22
HE+ Series Modulating Supplemental Manual
Flame Fault
If at any time the main valve fails to close completely and maintains a flame, the full time flame
sense circuit will detect it and energize the combustion blower. Should the main valve later close
completely removing the flame signal, the combustion blower will power off following the optional
post purge period.
MOUNTING AND WIRING
The Fenwal DSI Control 24 VAC Tube Heater (905000020) is not position sensitive and can be
mounted vertically or horizontally. The case may be mounted on any surface with #6 sheet metal
screws. All wiring must be done in accordance with local and national electrical code. Refer to wire
diagram page 35 when connecting 905000020 to other components in the burner.
The Fenwal DSI Control 24 VAC Tube Heater
(905000020) uses voltages of shock hazard po-
tential. Wiring and initial operation must be done
by a qualified service technician. The control
must be secured in an area that will experience
a minimum of vibration and remain below the
operating temperature of 160ºF. All connec-
tions should be made with UL approved 105ºC
rated 18 gauge, stranded, .054 thick insulated
wire. Refer to wire diagram page 35 when con-
necting the Series 35
-
61 to other components in
the burner.
CAUTION:
Label all wires prior to disconnection when servicing controls. Wiring errors can cause improper
and dangerous operation. A functional checkout of a replacement control is recommended.
PROPER ELECTRODE LOCATION
Proper location of the electrode assembly is important
for optimum system performance. The electrode assem-
bly should be located so that the spark gap is inside the
flame envelope about 1 inch (2.5 cm) from the base of
the flame at the burner cup.
Electrodes should have a gap spacing of
3/16” (0.188”
±
0.031”
or 4.76 mm ± 0.81 mm). If this
spacing is not correct, the assembly must be adjusted or replaced. DO NOT adjust the curved ig-
niter/sensor prong. Adjust/bend only the ground prong (also see next page).
WARNING
TERMI-
NAL
DESIGNATION
SPADE
TH
Thermostat Input
1/4”
PSW
Pressure Switch Input
1/4”
V1
Valve Power (MV)
1/8”
IND
Inducer Blower Output
1/4”
NC
Alarm (Not used)
-
L1
120/240 VAC Input (Hot)
1/4”
24 VAC
24 VAC Supply to Processor
1/4”
V2
Valve (MV)
1/8”
GND
Valve & System Ground
1/8”
Spark
Spark & Local Flame Sense
1/4”
