12
Midco International Inc.
8471 95
Part 1 Installation
WARNING: Ignition is automatic. Con
fi
rm that gas utilization equipment does not
contain any accumulated gases. Purge as described in step 3 below.
CAUTION: Cover plates, guards, and enclosures must be maintained in place at all
times except during maintenance and service.
1. Check the burner piping and valves for gas leaks by applying a weak liquid soap solution to
unions and joints with the gas supply on. Leakage will be indicated by the appearance of soap
bubbles. Locate and correct all gas leaks before proceeding.
WARNING: DO NOT USE OPEN FLAME.
2. Purging the air from the gas supply line at this step will expedite
fi
rst light-o
ff
.
IMPORTANT
: Purge outside the building. Do not purge into the gas utilization equipment.
3. To purge the gas utilization equipment and chimney of any accumulated gases, turn main
Manual Gas Shut-o
ff
Valve to
OFF
, close Pilot Manual Shut-O
ff
Valve, turn burner power
ON
, and
set operating control to
ON
to call for heat. Let the blower run long enough to accomplish four
combustion chamber volume air changes, but for not less than two minutes.
CAUTION: Make sure that the capacity range of the burner is suitable for capacity
rating of the gas utilization equipment. Refer to Speci
fi
cation Section page 2
4.
RESET
the 120 volt
RM7895
fl
ame safeguard by pushing its reset button.
RESET
the
LME71
fl
ame safeguard by holding down the info button for one second. See Section VIII.
5. Con
fi
rm that both the Main and Pilot Manual Shut-O
ff
Valves are open. Turn main Manual Gas
Shut-o
ff
Valve to
ON
.
6. Turn operating control to
ON
. After the prepurge is complete, the pilot should ignite. Whenever
the burner pilot fails to light during the ignition trial, or if the
fl
ame is lost during the burner run
and is not reestablished within 15 seconds after the prepurge, the ignition system will shut o
ff
the Automatic Safety Shut-o
ff
Valves and
LOCK OUT.
For the
120V models RESET
the
fl
ame
safeguard as described above. If burner still fails to light, turn it o
ff
and repeat from step 4 above.
For the
24V models RESET
the 24 volt ignition Control Module by setting the operating control to
OFF for at least 30 seconds. Then if necessary, refer to
Section XII
to isolate the problem.
__________________________________________
1. With the burner o
ff
, install a barb
fi
tting on the
⅛″
NPT pressure tap downstream of the pilot
regulator.
2. Use
fl
exible tubing to hook up a manometer to the barb
fi
tting.
3. Turn the burner to
ON
. After the 30 second pre-purge, the pilot solenoid valve should open.
With the pilot solenoid valve open, adjust the pressure with the pilot regulator based on the type of
pilot that is installed. For internal pilots, set the pressure to 3.0
″
W.C.. For external pilots, set the
pressure to 1.5
″
W.C..
__________________________________________
1. Open Manifold Gas Shut-o
ff
Valve, see Figure 5.
2. Adjust the input signal to 2.0V DC.
3
Use the sight glass on the back plate of the burner to look at the low
fi
re. If light is visible
through all of the holes in the burner plate, the low
fi
re is set within the range of operation of
the burner. If light is not visible through all of the holes, then the low
fi
re is too low and the low
fi
re bypass located on the side of the ratio regulator, see Figure 9 item # 6, needs to be opened
(counter-clockwise to open, clockwise to close).
__________________________________________
VI Initial
Start-up/Adjustment
for 120V and 24V
!
!
A - Initial Light
Up
!
!
i - Reset 120V
ii - Reset 24V
B - Pilot Pressure
Pilot Gas Manifold
Pressure Tap
Pilot Gas
Pressure
Regulator
Supply Gas
Pressure Tap
Main Manual
Gas Shut-off
Valve
Main Gas Pressure
Regulator
Figure 5 -
Pilot Gas Pressure Tap and Regulator
C -
Low Fire
Adjustment