CDL Venturi User manual

OWNER’S
MANUAL
VENTURI
EVAPORATORS
Version 1.0
14/01/2020
© All rights reserved Les Équipements d’Érablière CDL inc.

2CDL Maple Sugaring Equipment inc.
Thank you for choosing a CDL wood evaporator. Our 40 years of experience working
with sugarmakers ensures you that you acquired a high performance, quality piece
of equipment. Before using this product, make sure you understand all the following
instructions. If there is any problem upon receipt of this product, please immediately
contact CDL or your local representative.
FINDING INFORMATION
Make a record for future use
Brand: ______________________________________________________
Purchase Date: _______________________________________________
Model Number: _______________________________________________
Serial Number: _______________________________________________
Serial number location
The serial number is located on the back of the evaporator arch.
Serial number
location

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CDL Maple Sugaring Equipment inc.
SAFETY
A wood evaporator can be a dangerous piece of equipment. Always wear heat resistant gloves
and clothing when you fire an evaporator. Often, visitors can be in the sugarhouse. Make sure
they stay at a safe distance from the evaporator, especially children.
A wood evaporator works with solid material (wood) and produces intense heat in front of the
arch and around the smoke stack. The evaporator should be set up on a concrete or ceramic
floor strong enough to support the weight of the evaporator and its contents, all walls and
rafters should be at least 24” from all points of the smoke stack. If you need to put it closer to
the wall, a heat barrier (ceramic blanket for example) should be installed. Also, make sure that
your steam and smoke stacks have a clear path to the roof of the building (avoid rafters). Your
ceiling should be high enough for you to raise the hoods safely with a cable and pulley system.
IMPORTANT: Make sure to contact your insurance company in order to verify their safety
standards, and requirement for coverage.
If your building is not insulated, you will have better combustion and better steam evacuation.
If it is insulated, you will need to have an air intake inside your building (air trap, open
window etc.)

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INSTALLATION OF THE ARCH
If your building is not insulated, you will have good combustion and a better evacuation of the
steam. However, if it’s well insulated, make sure you have enough fresh air intake to have a
good combustion and enough draft.
1. Remove the wheels under the evaporator.
2. Remove the pans. Level the arch using the adjustable legs.
3. When the evaporator is leveled, tighten the nuts on the legs.
4. The 2’ wide Venturi evaporator has a fixed Venturi system on the smoke stack.
It only requires a 110 volt plug in.
5. All the Venturi evaporators, 2-1/2’ and wider have a Venturi system that can be installed
remotely to lower the noise level. You just have to install an adaptor and enough pipe to
hook up the blower to the smoke stack. Try to minimize air flow restriction by installing the
blower as close as possible to the evaporator and by using long radius elbows if necessary.
6. The Venturi system must be hooked up in the first section of smoke stake on top of the base
stack.

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CDL Maple Sugaring Equipment inc.
BRICKING
The Venturi evaporator is delivered with the ceramic wool already installed. All you have to do
is to brick the combustion chamber.
Follow these steps.
Call your CDL sales representative if you need further assistance.
1. Start with the bottom between the grates and the front, sides and back of the arch. Leave
3/16” between the grates and the bricks for expansion.
2. Build the side walls, one row at the time. Make sure to lean the brick against the wool on
each side of the arch.
Here’s what the final product should look like:
3. Let the cement dry for 24 hours.
4. It’s now time to cure the cement and the bricks. Fill the pans with water as if you were going
to boil sap. Start a fire and bring the temperature inside the burning chamber between
400°F and 500°F for an hour. Do not start the Venturi system during this operation. Also, do
not exceed 500°F and make sure the pans don’t run out of water. Keep at least 2” of water
in each syrup pan and at least 2” of water above the flues at all time.
5. Let the evaporator cool down for 24 hours.
Front view
Close-up of the wall
Side view

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ASSEMBLY
The insulation and bricking are completed. Here’s how to put together the pans and stack.
1. Set the pans on the evaporator starting with the flue pan. Make sure the back of the pan
touches the back plate (or the reheat pan if you have one). Then, install the syrup pans in the
front. Make sure the evaporator and the pan are leveled. Finally, tighten the pans together
using the pan tightener.
2. Install the float boxes, all the connections and the level(s). Hook the sap / concentrate line
from the tank to the back of the rear float box. The bottom of the tank needs to be at least
12” higher than the maximum level in the evaporator. Don’t forget to put Teflon tape on the
threaded parts to avoid leaks.
3. Install the base stack on the back of the evaporator.
4. Install the first section of smoke stack (the one with the Venturi system), on top of the base
stack.
5. Install the roof jacks on the roof. Make sure you seal the installation properly to avoid leaks
inside the sugarhouse.
Front float box
Arch
Level
Sap entry
(back of float box)
Rear float box
Base stack
Flue pan
Pan tightener
Syrup pan
Draw-off valve
Connections
Door

