Dettson Chinook C105-M-V, Installation Instructions And Homeowner'S Manual

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welded closed or purposely bypassed in the field. Before
any heat cycle can begin, the pressure switch is tested to
make sure that it is opened. The switch is ignored except
in gas heating modes.
12.16.2 Causes
1. Faulty switch.
2. Pressure switch physically bypassed in the field.
3. Loose or faulty wiring.
4. Abnormally high negative pressure present on vent
system without inducer running.
12.16.3 Solutions
1. Replace low pressure control switch.
2. Remove bypass and restore correct operation. De-
termine reason for bypass (e.g. vent length too
long) and correct issue. Notify homeowner and
proper authorities of illegal tampering if necessary.
3. Check wiring and connections. Replace and/or re-
pair as necessary.
4. Check for proper venting and terminations as de-
fined in the furnace installation instruction.
12.17 45 - Low Pressure Control
Switch Open
12.17.1 Description
This fault indicates that the low pressure switch is open
when the inducer is energized at high speed. Since the
furnace only ignites at high fire, this condition should
never be seen except after the blower on delay period
of the ignition cycle oand only after the furnace attempt
to switch to a firing rate below 50%.
12.17.2 Causes
1. Blockage or improper termination in either the inlet
or exhaust vents.
2. The flue vent length and/or number of elbows ex-
ceeds the maximum number specified.
3. Faulty or disconnect inducer
4. Loose or faulty wiring
5. Disconnect, blocked or cut pressure switches
hoses
6. Wind gusts (sporadic)
7. Faulty pressure switch
12.17.3 Solutions
1. Check the vent system for blockage and proper ter-
mination and repair as necessary
2. Remove excess venting
3. Check inducer, wiring and electrical connections
4. Replace control board
5. Check wiring and connections
6. Check and replace hose
7. Insure proper termination
8. Change pressure switch
12.18 46 - Low Pressure Control
Switch Open
12.18.1 Description
This fault indicates that the low pressure switch is open
when the inducer is energized at low speed. The switch
must close after the inducer is energized and before the
ignition sequence can begin.
12.18.2 Causes
1. Blockage or improper termination in either the inlet
of exhaust vents.
2. The flue vent length and/or number of elbows ex-
ceeds the maximum number specified.
3. Faulty or disconnect inducer
4. Loose or faulty wiring
5. Disconnect, blocked, spit or cut pressure switches
hoses
6. Wind gusts (sporadic)
7. Faulty pressure switch
12.18.3 Solutions
1. Check the vent system for blockage and proper ter-
mination and repair as necessary
2. Remove excess venting
3. Check inducer, wiring and electrical connections
4. Replace control board
5. Check wiring and connections
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