Campo Equipment ECOBlaze DF2500 Manual page 12

Testing Air Pressure Differential Switch
The DF2500 uses an air pressure differential
switch to confirm that the main blower is
moving enough air through the heater.
This switch must be activated before the burner
will ignite. The switch senses the difference
between the velocity developed by the blower.
Any restrictions beyond the set point limit
of the switch to the inlet of the heater will
cause the switch to open and shut the
burner off. All discharge duct work must be
removed before testing the switch.
1. Check the sensing tube from the "HIGH"
port on the switch body to the port right
under the switch for kinks or obstructions.
Insure the sensing line is connected to the
switch. The "HIGH" port sensing tube is
located perpendicular and facing into the
air stream.
2. To test if the switch is functioning,
disconnect and insulate wires leading to the
switch N.O. contacts.
ohmmeter or continuity light to the switch
N.O. contacts. Place the Heat/Fan switch to
"FAN" position. The ohmmeter should read
low resistance or the continuity light should
come on. When the blower is stopped the
light should go out and the resistance
reading should be high. If the contacts
remain closed regardless of the blower
status, the air switch must be replaced.
Contact the factory in the event the
switch must be replaced. Only factory
authorized personnel can replace and
calibrate the air switch.
Testing High Limit Switch
The High limit switch is a solid-state device.
When the output contacts are operating
properly, the limit switch will allow the heater to
run when the Heat/Fan switch is placed in the
"Heat" position, as long as the air temperature
at the limit sensor is below the "HIGH LIMIT that
is 150°F". Once the temperature rises above
150°F, limit switch will open and cut the power
to the burner. A manual reset push button
Tel: (905) 793-2525 | Fax: (905) 793-8768 |
pg. 12
Connect an
CAMPO EQUIPMENT CO. LTD. (ECOBLAZE)
6 Carson Court, Brampton, ON, CANADA, L6T 4P8
located on the control panel needs to be
pressed to restore the power to the burner.
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