Aqua-Hot Hydronic Heating System Shop Manual 09/04
®
SECTION 8: DIESEL-BURNER SERVICE, MAINTENANCE, AND REPAIR INFORMATION
Flame
Sensor
8.4
Flame Sensor
Function:
The
Flame Sensor
is a photoresistive device, which supplies the
Diesel-Burner’s
Controller
with a DC voltage signal when it detects a flame (i.e., a light
source).
NOTE:
The functionality of each component can be determined by completing
the manual checks, as listed under the “Component Test” area for each
individual component, or the components can be tested by using a
“Controller Tester.” Reference Section 11 for Special Tools information
NOTES:
A:
In order to perform the following procedures, it is necessary to detach
and reattach the
Diesel-Burner Head
. Therefore, be sure to review
Section 8.2 for detaching and reattaching instructions.
B:
Be sure to calibrate your ohmmeter prior to checking the
Flame Sensor
for proper resistance values.
Component Test:
Locate and detach the Flame Sensor’s
Green
and
Blue
wires from
the C-Plug Harness
wires
; reference Figure 15. Connect the Flame Sensor's
Green
and
Blue
wires to an ohmmeter; reference Figure 15. Check resistance by placing a shop rag
over the Flame Sensor's glass surface to simulate a no-flame condition, then, remove the
rag (and expose to a light source) to simulate a flame condition. If the
Flame Sensor
is
operating properly, the ohmmeter should register high resistance (i.e., 100K Ω +) when
the glass surface is covered and less than 300 Ω when exposed to a light source. If
these resistance numbers cannot be obtained, the
Flame Sensor
must be replaced;
reference the Flame Sensor's “Replacement Procedure” in this section. Reference
Section 10 for spare parts information.
Cleaning Tips/Maintenance:
For light dirt, dust, and/or carbon deposits, simply wipe off
the
Flame Sensor
with a soft cloth. Should heavy carbon deposits exist, completely
remove the
Flame Sensor
form the
Photo Disc
and clean with brake cleaner; reference
Figure 15.
Adjustment Procedure:
N/A
Replacement Procedure:
1.
Remove the
Screw
, which fastens the
Flame Sensor
to the
Photo Disc
and detach the sensor’s
Green
and
Blue
wires from the C-Plug Harness’
Green
and
Violet
wires; reference Figure 15.
2.
Slide the tab of the new
Flame Sensor
into the provided slot in the
Photo
Disc
and secure in place with the screw; reference Figure 15. Connect
the Flame Sensor’s
Green
wire to the
Green
C-Plug Harness wire and
the
Blue
wire to the C-Plug Harness’
Violet
wire; reference Figure 15.
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