Effective: January 2020
F-35-53-CE
5
CONTROL WIRE HARNESS
Select the proper harness based on the 35-53CE control's ter
-
mination connection. Standard wire lengths are 12, 18, 24 30,
36 and 48 inches. Refer to Fenwal Controls datasheet F-05-
1000 for details.
High Voltage and Remote Sense Cable
Requirements
The HV Ignition Cable must meet a voltage rating of 25 KV and
an insulation rating of 200 °C. Suppression type UL 3257 or SAE
J2031 ratings are recommended. Recommend length of 3ft
(.9m) or less. Consult factory for longer lengths.
Remote flame sense cable must meet a voltage rating of 250V
and an insulation rating of 200 °C. Recommended length of 10ft
(3m) or less. Consult Factory for longer lengths.
Refer to Fenwal Controls datasheet F-05-1000 for details.
SPARK ELECTRODES/FLAME SENSORS
Critical for gas-fired appliances, proper design, construction,
and application assures reliable ignition and optimal perfor
-
mance. Fenwal Controls uses only glazed Alumina ceramics and
certified rod materials suitable up to 2175°F (1190°C). Spark
electrodes typically have a 0.125” gap between the high voltage
(HV) rod tip and the ground rod or burner. Flame sensors are a
single rod used in flame rectification circuit of the ignition con
-
trol to confirm the presence (or absence) of the flame.
Refer to Fenwal Controls datasheet F-22-100 for details.
Proper Electrode Location
Proper location of electrode assembly is important for optimum
system performance. The electrode assembly should be located
so that the tips are inside the flame envelope and about 1/2-inch
(1.2 cm) above the base of the flame as shown:
Notes:
•
Ceramic insulators must not be in or close to the flame.
•
Electrode assemblies must not be adjusted or
disassembled. Electrodes are NOT field adjustable.
•
Electrodes should have a gap spacing of 0.125 in (3.12
mm), unless otherwise specified by the appliance
manufacturer. Larger gaps may not perform as
intended in all conditions. If spacing is not correct, the
assembly must be replaced.
•
Exceeding temperature limits can cause nuisance
lockouts and premature electrode failure.
•
Electrodes must be located where they are not exposed
during normal operation.
Flame Current Measurement
Flame current is the current which passes through the flame
from the sensor to ground to complete the primary safety cir
-
cuit. The minimum flame current necessary to keep the system
from lockout is 0.7µA. To measure flame current:
1.
Disconnect Input Voltage.
2.
Insert a 0-50µA DC meter and capacitor in series with the
sensor electrode and wire as shown below.
The meter should read 0.7µA or higher while flame is estab
-
lished. If the meter reads below “0” on the scale, the meter
leads are reversed. Disconnect power and reconnect meter
leads for proper polarity.
CAUTION
When monitoring flame current, use a 1.0µF,
250 VDC bypass capacitor to protect the meter
from damage.
Control
Unit
µA Meter
Spark
Output
1µF
