Adp SEP-100, Installation Instructions Manual, Page: 14 / 20

To Turn Off Gas to Unit
1 − Set thermostat to lowest level.
2 − Turn off all electrical power to unit if service is to
be performed.
3 − Turn knob on gas valve 90° clockwise to OFF.
Heating Sequence of Operation
1 − When the thermostat calls for heat, the
combustion air inducer starts immediately.
2 − Combustion air pressure switch proves inducer
operation before allowing power to the ignition
controller. This switch is factory-set and no
adjustment is necessary.
3 − After prepurge of approximately 30 seconds, the
spark ignition is energized and the solenoid valves
open in the gas valve. SEP models 230, 250, 300,
345 and 400 are equipped with a step opening
valve. During ignition phase of start-up, a
pressure of approximately 25% of full rate allows
even ignition of all burners for several seconds
before full rate pressure is established.
4 − The spark then ignites the gas, the ignition sensor
proves the flame, and the combustion process
continues.
5 − in the event that the flame is not detected after
the first 10 −second trial for ignition, the controller
will repeat steps 3 and 4 an additional two times
before locking out the gas valve. Ignition control
will then automatically repeat steps 3, 4, and 5
after 60 minutes.
NOTE: To interrupt the 60
−minute lockout period, move
thermostat from Heat" to OFF" then back to Heat."
Heating sequence then restarts at step 1.
6 − The burners must light without noticeable crossover
delay. There must be no flame lifting from the burner
heads, flashback or burning within the burner. The
flames should be predominantly blue in color and
should be approximately centered in the tubes with
no apparent impingement taking place.
7 − The ignition control will energize the fan(s)
approximately 45 seconds after ignition is
established.
8 − After the thermostat demand is satisfied, the gas
valve is closed. Five seconds after the demand is
satisfied, the combustion air inducer is shut off.
9 − The ignition control must shut off the system fan
approximately 150 seconds after the gas valve is
de-energized.
Ignition Control LED
The ignition control contains a green LED which
indicates the following:
TABLE 8
IGNITION CONTROL LED
LED UNIT OPERATION
Slow
Normal Operation − No call for heat
Flash*
Fast
Normal Operation − Call for heat
Flash
2 System lockout − failed to detect or sustain
Flashes flame
3 Pressure switch failed closed before CAI is en-
Flashes ergized or failed open after CAI is energized
4
High limit or rollout switch open
Flashes
5
Flame sensed and gas valve not energized
Flashes
Steady
Loss of power
Off
Steady
Ignition control failure
On
*When thermostat is placed in continuous fan mode, LED will
slowly flash.
High Altitude Adjustment
In Canada, certification for installation at altitudes over
4500 feet (1372m) above sea level is the jurisdiction of
the local authorities.
Unit may be fired at full input up to 2000 feet (610m)
above sea level. Above 2000 feet (610m), manifold
pressure must be adjusted on some units. Adjust
pressure regulator to pressure shown in table 9 for
natural gas and table 10 for LP/propane gas.
In some cases, it is necessary to change the pressure
switch to ensure proper operation at higher altitudes.
See table 1.
NOTE
− A natural to LP/propane gas changeover kit is
required to convert the unit in the field. Refer to the
installation instructions supplied with the changeover kit
for conversion procedure.
If unit is installed at an altitude greater than 7500 feet
(2286m), unit must be derated by four percent for each
additional 1000 feet (305m) above 7500 feet (2286m).
The combustion air inducer proving switch is factory set
and no adjustment is necessary.
14