Dunkirk 90-50 Installation, Operation & Maintenance Manual page 42

monthly during Heating season
1. Remove jacket front and top panels and check for piping
1.
leaks around relief valve and other fittings. If found, contact
a qualified service agency to repair. DO NOT use stop leak
compounds.
2. Test relief valve. Refer to valve manufacturers instructions
2.
packaged with relief valve.
3. Visually inspect venting and air intake system for proper
3.
function, deterioration, or leakage. If the vent or air intake show
any signs of deterioration or leakage, contact a qualified service
agency to repair or replace them immediately and to insure
proper reassembly and resealing of the vent and air intake
system.
4. Visually inspect the clear vinyl condensate lines and the
4.
PVC condensate drain pipe for proper operation, leakage, and
deterioration. If the condensate lines or drain pipe show any
signs of blockage, leakage, or deterioration contact a qualified
service agency to clean, repair, or replace them immediately.
5. Check the air baffle located inside 1 ½" x 2" flexible coupling,
5.
clean it if necessary and make sure to put it back. Refer to repair
parts diagram, mixer and pressure switch assembly.
periodically during Heating season
Where low water cut offs are used, a periodic inspection of the low
water cut off is necessary, including flushing of float type devices.
Refer to low water cut off manufacturer's specific instructions.
end of each Heating season - annual shutdown procedure
Follow instructions "TO TURN OFF GAS TO APPLIANCE".
If heating system is to remain out of service during freezing weather,
and does not contain antifreeze, drain system completely. If boiler
will be exposed to freezing temperatures, drain condensate lines.
Otherwise, do not drain system or boiler.
annual examination and Cleaning of boiler Components
Before Servicing, turn off electrical power to boiler at service
1.
switch. Close manual gas valve to turn off gas supply to boiler.
mainTenanCe and Cleaning
Cleaning Flue passages between boiler sections.
2.
A.
B.
C.
D.
E.
F.
G.
H.
I.
J.
42
NOTICE
The following service procedures must be
performed only by a qualified service agency.
boiler owner should not attempt these
procedures.
Any buildup of sediment or aluminum oxide (white
powdery or flaky substance) in the flue passages must be
cleaned as follows:
Remove jacket front and top panels. Disconnect
condensate drain line from the barbed fitting on the
bottom of the boiler. Keep the open end of the drain line
above the water level in the condensate trap to prevent
the trap from draining. Disconnect pressure switch hose
from barbed fitting on gas valve. Disconnect 1½ x 2"
flexible coupling from air inlet. Disconnect air by-pass (½"
transparent vinyl tube) from the bottom of the mixer.
Remove air baffle from ½" x 2" flexible coupling and clean
air baffle if necessary. Refer to repair parts diagram, mixer
and pressure switch assembly.
Confirm that manual gas valve is closed and disconnect gas
line to gas valve at union. Disconnect wires to gas valve.
and igniter.
Loosen but do not remove five (5) nuts attaching mixer
assembly to boiler. Remove two (2) igniter screws and very
carefully remove the igniter. Use care when removing the
igniter, it is very brittle!
Remove five (5) nuts and remove mixer assembly. Remove
burner and mixer gasket.
Aluminum oxide deposits are water soluble and may be
rinsed away with spraying or running water. Before rinsing,
connect a ½" I.D. hose to the barbed fitting on the bottom
of the boiler and run the hose to a bucket or drain.
After rinsing, remove any remaining loosened sediment
using a shop vacuum with a snorkel attachment.
Inspect burner for any foreign matter in the flame ports or
inside the burner. Any foreign matter should be removed
by blowing with compressed air or vacuuming.
Inspect interior of mixer for any signs of sediment or
aluminum oxide and clean if necessary.