ICM Controls ICM2811 Installation, Operation & Application Manual page 2

Inducer Pre Purge
Igniter Warm Up
Trial for Ignition
Retries
Inducer Post Purge
Inducer Interpurge
Heat Blower ON Delay
Heat Blower OFF Delay
Cool Blower ON Delay
Cool Blower OFF Delay
Ignition Lock Out Reset
Self Healing Recovery
Flame Sense Troubleshooting Tips
Flame not established
1. If the flame is not established and proved during the 4
second initial sequence, there will be two more successive
attempts allowed each having a 30 second inducer purge
between attempts.
2. After three successive attempts, if flame is still not proven
there will be a 1 hour and 15 minutes lock out before the
system will try for ignition again.
Flame out
1. Flame out is considered when flame is lost during heating.
2. When a W signal is present and flame is not sensed, the
gas valve will disengage until the next trial for ignition. The
circulating blower and inducer will remain running.
3. If flame is not established in the 4 second initial trial, the
control will continue with 2 additional trials for ignition
4. After three successive attempts, if flame is still not proven,
there will be a 1 Hour 15 min lock out before the system
will try for ignition again.
Flame out of sequence
1. Flame out of sequence represents a scenario when flame
is sensed while W signal is not present.
2. Inducer and Blower motors will be engaged (if not already
running) and keep running for as long as the fault condition
is present.
Timing
15 seconds
9 seconds
4 seconds
2
15 seconds
30 seconds
30 seconds
90/120/150/180 seconds
5 seconds
45 seconds
75 minutes
3 minutes
Lockout Features
There is a 3 minute self-healing delay which occurs following
a rollout or high limit switch recovery. Once the rollout and
high limit switch have closed (recovered) and the delay has
expired, the thermostat call will be enforced. However, if the
high limit or rollout switch remain open; the fault condition
and lockout will remain in place until the high limit and rollout
safeties are restored.
If the pressure switch opens during pre- purge and remains
open beyond the 15 second window, the control extends
the inducer pre-purge time up to 5 minutes if necessary.
However, if the pressure switch closes before the 5 minute
extended pre-purge, the control will clear the fault and
resume normal operation. If the pressure switch remains
open for longer than 5 minutes, the control will enter a 75
minute system lockout. There will also be a 75 minute system
lock out if the flame is not established and proved within 3
successive attempts.
Heating Blower Delay Options
To select different heat blower OFF delay options, move the
jumper on J1 to the desired setting according to the Jumper
position table below.
J1 Jumper Position
1 & 2
2 & 3
3 & 4
4 & 5
Twinning
The ICM2811 is twinning compatible with another ICM2811
control board only. To enable twinning, connect the "TWIN"
terminals together and ground the common of both 24 VAC
transformers to earth ground. The controls are designed to
turn on/off the blower simultaneously and at the same speed.
(NOTE: An external AC relay, whose coil is connected
between R & W of the primary furnace and whose normally
open contacts connect R & W of the secondary furnace,
must be provided to cause both furnaces to heat). A common
ground between the two furnaces is also required.
Time
180 seconds
150 seconds
120 seconds
90 seconds