14
PV500-56 06/12
12. TROUBLESHOOTING
Condition
Solutions
1. Burner motor runs and:
No flame after pre-purge
Check 24V feed to airflow switch & after airflow switch to control. Fix or
replace the airflow switch. If there is no secondary power, then replace
the 24V transformer.
No flame, faulty ignition transformer or spark
separately
Check ignition transformer output from Honeywell control and check for
cracked electrode or gap. Fix or replace.
Burner locks out after 4 seconds
First, check ionization electrode, ionization cable (for cracks) and boot.
Fix as needed.
Polarity
reversed
Check power feed for reversed polarity following instructions in the
Commissioning Checklist, Section 10.1.
Bad earth grounding
Fix the ground wire.
Gas supply pressure is too low
Check the gas supply regulator and adjust to proper pressure, check that
gas piping is adequately sized following the instructions in Section 6, Gas
Supply and Piping.
2. Pulsation – *
Follow the instructions in Section 10, Burner Setup and Adjustment and using a combustion analyzer,
readjust combustion air as required to obtain proper combustion.
Gas pressure is too high.
Use manometer and readjust the inlet pressure. *
Manifold pressure too high
Use manometer and readjust regulator for correct manifold pressure.*
Burner is dirty
Clean burner.
Venting is inadequate
Adjust barometric damper, clear flue and cap of foreign materials or
correct vent system following the instructions in Section 5, Venting, to
provide draft within the specified range.
Misadjusted burner head
First correct by steps above, if still pulsating, adjust to a lower head
position number. Manifold pressure must be readjusted to match that
shown on the burner information decal and combustion must be
rechecked following the instructions in Section 10, Burner Setup and
Adjustment.
3. Burner
locks
out
Ionization current is too low
Check current. Minimum 0.8 micro amps. Check position of ionization
electrode and the condition of the cable.
4. The CO content is too high
Excess air is too low or possibly too high
Adjust air shutter.
The gas holes in pressure plate are clogged
Clean them.
The fresh air intakes are too small
Increase the size of combustion air openings to those specified in Section
4, Combustion and Ventilation Air.
Negative pressure in mechanical room
Remove source of negative pressure and/or increase size of combustion
air openings.
Gas supply is too high or too low
Check the gas supply regulator adjust to proper pressure, check that gas
piping is adequately sized following the instructions in Section 10, Burner
Setup and Adjustment.
Burner settings or adjustment incorrect
Follow the instructions in Section 10, Burner Setup and Adjustment and
using a combustion analyzer.
5. Condensation in the heat exchanger
Firing Rate is too low
Check burner combustion. If combustion is in range, increase firing rate
so the gross stack temperature is at least 350
o
F (177
o
C) by adjusting to
a higher head position number. Manifold pressure must be readjusted to
match that shown on the burner information decal and combustion must
be rechecked following the instructions in Section 10, Burner Setup and
Adjustment. If allowed by code and vent manufacturer, insulate the vent.
