49
Heating Troubleshooting
Use the unit Scrolling Marquee display or a CCN device to view
the heating status display and the heating diagnostic display (see
Appendix A) for information on the heating operation. Check the
current alarms and alarm history for any heating alarm codes and
correct any causes. (See Table 12.) Verify any unique control
configurations per installed site requirements or accessories. If
alarms conditions are corrected and cleared, operation of the heat
stages and indoor fan may be verified by using the Service Test
mode. (See Table 4.)
Gas Heat (48PG Units)
See Table 17 for general gas heating service analysis. See Fig. 23
for service analysis of the IGC board logic. Check the status LED
on the IGC board for any flashing alarm codes and correct any
causes. (See Table 18.)
Electric Heat (50PG Units)
See Table 19 for electric heating service analysis.
Table 17 – Gas Heating Service Analysis
PROBLEM
CAUSE
REMEDY
Heat Will Not Turn On.
Unit is NOT configured for heat.
Check heating configurations using the
Comfort
Link Scrolling
Marquee
Burners Will Not Ignite.
Active alarm.
Check active alarms using
Comfort
Link
™
Scrolling Marquee
and the IGC flash codes.
No power to unit.
Check power supply, fuses, wiring, and circuit breakers.
No power to IGC (Integrated Gas Control).
Check fuses and plugs.
Heaters off due to time guard to prevent short
cycling.
Check using
Comfort
Link Scrolling Marquee and the IGC flash
codes.
Thermostat or occupancy schedule set point not
calling for Cooling.
Check using
Comfort
Link Scrolling Marquee.
No gas at main burners.
Check gas line for air and purge as necessary. After purging gas
line of air, allow gas to dissipate for at least 5 minutes before
attempting to re-light unit.
Water in gas line.
Drain water and install drip.
Inadequate Heating.
Dirty air filters.
Replace air filters.
Gas input too low.
Check gas pressure at manifold. Refer to gas valve adjustment.
Thermostat or occupancy schedule set point only
calling for W1.
Allow time for W2 to energize or adjust setpoints.
Unit undersized for load.
Decrease load or increase of size of unit.
Restricted airflow.
Remove restriction. Check SAT compared to the SAT heating
limits.
Too much outdoor air.
Check economizer position and configuration. Adjust minimum
position using
Comfort
Link Scrolling Marquee
.
Limit switch cycles main burners.
Check rotation of blower, thermostat heat anticipator settings,
and temperature rise of unit. Adjust as needed.
Poor Flame
Characteristics.
Incomplete combustion (lack of combustion air)
results in: Aldehyde odors, CO, sooting flame, or
floating flame.
Check all screws around flue outlets and burner compartment.
Tighten as necessary.
Cracked heat exchanger, replace.
Unit is over-fired, reduce input. Adjust gas line or manifold
pressure.
Check vent for restriction. Clean as necessary.
Check orifice to burner alignment.
Burners Will Not Turn Off.
Unit is in Minimum on-time.
Check using
Comfort
Link Scrolling Marquee and the IGC flash
codes.
Unit running in Service Test mode.
Check using
Comfort
Link Scrolling Marquee.
Main gas valve stuck.
Turn off gas supply and unit power. Replace gas valve.
48/
50P
G
and
P
M
Содержание 48/50PG Series
Страница 32: ...32 C07009 Fig 20 Air Baffle Dimensions 48 50PG03 16 48 50PG and PM...
Страница 33: ...33 C08077 Fig 21 Air Baffle Dimensions 48 50PG20 28 and 48 50PM16 28 48 50PG and PM...
Страница 58: ...58 C08549 Fig 28 48PG03 16 Control Wiring Schematic 48 50PG and PM...
Страница 59: ...59 C08550 Fig 29 50PG03 16 Control Wiring Schematic 48 50PG and PM...
Страница 60: ...60 C08551 Fig 30 Typical 48 50PG03 16 Power Wiring Schematic and Legend 48 50PG16 460 3 60 Shown 48 50PG and PM...
Страница 64: ...64 C08471 Fig 34 Typical 48PG and PM16 28 Control Schematic 48PM16 28 Shown 48 50PG and PM...
Страница 66: ...66 C08557 Fig 36 Typical 50PG and PM16 28 Control Schematic 50PG20 28 Shown 48 50PG and PM...
Страница 67: ...67 C08064 Fig 37 Typical 50PG and PM16 28 with Humidi MiZert Control Schematic 50PM16 28 Shown 48 50PG and PM...
Страница 68: ...68 C08558 Fig 38 Typical 48 50PG and PM16 28 Power Schematic 48 50PM16 28 Shown 48 50PG and PM...
Страница 72: ...72 C08565 Fig 42 Typical 48 50PG20 28 Component Arrangement 48 50PG20 24 Shown 48 50PG and PM...
Страница 73: ...73 C08067 Fig 43 48 50PM16 28 Component Arrangement 48 50PG and PM...
Страница 74: ...74 C08562 Fig 44 48 50PM16 28 with Humidi MiZert Component Arrangement 48 50PG and PM...
Страница 208: ...208 48 50PG and PM...