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CDL Maple Sugaring Equipment inc.
6. Install the remaining smoke stack and the steam stacks (if you have hoods). Then install
the collars around the stacks, above the roof jacks.
7. Install the Chinese hats or/and the rope operated stack covers. In the case of the stack
covers, make sure the dominant winds will close them.
8. The last step is to install the steel wires holding the stack in place. Make sure not to tighten
too much. The chimney will expand significantly with the heat.
INSTRUCTIONS
Only use dry wood, without paint or other chemicals (no treated wood). Never use any products
made of plastic, tires, coal or any other combustible material. The use of any unauthorized
combustible will void the warranty.
To optimize combustion, the best length for the wood used in the Venturi evaporator is 20”. The
grates inside the burning chamber are 20” long. So with 20” logs, we get the maximum benefit
of the air drawn in the burning chamber.
The quality of the wood that will be burned is an important factor in the performance of the
evaporator. Poor quality wood will reduce the boiling rate, you will fill the burning chamber
more frequently and the maple syrup produced will be darker. See table 1 to find the heat
potential for each type of wood.
Table 1
Heat produced by each type of wood(Millions BTU per cord)
Oak 29 Elm 25 White pine 17
Sugar maple 29 Red maple 24 Spurce 16
Beech 28 Larch 24 Fir 16
Yellow birch 26 White birch 23
Ash 25 Poplar 18

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OPERATION OF THE EVAPORATOR
Before firing the evaporator
1. Make sure the outlet of the tank feeding the evaporator is at least 12” higher than the sap
level in the flue pan and that the tank is hooked up properly to the back of the rear float box.
2. Install a syrup thermometer on each syrup pan. Make sure they are calibrated by dipping
them in boiling water and adjusting the temperature at 0 degree.
3. Open the rope operated stack covers.
4. Open the sap valve from the sap tank to the evaporator. Fill the flue pan 2” above the flues.
5. Open the front float box valve and fill the syrup pans 2” deep by adjusting the float in the
front float box.
6. After the start of the evaporator, using the float boxes, stabilize the level in each pan. We
recommend 1” in the flue pan and between 1 ½” and 2” in the syrup pans.
Light the evaporator
1. Lighting the evaporator is done with the Venturi shutoff.
2. Completely open the front grill.
3. Using small dry wood and paper, light the evaporator.
4. Wait until you get a good burn.
5. Fill the combustion chamber (1” from the pans).
6. Start the Venturi system.
7. Leave the Venturi system running at all time, even when you fill the chamber with wood.
8. Adjust the draft with the front grill. Try to maintain a base stack temperature of 750°F.

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CDL Maple Sugaring Equipment inc.
Operation during the boiling process
1. Using defoamer is necessary to the good operation of the evaporator. When the syrup
generates too much foam, the float boxes will have difficulty maintaining a proper level in
the pans and you might run the pans dry. RUNNING THE EVAPORATOR WITH NOT ENOUGH
LIQUID IN THE PANS COULD RESULT IN PERMANENT DAMAGE TO THE EQUIPMENT. Also,
the defoamer helps avoiding the foam from overflowing above the pan walls, preventing a
huge mess.
2. ALWAYS pay attention to the liquid level in all the pans. Adjust the floats in necessary.
3. Maple syrup is ready when the temperature hits 7 degrees above the boiling point of water.
Open the draw-off valve when the syrup reaches this level and close it when the temperature
comes back below this value. An automatic draw-off valve is a very useful option to improve
consistency of the maple syrup. Don’t add wood if the syrup is almost ready. The temperature
under the syrup pans will become too high and you might burn your syrup. Wait after you
draw-off.
4. Repeat drawing-off syrup every time the temperature gets to 7 degrees above the boiling
point. It’s possible that the draw-off temperature may vary over time. This is caused by
variations in the atmospheric pressure. Verify regularly your syrup using hydrometer, a
densimeter or a refractometer to make sure you have the right sugar content.
5. As your confidence level increases, you can lower the liquid level in the pans. The ideal level
in the flue pan is 1” above the flues and 1½” to 2” in the syrup pans. Lower the levels in the
pans boils faster and helps making lighter syrup. Don’t go lower than those levels. Going
too low increases the risk of burning the pans.
6. After each day of boiling, it is recommended to drain the sap in both float boxes.
7. When you are almost done for the day, make sure you have enough sap left in your tank to fill
all the pans 2” higher than the normal sap level. It will compensate for the evaporation that
will keep on happening because of the heat accumulated in the evaporator until it cools down.
If you have any questions, don’t hesitate to contact your CDL sales representative.
IMPORTANT SAFETY NOTE:
THE HEAT IN FRONT OF THE EVAPORATOR WHEN THE DOOR IS OPEN IS INTENSE. ALWAYS
WEAR GLOVES, SAFETY GLASSES AND HEAT RESISTANT CLOTHING WHEN FIRING THE
EVAPORATOR.

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TROUBLESHOOTING GUIDE
Can’t keep a constant liquid level in the pans:
• Use more defoamer. (careful, to much defoamer could alter syrup flavor).
• The silicone part in the float box arm is worned down or misplaced.
• The float box arm needs to be realigned.
• There is a leak in the float, it’s filling with sap. Repair or replace the float.
• The sap tank is too high, there is too much pressure on the float box. Move the tank or install
a pressure control float box.
Sap turns to syrup in the 1st syrup pan:
• It can happen when you start the evaporator. Draw-off enough syrup to get it to the front and
distribute what was drawn-off in the flue pan. This will get the movement forward going.
The heat in the chimney is too hot; the base stack turned red or the evaporator doesn’t boil
much:
• Too much draft, gradually closed the front grill until the problem is fixed.
If you have any other problem, contact your CDL sales representative