Unit components magic-pak: hw/hwc – Armstrong World Industries HWC PREMIER 183 User Manual
Page 85
5-22
UNIT COMPONENTS
Magic-Pak: HW/HWC
SRM-HW/HWC 2/99
TABLE 5-4
Pressure Switches
Pressure Switch Problems
The negative pressure developed in the combustion chamber is directly
related to airflow. During furnace operation, the switch will react to
conditions that reduce airflow, such as: blocked or restricted intake
(combustion air piping), blockage of vent (flue) piping, blockage of the
condensate drain piping, plugged pressure tap ports, leaking hoses or a
failure of the induced draft blower motor.
If the pressure switch has already been replaced and problems are still
being experienced, follow the procedure, Checking Pressure Switch
Operation (found on page 5-24).
If the measured static pressure reading does not meet the switch specifi-
cations, check these items:
1.
Pressure switch hose/tubing for cracks or loose connections
2.
Induced draft blower wheel for corrosion or loose blades
3.
Induced draft blower for tight bearings or loose inducer wheel
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