TROUBLESHOOTING GUIDE
LED Indication
Steady on
1 Flash
2 Flashes
3 Flashes
Fault Mode
Internal Control Failure
Airflow Fault
Flame Fault
**
Ignition Lockout Fault
MOUNTING AND WIRING
The 35-71 is not position sensitive and can be mounted vertically or
horizontally. The control may be mounted on any surface and fastened
with #6 sheet metal screws. Secure the control in an area that will
experience a minimum of vibration and remain below the maximum
ambient temperature of 80°C (175°F).
All connections should be made with UL approved, 105°C rated, 18 gauge,
stranded, .054” thick insulated wire. Refer to the appropriate wiring
diagram when connecting the 35-71 to other components in the system. High
voltage spark cables and control wiring harnesses are detailed on
Pages 5 and 6.
Series 35-71, 120 VAC Direct Spark Ignition Control
Page 3
1/4”
3/16”
1/4”
3/16”
3/16”
1/4”
1/4”
1/4”
3/16”
1/4”
Alarm
Valve Power
Pressure Switch
120 VAC Neutral
Valve Neutral
120 VAC Input (Hot)
Inducer Output
Thermostat Input
Burner Ground
Remote Flame Sensor
Flame Sense Test Pins
NC
V1
PSW
L2
V2
L1
IND
TH
B.GND
S1
*
FC+, FC-
11
10
9
8
7
6
4
3
2
1
Blue
Brown
Orange
White
Yellow
Black
White/Black
Red
Purple
Gray
TERMINAL
DESCRIPTION
MULTI-PIN
CONNECTOR
P/N: AMP 1-644615-1
QUICK
CONNECT
TERMINAL
SIZE
Terminal Designations
PIN
LOCATION
WIRE
COLOR
2 Pin Header
(AMP P/N: 640383-2, Molex P/N: 26-60-2020)
CAUTION:
Label all wires prior to disconnection when servicing the
control. Wiring errors can cause improper and dangerous operation.
A functional checkout of a replacement is necessary to prevent porperty
damage and/or personal injury or death.
*
On controls configured for single spark and sense with quick connects,the S1
terminal is removed. On controls configured for single spark and sense with
multi-pin connector, leave S1 wire, pin 1, color gray unconnected.
I
nput Power
Input Current Drain
Gas Valve Rating
Combustion Blower Rating
Operating Temperature
Flame Sense Voltage
Flame Sense Current
Flame Failure Response Time
Type of Gas
Spark Rate
Moisture Resistance
Size (LxWxH)
Weight
102 to 138 VAC, 50/60 Hz
350mA @ 120 VAC, 60 Hz
1.5A @ 120 VAC
3.0 FLA @ 120 VAC
-40°F to +175°F, -40°C to +80°C
120 VAC
1.0 microamp minimum
0.8 seconds maximum
Natural, LP and manufactured
Line frequency (50/60 Hz)
Conformal coated to operate to 95% R.H.
See drawings on Page 8
Integral stand-offs: 7.1 oz
Potted: 14.3 oz Case and Cover: 10.1
oz
SPECIFICATIONS
The LED will flash on for 0.2 seconds then off for 0.2 seconds to indicate an
error condition. The pause time between error codes will be 2.5 to 3.0 seconds.
During power-up, the LED will light for one second and then turn off to indicate
normal operation
.
ON-BOARD DIAGNOSTICS
**
May indicate either that a flame was detected during pre-, inter- or post-purge,
or that there is a flame sensing error.
WARNING:
Operation outside specifications could result in failure of
Fenwal product and other equipment with injury to people and damage
to property and even death.
PIN LAYOUT
FULL TIME POWER
NO FULL TIME POWER
Single
Spark
and
Sense
Remote
Sense
On controls without full time
power the TH terminal is not
used and L1 becomes the
T’stat or control device input.
www.fenwalcontrols.com
1-800-FENWAL-1
Symptom
Control will not start up
Gas Valve on and
no spark during TFI
Spark on and gas valve
off
Flame during TFI but no
flame sense after TFI
Call for ignition, but
combustion blower
doesn't start up
Pressure switch operating
properly, but no TFI after
purge period
Recommended Actions
A. Check for 120VAC at L1 and/ or TH
B. Check fuse/ circuit breaker
C. Check thermostat on and set above ambient
D. Red LED steady on. Reset power. Replace
control if LED remains on.
A. Shorted electrode - re-establish 1/8" gap
B. Check that bracket is making a solid
ground connection
C. Check connection at each end of high
voltage cable
A. Check for 120VAC at V1
B. Check wiring to V1 and V2
C. Valve coil malfunction
A. Check that the spark electrode/ flame
sensor are in the flame
B. Poor ground at the burner
C. Low flame current - check flame current
using test pins on the control
A. Check for 120VAC at L1 and TH
B. Check for 120VAC at IND, should be on if
pressure switch is operating properly
C. Check that the pressure switch has been
wired properly
D. Pressure switch failed off or on (1 LED Flash)
E. Check blower fan assembly
A. Flame was detected during purge period
(2 LED Flashes)
B. Check for 120VAC at L1 and TH
C. Check for 120VAC at IND, should be on
if pressure switch is operating properly
