engine supply line or engine filter.
Use a check valve in the stove fuel line to stop the engine from pulling back
the fuel and starving the stove.