DeDietrich MCA Pro 115, Инструкция по установке и обслуживанию

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MCA Pro 45/65/90/115 MCA-Pro ISM Rv.4.1 2/2017
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to move in and out as the heating system water
expands due to temperature increase or contracts
as the water cools. The expansion tanks may be
closed or diaphragm, open or bladder type. Refer to
page 30 of this manual for the suggested location
of an expansion tank or air eliminator.
• Closed type is located above the boiler and
welded gas tight and the tank is partially filled
with water which leaves an air cushion for
expansion.
- Ensure that this type of tank is fitted with
a tank fitting (such as Taco Taco-Trol or B
& G Tank-Trol) which reduces the gravity
circulation of air saturated tank water back
into the system and prevents the air from
bubbling up trough the water as it returns
from the system.
- Systems with the closed type tanks cannot
use the automatic air vents. Instead of
returning to the tank, the air will escape
from the system. This will lead to the tank
eventually becoming waterlogged and no
longer being able to control pressurization
and the boiler relief valve will frequently
weep.
• Diaphragm or bladder type is most often found
near the boiler but may be located at any
point in the system. It is welded gas tight and
has a rubber membrane to separate the tank
pressurizing air and the water.
- At least one automatic air vent is required
by systems with this type of expansion
tank and located preferably on top of an air
eliminator. This is shown in examples found
in this manual.
• Open type expansion tank is located above the
highest baseboard or radiator unit and is usually
found in the closet or attic. This expansion tank
has a gauge glass and an overflow pipe to a
drain.
2. The expansion tank may be undersized or
waterlogged if the relief valve has a tendency to
frequently weep.
• Diaphragm or bladder type expansion tank -
verify that the tank size is large enough for
the system. If the expansion tank is too small,
one or more additional tanks will have to be
added in order to provide sufficient expansion.
If the expansion tank is large enough, remove
it. From the system and check the charge
pressure which is usually 12 psig for residential
applications. If the expansion tank does not hold
the pressure, it indicated that the membrane
has been damaged. The tank will need to be
replaced.
Inspection of the ignition electrode
Inspection of the ignition electrode
1. Remove the ignition electrode plug from the
ignition transformer.
i
The ignition cable is fixed to the ignition
electrode and therefore may not be removed.
2. Unscrew the 2 screws. Remove the unit.
3. Wipe off all traces of deposits using an abrasive
cloth.
4. Check the ignition electrode for wear. Replace if
necessary.
5. Check the gasket.
6. Refit all parts, replacing those that are damaged.
Checking the ignition wiring
1. Check the boiler ground wire from the heat
exchanger access cover to the ground terminal
strip.
2. Inspect and verify that all wiring is in good
condition and attached in a secure manner.
3. Use a continuity meter to check the ground
continuity of the wiring.
4. If after checking the results are not satisfactory,
replace the ground wires.
Checking all the boiler wiring
Check and verify that all boiler wiring is in good condi-
tion and attached in a secure manner.
Checking the control settings
1. Navigate through all the settings using the control
display and adjust settings if needed.
2. Checks and adjust, if needed, the external limit
controls settings (if any).
Perform the start-up and checks
1. Start the boiler and perform the checks and tests
outlined in this manual.
2. Check and verify that the cold fill pressure is
correct and that the operating pressure does not go
too high.
3. The check-out procedure can now be completed as
outlined on page 118 .
Checking the burner flame
WARNING
The MCA Pro boiler contains ceramic fiber materials.
Follow the instructions on page 84 In this manual
when handling ceramic fiber materials. Failure to
heed this warning could result in severe personal
injury.
1. Follow the procedure on below when inspecting the
flame through the observation window.
2. If the flame is not satisfactory at either low fire or
high fire, turn the boiler off and let it cool down.
Remove the burner and thoroughly clean it with
7. Checking and Maintenance