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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Содержание HWC PREMIER 122
Страница 1: ...Service Reference Manual HWC Thru the Wall Units Models HWC Premier 122 182 242 302 123 183 243 303...
Страница 13: ...Service Reference Manual SEQUENCE OF OPERATIONS 2 3 SRM HW HWC 2 99 BLANK PAGE...
Страница 25: ...Service Reference Manual SEQUENCE OF OPERATIONS 2 15 SRM HW HWC 2 99 BLANK PAGE...
Страница 31: ...Service Reference Manual SEQUENCE OF OPERATIONS 2 21 SRM HW HWC 2 99 BLANK PAGE...
Страница 41: ...Service Reference Manual SEQUENCE OF OPERATIONS 2 31 SRM HW HWC 2 99 BLANK PAGE...
Страница 109: ...6 2 INSTALLATION Magic Pak HW HWC SRM HW HWC 8 99 Installation and Operation in Extremely Cold Weather Areas 6 15...
