Mestek IIEB-11, Installation & Parts Manual

Page: 19 / 32

19
MAINTENANCE
3. To clean or replace the main burners, remove the
bottom panel and compress the spring by moving
the burner toward the manifold. Slide the opposite
end of the burner downward from the locating slot
while retaining spring is still compressed. Pull the
burners away from the heater.
4. With the burners removed, gently wire brush the
inside surfaces of the heat exchanger.
5. Remove any dirt, dust, or other foreign matter from
the burners using a wire brush and/or compressed
air. Ensure that all parts are unobstructed. Inspect
and clean pilot burner if necessary.
6. Reassemble the gas unit heater by replacing all
parts in reverse order.
7. Complete the appropriate unit start-up procedure
as given in the “Operation” section of this manual
(see lighting instruction plate on the unit).
8. Check the burner adjustment. See the “Primary Air
Shutter Adjustment” section of this manual.
9. Check all gas control valves and pipe connections
for leaks.
10. Check the operation of the automatic gas valve and
the power venter assembly by lowering the setting
of the thermostat, stopping the operation of the
gas unit heater. The gas valve should close tightly,
completely extinguishing the flame on the main
burners.
11. Inspect and service the motor/fan assembly. To
maintain efficient air flow, inspect and clean the
fan blades and guard to prevent buildup of foreign
matter.
12. Check lubrication instructions on the motor. If oiling
is required, add 3 to 4 drops of electric motor oil as
follows:
a. Light Duty - After 3 years or 25,000 hours of
operation.
b. Average Duty - Annually after 3 years or 8,000
hours of operation.
c. Heavy Duty - Annually after 1 year or at least
every 1500 hours of operation.
Never over oil the motor or premature
failure may occur!
13. Check and test the operational functions of all
safety devices supplied with your unit.
PILOT ADJUSTMENT
1. Remove the pilot adjustment cap.
2. Adjust the pilot screw to provide a properly sized
fl ame.
3. A proper pilot flame is a soft steady flame that
envelopes 3/8 to 1/2 inch (9.5 to 12.7mm) of the
fl ame sensor tip.
4. Replace the pilot adjustment cap.
PERIODIC SERVICE
NOTICE: It is recommended that the heater and
vent system be checked once a year by a qualifi ed
serviceman.
All Maintenance/Ser vice info should be recorded
accordingly on the Inspection Sheet provided in this
manual.
Open all disconnect switches
and disconnect all electrical and gas supplies
and secure in that position before servicing
unit. Failure to do so may result in personal
injury or death from electrical shock.
Gas tightness of the safety shut-
off valves must be checked on at least an annual
basis.
To check gas tightness of the safety shut-off valves, turn off
the manual valve upstream of the appliance combination
control. Remove the 1/8 inch pipe plug on the inlet side
of the combination control and connect a manometer to
that tapping. Turn the manual valve on to apply pressure
to the combination control. Note the pressure reading on
the manometer, then turn the valve off. A loss of pressure
indicates a leak. If a leak is detected, use a soap solution
to check all threaded connections. If no leak is found,
combination control is faulty and must be replaced before
putting appliance back in service.
Should maintenance be required, perform the following
inspection and service routine:
1. Inspect the area near the unit to be sure that
there is no combustible material located within the
minimum clearance requirements listed in this
manual.
Under no circumstances should
combustible material be located within the
clearances specified in this manual. Failure
to provide proper clearance could result in
personal injury or equipment damage from fi re.
2. Turn OFF the manual gas valve and electrical
power to the gas unit heater.
MANIFOLD PRESSURE ADJUSTMENT
If the manifold pressure requires minor adjustment,
remove the cap from the pressure regulator and turn
the adjustment screw clockwise to increase the
pressure, or counterclockwise to decrease the
pressure. The adjusted manifold pressure should not
vary more than 10% from the pressures specified in
Table 4.