DT Series - Installation manual (V3_2020)
35
13.4.
TROUBLESHOOTING CHECK LIST
NOTE:
Refer to the normal operating sequence and service check list below to identify
possible causes of problems.
The
Honeywell S7800A
keyboard module displays the following trouble codes which are
the most important regarding the operation of the heater. (Refer to the manufacturer
for any code not listed below).
FIREYE AND HONEYWELL TROUBLESHOOTING CHECK LIST
SYMPTOMS
CORRECTIVE ACTION
✓
The burner is off.
1.
Turn ON main disconnect switch
2.
Check for heat request command
3.
Check line voltage
4.
Check secondary circuit fuse (120 volts)
5.
If ALARM light of the flame safeguard relay (FIREYE or HONEYWELL) flashes, press the reset button
6.
Check adjustment of the overload relay of the fan motor; re-adjust if necessary
7.
Check if flue vent or combustion air intake are blocked or if there is too much restriction in the
ducting
8.
Check if heat exchanger or condensate drain are blocked
9.
Check if pressure switches are defective
10.
Consult factory
✓
Frequency noise
CODE (6) FIREYE
1.
Check for a high voltage source close to the flame safeguard relay
2.
Check electrical wiring between building distribution panel and the heater
3.
Consult factory
✓
Flame failure (PTFI)
CODE (7) FIREYE
CODE (28) HONEYWELL
NOTE: The flame safeguard relay
goes into alarm mode during the
pilot ignition cycle.
1.
Check pilot gas supply
2.
Check pilot ignition transformer
3.
Check flame signal intensity (pilot only: it should range between 5 and 10 VDC for Fireye or
between 3 and 5 VDC for Honeywell)
4.
Check if manual and electric pilot gas supply valves are opened
5.
Check condition of the flame rod ceramic; replace if necessary
6.
Check the flame safeguard amplifier; replace if necessary
7.
Refer to the manufacturer
✓
Flame failure (MTFI)
CODE (19) FIREYE
CODE (17) HONEYWELL
NOTE: The flame safeguard relay
goes into alarm mode during the
pilot ignition cycle.
1.
Check if a gas interruption has occurred during heater operation
2.
With burner in operation, check gas pressure at burner manifold
3.
Check flame signal intensity (pilot only: it should range between 5 and 10 VDC for Fireye or
between 3 and 5 VDC for Honeywell over the entire modulation range)
4.
Perform a combustion test
5.
Consult factory
✓
Flame failure
CODE (19) HONEYWELL
NOTE: The flame safeguard relay
goes into alarm mode during the
burner ignition cycle.
1.
Check burner gas piping and burner electrical connections
2.
Check condition of the flame rod ceramic; replace if necessary
3.
Check flame signal intensity (between 5 and 10 VDC for Fireye or between 3 and 5 VDC for
Honeywell)
4.
Perform a combustion test over the entire capacity range of the burner
✓
Air pressure switch opened
CODE (21) FIREYE
CODE (32) HONEYWELL
NOTE: While the heater is in
operation, safety contact between
6 and 8 terminals for Fireye and 6
and 7 for Honeywell relay must be
There are two safety devices connected in series between terminals 6 and 7 of the
Honeywell
flame
safeguard, and 6 and 8 terminals for the
Fireye
flame safeguard relay.
Burner pressure switch
The burner pressure switch proved that the
burner is in operation. (Adjusted between
0.5''-1
’’
w.c.)
1.
Check burner fan rotation.
2.
Check for obstruction in chimney.
3.
Check for obstruction at combustion air intake.
4.
Check sampling tubes of the pressure switch
(installation and adjustment).
5.
Replace pressure switch if defective.
6.
Consult factory
